Merge pull request 'Sprint 0 / #20: хранилище состояния — SQLite WAL, миграции, audit log, атомарный apply/rollback' (#50) from feat/20-storage into main

Sprint 0 / #20: хранилище состояния — SQLite WAL, миграции, audit log, атомарный apply/rollback

Правки по ревью QA (#54 critical, #55 D-1/D-2) внесены и приняты:
RLock на чтения, BaseException → revert + failed в аудите, old_value внутри транзакции.
Гейт на merge-состоянии (main + PR): ruff/format чисто, mypy strict 21 файл,
pytest 107 passed / coverage 97.80% (порог 70%), 55/55 AC-проб, 28/28 security-проб,
мутационная проверка тестов пройдена. Ревью: qa-engineer (APPROVE) + TechLead.
Refs #20, #54, #55, #52.

backend/awg_api/store/README.md

@@ -0,0 +1,66 @@
+# store — хранилище состояния (issue #20)
+
+SQLite (WAL) в `/data/awg-dash.db`: правила маршрутизации, исключения, режим,
+расписание GeoIP, метаданные конфигов, устройства, журнал аудита и снимки
+состояния. Путь переопределяется аргументом или переменной `AWG_DASH_DB`.
+
+| Модуль | Назначение |
+|---|---|
+| `db.py` | открытие соединения, PRAGMA (WAL, `synchronous=NORMAL`, `foreign_keys`, `busy_timeout`), транзакции `BEGIN IMMEDIATE` |
+| `migrations.py` | версионированные миграции, `schema_migrations`, проверка схемы при старте (`verify_schema`) |
+| `models.py` | dataclass-модели сущностей и перечисления (`Mode`, `Entity`, `Rule`, …) |
+| `validation.py` | чистые функции валидации (domain/CIDR/ipset, MAC, cron, режим, политика) |
+| `repository.py` | `Store`: чтения + аудируемые мутации «кто/когда/что/old→new» |
+| `audit.py` | запись и чтение `audit_log` (мутация и её аудит — одна транзакция) |
+| `state.py` | снимки состояния (`state_snapshots`), `capture_state`, `restore_state`, `rollback_to_snapshot` |
+| `apply.py` | `ApplyEngine`: `validate → stage → apply → rollback` и протокол `Applier` (awg/iptables) |
+| `service.py` | `open_storage()` — сборка `Database + Store + ApplyEngine` для старта приложения |
+| `errors.py` | `StorageError`, `SchemaError`, `ValidationError`, `ApplyError(restored=…)` |
+
+## Гарантии
+
+- **Пустой `/data`** — каталог создаётся, миграции применяются, схема v1 появляется без ручных действий.
+- **Версия схемы** — при старте схема проверяется: новее ожидаемой или не мигрированная → `SchemaError` (без «автоотката»).
+- **Аудит** — каждая мутация пишет `actor/ts/action/entity/old_value/new_value` в `audit_log` в той же транзакции; `old_value` читается внутри той же транзакции, поэтому конкурентные обновления не рвут цепочку `old→new`.
+- **Атомарность** — применяемое состояние проходит `validate → stage → apply`; падение внешнего применителя откатывает транзакцию БД и вызывает `Applier.revert(previous)`, `ApplyError.restored=True`. Ловится `BaseException`, поэтому отмена (`asyncio.CancelledError`), `KeyboardInterrupt` и `SystemExit` тоже дают `revert` и запись `failed` в журнале.
+- **Откат** — `ApplyEngine.rollback(plan_id)` возвращает состояние из снимка.
+
+## Потокобезопасность (#54)
+
+Контракт: **одно соединение на процесс, все операции под одним `RLock`**.
+
+| Операция | API | Поведение |
+|---|---|---|
+| Мутация | `Database.transaction()` | `BEGIN IMMEDIATE` … `COMMIT`/`ROLLBACK` под локом |
+| Чтение | `Database.read()` | берёт тот же лок; ждёт завершения чужой транзакции |
+| Прямой доступ | `Database.connection` / `Store.raw()` | лок **не** берётся — только однопоточный код (миграции, тесты, отладка) |
+
+Следствия, на которые можно опираться в API-слое (#19/#21):
+
+- обычные чтения (`GET /rules`, `GET /mode`, …) не падают от конкурентных мутаций и не отдают перемешанный результат операторов;
+- читатель **не видит** незафиксированных строк другой транзакции;
+- во время `apply` наружу не видно состояние, которое затем будет откачено (AC «не частично применённая конфигурация»);
+- конкурентные запросы ждут, а не получают ошибку; потокобезопасность подтверждена `backend/tests/test_store_concurrency.py`.
+
+WAL остаётся включённым: он даёт устойчивость к падению процесса и позволяет читать БД снаружи (`sqlite3` CLI) во время работы шлюза. Внутрипроцессного параллелизма чтений контракт не обещает: если позже понадобится параллельная пропускная способность, меняем контракт на «соединение на поток» (`threading.local`), а не полагаемся на неявное поведение.
+
+## Пример
+
+```python
+from awg_api.store import DesiredState, Rule, open_storage
+
+with open_storage() as storage:  # /data/awg-dash.db
+    storage.store.set_geoip_schedule(cron="0 3 * * *", actor="ui:admin")
+    plan = storage.engine.stage(
+        DesiredState(
+            mode=storage.store.get_mode(), rules=(Rule("yt", "domain", "youtube.com", "tun0"),)
+        ),
+        reason="ui: split-tunnel для YouTube",
+    )
+    result = storage.engine.apply(plan)
+```
+
+## Тесты
+
+`backend/tests/test_store_*.py` — миграции, аудит, репозиторий, apply/rollback,
+персистентность после рестарта. Порог покрытия — 70 % (`pyproject.toml`).

backend/awg_api/store/__init__.py

@@ -0,0 +1,103 @@
+"""Слой хранения состояния awg-dash (issue #20).
+
+Состав: SQLite (WAL) в ``/data/awg-dash.db``, версионированные миграции,
+проверка схемы при старте, журнал аудита «кто/когда/что/old→new» и движок
+атомарного применения ``validate -> stage -> apply -> rollback``.
+"""
+
+from __future__ import annotations
+
+from .apply import (
+    Applier,
+    ApplyEngine,
+    ApplyResult,
+    DesiredState,
+    NullApplier,
+    StagedPlan,
+)
+from .audit import count as audit_count
+from .audit import last_entry as audit_last_entry
+from .audit import list_entries as list_audit_entries
+from .audit import record as record_audit
+from .db import DB_PATH_ENV, DEFAULT_DB_PATH, Database, resolve_db_path
+from .errors import ApplyError, SchemaError, StorageError, ValidationError
+from .migrations import (
+    EXPECTED_TABLES,
+    LATEST_VERSION,
+    MIGRATIONS,
+    SCHEMA_MIGRATIONS,
+    Migration,
+    MigrationReport,
+    current_version,
+    migrate,
+    verify_schema,
+)
+from .models import (
+    AUDIT_STATUS_FAILED,
+    AUDIT_STATUS_OK,
+    AUDIT_STATUS_STAGED,
+    DEVICE_POLICIES,
+    RULE_KINDS,
+    AuditEntry,
+    ConfigMeta,
+    Device,
+    Entity,
+    GeoIpSchedule,
+    Mode,
+    Rule,
+    RuleException,
+)
+from .repository import Store
+from .service import Storage, open_storage, rollback_to
+from .state import StateSnapshot, capture_state, restore_state, rollback_to_snapshot
+
+__all__ = [
+    "AUDIT_STATUS_FAILED",
+    "AUDIT_STATUS_OK",
+    "AUDIT_STATUS_STAGED",
+    "DB_PATH_ENV",
+    "DEFAULT_DB_PATH",
+    "DEVICE_POLICIES",
+    "EXPECTED_TABLES",
+    "LATEST_VERSION",
+    "MIGRATIONS",
+    "RULE_KINDS",
+    "SCHEMA_MIGRATIONS",
+    "Applier",
+    "ApplyEngine",
+    "ApplyError",
+    "ApplyResult",
+    "AuditEntry",
+    "ConfigMeta",
+    "Database",
+    "DesiredState",
+    "Device",
+    "Entity",
+    "GeoIpSchedule",
+    "Migration",
+    "MigrationReport",
+    "Mode",
+    "NullApplier",
+    "Rule",
+    "RuleException",
+    "SchemaError",
+    "StagedPlan",
+    "StateSnapshot",
+    "Storage",
+    "StorageError",
+    "Store",
+    "ValidationError",
+    "audit_count",
+    "audit_last_entry",
+    "capture_state",
+    "current_version",
+    "list_audit_entries",
+    "migrate",
+    "open_storage",
+    "record_audit",
+    "resolve_db_path",
+    "restore_state",
+    "rollback_to",
+    "rollback_to_snapshot",
+    "verify_schema",
+]

backend/awg_api/store/apply.py

@@ -0,0 +1,325 @@
+"""Атомарное применение состояния: ``validate -> stage -> apply -> rollback`` (issue #20).
+
+Гарантии:
+
+* **validate** — несостоятельное желаемое состояние не доходит до БД;
+* **stage** — перед мутацией сохраняется снимок текущего состояния (durable,
+  в отдельной таблице ``state_snapshots``), поэтому откат возможен в любой момент;
+* **apply** — мутация БД и запись в ``audit_log`` выполняются в одной транзакции,
+  внешнее применение (iptables/awg) вызывается внутри неё: падение внешнего
+  применителя откатывает транзакцию, то есть БД возвращается к предыдущему
+  состоянию целиком, без частичных изменений;
+* **rollback** — явный возврат к снимку по id.
+
+Ошибка применения поднимает :class:`ApplyError` (поле ``restored=True``): API
+должен ответить ошибкой, не «полуприменённой» конфигурацией. Ловится
+``BaseException`` (#55 D-1), поэтому отмена запроса тоже вызывает
+``Applier.revert(previous)`` и закрывает запись аудита исходом ``failed`` —
+«висящих» записей ``staged`` без исхода не остаётся.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Mapping
+from dataclasses import dataclass, field
+from typing import Any, Protocol, runtime_checkable
+
+from . import audit, state, validation
+from .errors import ApplyError, ValidationError
+from .models import (
+    AUDIT_STATUS_FAILED,
+    AUDIT_STATUS_OK,
+    AUDIT_STATUS_STAGED,
+    Entity,
+    GeoIpSchedule,
+    Mode,
+    Rule,
+    RuleException,
+)
+from .repository import Store
+from .state import StateSnapshot
+
+
+@dataclass(frozen=True, slots=True)
+class DesiredState:
+    """Полное желаемое состояние шлюза (то, что применяется как единое целое)."""
+
+    mode: Mode
+    rules: tuple[Rule, ...] = ()
+    geoip: GeoIpSchedule = field(default_factory=GeoIpSchedule)
+    exceptions: tuple[RuleException, ...] = ()
+
+    def to_payload(self) -> dict[str, Any]:
+        return {
+            "mode": self.mode.value,
+            "geoip": self.geoip.as_dict(),
+            "rules": [
+                {
+                    "name": rule.name,
+                    "kind": rule.kind,
+                    "match": rule.match,
+                    "target": rule.target,
+                    "priority": rule.priority,
+                    "enabled": rule.enabled,
+                }
+                for rule in self.rules
+            ],
+            "exceptions": [
+                {
+                    "match": exception.match,
+                    "reason": exception.reason,
+                    "enabled": exception.enabled,
+                }
+                for exception in self.exceptions
+            ],
+        }
+
+    @classmethod
+    def from_payload(cls, payload: Mapping[str, Any]) -> DesiredState:
+        """Разобрать желаемое состояние из JSON-совместимого словаря."""
+        raw_rules = payload.get("rules", [])
+        if not isinstance(raw_rules, (list, tuple)):
+            raise ValidationError("rules", "ожидается список правил")
+        rules = tuple(_rule_from_mapping(item) for item in raw_rules)
+        raw_exceptions = payload.get("exceptions", [])
+        if not isinstance(raw_exceptions, (list, tuple)):
+            raise ValidationError("exceptions", "ожидается список исключений")
+        exceptions = tuple(_exception_from_mapping(item) for item in raw_exceptions)
+        geoip_raw = payload.get("geoip") or {}
+        if not isinstance(geoip_raw, Mapping):
+            raise ValidationError("geoip", "ожидается объект расписания")
+        geoip = GeoIpSchedule(
+            enabled=bool(geoip_raw.get("enabled", True)),
+            cron=str(geoip_raw.get("cron", "0 4 * * *")),
+            provider=str(geoip_raw.get("provider", "ripe")),
+        )
+        return cls(
+            mode=validation.validate_mode(str(payload.get("mode", Mode.OFF.value))),
+            rules=rules,
+            geoip=geoip,
+            exceptions=exceptions,
+        )
+
+
+def _rule_from_mapping(item: Any) -> Rule:
+    if not isinstance(item, Mapping):
+        raise ValidationError("rules", f"ожидается объект правила, получено {item!r}")
+    try:
+        return Rule(
+            name=str(item["name"]),
+            kind=str(item["kind"]),
+            match=str(item["match"]),
+            target=str(item["target"]),
+            priority=int(item.get("priority", 100)),
+            enabled=bool(item.get("enabled", True)),
+        )
+    except KeyError as exc:
+        raise ValidationError("rules", f"в правиле нет обязательного поля {exc.args[0]!r}") from exc
+
+
+def _exception_from_mapping(item: Any) -> RuleException:
+    if not isinstance(item, Mapping):
+        raise ValidationError("exceptions", f"ожидается объект исключения, получено {item!r}")
+    try:
+        return RuleException(
+            match=str(item["match"]),
+            reason=str(item.get("reason", "")),
+            enabled=bool(item.get("enabled", True)),
+        )
+    except KeyError as exc:
+        raise ValidationError(
+            "exceptions", f"в исключении нет обязательного поля {exc.args[0]!r}"
+        ) from exc
+
+
+@runtime_checkable
+class Applier(Protocol):
+    """Внешний применитель состояния (awg/iptables/ipset)."""
+
+    def apply(self, payload: Mapping[str, Any]) -> None:
+        """Применить состояние во внешней подсистеме. Падение -> ApplyError."""
+
+    def revert(self, payload: Mapping[str, Any]) -> None:
+        """Вернуть внешнюю подсистему к состоянию ``payload`` при откате."""
+
+
+@dataclass(frozen=True, slots=True)
+class StagedPlan:
+    """Промежуточный план: снимок предыдущего состояния + желаемое состояние."""
+
+    plan_id: int
+    desired: DesiredState
+    previous: dict[str, Any]
+    actor: str
+    reason: str
+
+
+@dataclass(frozen=True, slots=True)
+class ApplyResult:
+    """Успешный результат применения."""
+
+    ok: bool
+    plan_id: int
+    audit_id: int
+    message: str
+
+
+class NullApplier:
+    """Заглушка внешнего применителя (для тестов и dry-run режима)."""
+
+    def apply(self, payload: Mapping[str, Any]) -> None:
+        return None
+
+    def revert(self, payload: Mapping[str, Any]) -> None:
+        return None
+
+
+class ApplyEngine:
+    """Оркестратор ``validate -> stage -> apply -> rollback``."""
+
+    def __init__(
+        self, store: Store, applier: Applier | None = None, *, actor: str = "system"
+    ) -> None:
+        self._store = store
+        self._applier: Applier = applier if applier is not None else NullApplier()
+        self._actor = actor
+
+    # -- стадии ---------------------------------------------------------
+    def validate(self, desired: DesiredState) -> DesiredState:
+        """Проверить желаемое состояние, не касаясь БД."""
+        validation.validate_mode(desired.mode)
+        validation.validate_cron(desired.geoip.cron)
+        validation.validate_provider(desired.geoip.provider)
+        seen: set[str] = set()
+        for rule in desired.rules:
+            validation.validate_name("name", rule.name)
+            kind = validation.validate_rule_kind(rule.kind)
+            validation.validate_match(kind, rule.match)
+            validation.validate_target(rule.target)
+            validation.validate_priority(rule.priority)
+            if rule.name in seen:
+                raise ValidationError("rules", f"дублирующееся имя правила: {rule.name!r}")
+            seen.add(rule.name)
+        for exception in desired.exceptions:
+            validation.validate_exception_match(exception.match)
+        return desired
+
+    def stage(self, desired: DesiredState, *, reason: str = "") -> StagedPlan:
+        """Проверить состояние и сохранить снимок предыдущего состояния."""
+        self.validate(desired)
+        payload = desired.to_payload()
+        with self._store.database.transaction() as conn:
+            previous = state.capture_state(conn)
+            plan_id = state.save_snapshot(conn, previous, reason=reason or "pre-apply")
+            audit.record(
+                conn,
+                actor=self._actor,
+                action="stage",
+                entity=Entity.APPLY.value,
+                entity_id=plan_id,
+                old_value=previous,
+                new_value=payload,
+                status=AUDIT_STATUS_STAGED,
+                detail=reason,
+            )
+        return StagedPlan(
+            plan_id=plan_id, desired=desired, previous=previous, actor=self._actor, reason=reason
+        )
+
+    def apply(self, plan: StagedPlan) -> ApplyResult:
+        """Применить план. При падении — откатить БД и внешнюю подсистему.
+
+        :raises ApplyError: если применитель упал; ``restored=True`` означает,
+            что предыдущее состояние подтверждённо восстановлено.
+
+        Ловится ``BaseException``, не только ``Exception`` (#55 D-1): отмена
+        запроса (``asyncio.CancelledError``), ``KeyboardInterrupt`` и
+        ``SystemExit`` тоже обязаны вернуть внешнюю подсистему в предыдущее
+        состояние и закрыть запись аудита исходом ``failed``. Иначе iptables
+        останется в новом состоянии, тогда как ``audit_log`` сохранит
+        «висящую» запись ``staged`` без исхода. Исключения из ``Exception``
+        преобразуются в :class:`ApplyError`, остальные пробрасываются как есть
+        (семантика отмены сохраняется).
+        """
+        payload = plan.desired.to_payload()
+        audit_id: int
+        try:
+            with self._store.database.transaction() as conn:
+                state.restore_state(conn, payload)
+                self._applier.apply(payload)
+                audit_id = audit.record(
+                    conn,
+                    actor=plan.actor,
+                    action="apply",
+                    entity=Entity.APPLY.value,
+                    entity_id=plan.plan_id,
+                    old_value=plan.previous,
+                    new_value=payload,
+                    status=AUDIT_STATUS_OK,
+                    detail=plan.reason,
+                )
+        except BaseException as exc:
+            restored_ok = self._rollback_failed_apply(plan, exc)
+            if not isinstance(exc, Exception):
+                raise
+            raise ApplyError(
+                f"применение состояния не удалось: {exc}",
+                restored=restored_ok,
+                audit_id=self._last_failed_audit_id(plan),
+            ) from exc
+        return ApplyResult(
+            ok=True, plan_id=plan.plan_id, audit_id=audit_id, message="состояние применено"
+        )
+
+    def apply_payload(self, payload: Mapping[str, Any], *, reason: str = "") -> ApplyResult:
+        """validate + stage + apply одной командой (для сервисного слоя)."""
+        desired = self.validate(DesiredState.from_payload(payload))
+        return self.apply(self.stage(desired, reason=reason))
+
+    def rollback(self, plan_id: int, *, reason: str = "") -> StateSnapshot:
+        """Явно вернуть состояние к снимку плана."""
+        with self._store.database.transaction() as conn:
+            return state.rollback_to_snapshot(conn, plan_id, actor=self._actor, reason=reason)
+
+    # -- внутреннее -----------------------------------------------------
+    def _rollback_failed_apply(self, plan: StagedPlan, exc: BaseException) -> bool:
+        """Вернуть внешнюю подсистему и убедиться, что БД = предыдущее состояние.
+
+        Откат внешней подсистемы — best-effort: падение ``revert`` не мешает
+        восстановить БД и записать исход в журнал (причина падения revert
+        попадает в ``detail``), и наоборот — падение revert не должно скрывать
+        исходное исключение.
+        """
+        revert_error: BaseException | None = None
+        try:
+            self._applier.revert(plan.previous)
+        except BaseException as revert_exc:  # откат best-effort: исход важнее падения revert
+            revert_error = revert_exc
+        detail = f"{type(exc).__name__}: {exc}"
+        if revert_error is not None:
+            detail += f"; revert: {type(revert_error).__name__}: {revert_error}"
+        with self._store.database.transaction() as conn:
+            state.restore_state(conn, plan.previous)
+            audit.record(
+                conn,
+                actor=plan.actor,
+                action="apply",
+                entity=Entity.APPLY.value,
+                entity_id=plan.plan_id,
+                old_value=plan.desired.to_payload(),
+                new_value=plan.previous,
+                status=AUDIT_STATUS_FAILED,
+                detail=detail,
+            )
+        with self._store.database.read() as conn:
+            return state.capture_state(conn) == plan.previous
+
+    def _last_failed_audit_id(self, plan: StagedPlan) -> int | None:
+        with self._store.database.read() as conn:
+            entries = audit.list_entries(
+                conn, entity=Entity.APPLY.value, entity_id=plan.plan_id, limit=1
+            )
+        if not entries:
+            return None
+        last = entries[0]
+        return last.id if last.status == AUDIT_STATUS_FAILED else None

backend/awg_api/store/audit.py

@@ -0,0 +1,125 @@
+"""Журнал аудита «кто/когда/что/old->new» (issue #20).
+
+Запись всегда выполняется на переданном соединении, то есть внутри уже
+открытой транзакции вызывающего кода: мутация и её аудит коммитятся вместе и
+не могут разойтись.
+"""
+
+from __future__ import annotations
+
+import json
+import sqlite3
+from collections.abc import Mapping
+from typing import Any
+
+from .clock import utcnow
+from .models import AUDIT_STATUS_OK, AuditEntry
+
+__all__ = ["list_entries", "record"]
+
+
+def _dumps(value: Any) -> str | None:
+    if value is None:
+        return None
+    if isinstance(value, Mapping):
+        return json.dumps(dict(value), sort_keys=True, ensure_ascii=False, default=str)
+    return json.dumps(value, sort_keys=True, ensure_ascii=False, default=str)
+
+
+def _loads(value: Any) -> Any:
+    if value is None:
+        return None
+    if isinstance(value, (bytes, bytearray)):
+        value = value.decode("utf-8")
+    return json.loads(str(value))
+
+
+def record(
+    conn: sqlite3.Connection,
+    *,
+    actor: str,
+    action: str,
+    entity: str,
+    entity_id: str | int | None = None,
+    old_value: Any = None,
+    new_value: Any = None,
+    status: str = AUDIT_STATUS_OK,
+    detail: str | None = None,
+    ts: str | None = None,
+) -> int:
+    """Записать событие в ``audit_log`` и вернуть id записи."""
+    if not actor:
+        raise ValueError("actor обязателен: аудит должен знать, кто изменил состояние")
+    cursor = conn.execute(
+        """
+        INSERT INTO audit_log (ts, actor, action, entity, entity_id,
+                               old_value, new_value, status, detail)
+        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
+        """,
+        (
+            ts or utcnow(),
+            actor,
+            action,
+            entity,
+            None if entity_id is None else str(entity_id),
+            _dumps(old_value),
+            _dumps(new_value),
+            status,
+            detail,
+        ),
+    )
+    return int(cursor.lastrowid or 0)
+
+
+def list_entries(
+    conn: sqlite3.Connection,
+    *,
+    entity: str | None = None,
+    entity_id: str | int | None = None,
+    limit: int = 100,
+) -> list[AuditEntry]:
+    """Прочитать журнал аудита (свежие первыми)."""
+    sql = "SELECT * FROM audit_log"
+    clauses: list[str] = []
+    params: list[Any] = []
+    if entity is not None:
+        clauses.append("entity = ?")
+        params.append(entity)
+    if entity_id is not None:
+        clauses.append("entity_id = ?")
+        params.append(str(entity_id))
+    if clauses:
+        sql += " WHERE " + " AND ".join(clauses)
+    sql += " ORDER BY id DESC LIMIT ?"
+    params.append(int(limit))
+    rows = conn.execute(sql, params).fetchall()
+    return [
+        AuditEntry(
+            id=int(row["id"]),
+            ts=str(row["ts"]),
+            actor=str(row["actor"]),
+            action=str(row["action"]),
+            entity=str(row["entity"]),
+            entity_id=None if row["entity_id"] is None else str(row["entity_id"]),
+            old_value=_loads(row["old_value"]),
+            new_value=_loads(row["new_value"]),
+            status=str(row["status"]),
+            detail=None if row["detail"] is None else str(row["detail"]),
+        )
+        for row in rows
+    ]
+
+
+def count(conn: sqlite3.Connection, *, entity: str | None = None) -> int:
+    """Сколько записей в журнале (опционально — по сущности)."""
+    if entity is None:
+        row = conn.execute("SELECT COUNT(*) FROM audit_log").fetchone()
+    else:
+        row = conn.execute("SELECT COUNT(*) FROM audit_log WHERE entity = ?", (entity,)).fetchone()
+    return int(row[0]) if row is not None else 0
+
+
+def last_entry(conn: sqlite3.Connection, *, entity: str | None = None) -> AuditEntry | None:
+    """Последняя запись журнала (опционально — по сущности)."""
+    entries = list_entries(conn, entity=entity, limit=1)
+    return entries[0] if entries else None

backend/awg_api/store/clock.py

@@ -0,0 +1,16 @@
+"""Источник времени для audit_log и снимков состояния.
+
+Отдельный модуль — чтобы тесты могли подменять время детерминированно
+(``monkeypatch.setattr(clock, "utcnow", ...)``).
+"""
+
+from __future__ import annotations
+
+from datetime import UTC, datetime
+
+__all__ = ["utcnow"]
+
+
+def utcnow() -> str:
+    """Текущее время в UTC: ISO-8601, миллисекунды, суффикс ``Z``."""
+    return datetime.now(UTC).isoformat(timespec="milliseconds").replace("+00:00", "Z")

backend/awg_api/store/db.py

@@ -0,0 +1,175 @@
+"""Открытие и жизненный цикл SQLite-хранилища состояния (issue #20, ADR-006).
+
+Путь по умолчанию — ``/data/awg-dash.db`` (персистентный volume контейнера),
+переопределяется аргументом или переменной окружения ``AWG_DASH_DB``.
+Каталог создаётся автоматически, поэтому на пустом ``/data`` схема v1
+поднимается без ручных действий.
+
+Соединение открывается в режиме WAL: ``synchronous=NORMAL`` достаточен для WAL
+(риск потери только последних транзакций при падении операционной системы, БД
+при этом не разрушается).
+
+Контракт потокобезопасности (#54): соединение одно на процесс, все операции —
+и записи (:meth:`Database.transaction`), и чтения (:meth:`Database.read`) —
+выполняются под одним ``RLock``. Поэтому:
+
+* результаты операторов из разных потоков не перемешиваются (нет
+  ``TypeError``/``IndexError``);
+* читатель не видит незафиксированных строк чужой транзакции и состояния,
+  которое затем будет откачено (падение внешнего применителя);
+* конкурентные запросы ждут, не падают.
+
+WAL при этом остаётся: он даёт устойчивость к падению процесса и позволяет
+читать БД снаружи (``sqlite3`` CLI) во время работы шлюза. Если позже
+понадобится параллельная пропускная способность чтений, контракт меняется на
+«соединение на поток» (``threading.local``) — это отдельное решение, не
+молчаливое поведение.
+"""
+
+from __future__ import annotations
+
+import os
+import sqlite3
+import threading
+from collections.abc import Iterator
+from contextlib import contextmanager
+from pathlib import Path
+
+from .errors import StorageError
+from .migrations import MigrationReport, current_version, migrate, verify_schema
+
+DEFAULT_DB_PATH = "/data/awg-dash.db"
+DB_PATH_ENV = "AWG_DASH_DB"
+BUSY_TIMEOUT_MS = 5000
+
+_WAL_PRAGMAS: tuple[str, ...] = (
+    "PRAGMA journal_mode = WAL",
+    "PRAGMA synchronous = NORMAL",
+    "PRAGMA foreign_keys = ON",
+    "PRAGMA busy_timeout = 5000",
+)
+
+
+def resolve_db_path(path: str | os.PathLike[str] | None = None) -> Path:
+    """Определить путь к БД: аргумент -> ``AWG_DASH_DB`` -> ``/data/awg-dash.db``."""
+    if path is None:
+        path = os.environ.get(DB_PATH_ENV) or DEFAULT_DB_PATH
+    return Path(path)
+
+
+class Database:
+    """Соединение SQLite: миграции, проверка схемы, транзакции."""
+
+    def __init__(
+        self,
+        path: str | os.PathLike[str] | None = None,
+        *,
+        auto_migrate: bool = True,
+    ) -> None:
+        self.path = resolve_db_path(path)
+        self._lock = threading.RLock()
+        self._conn = self._open(self.path)
+        self.migration_report: MigrationReport | None = None
+        if auto_migrate:
+            self.migrate()
+        else:
+            verify_schema(self._conn)
+
+    # -- соединение -----------------------------------------------------
+    @staticmethod
+    def _open(path: Path) -> sqlite3.Connection:
+        if str(path) != ":memory:":
+            try:
+                path.parent.mkdir(parents=True, exist_ok=True)
+            except OSError as exc:
+                raise StorageError(f"не удалось создать каталог {path.parent}: {exc}") from exc
+        try:
+            conn = sqlite3.connect(
+                str(path),
+                isolation_level=None,
+                check_same_thread=False,
+                timeout=BUSY_TIMEOUT_MS / 1000,
+            )
+            conn.row_factory = sqlite3.Row
+            for pragma in _WAL_PRAGMAS:
+                conn.execute(pragma)
+        except sqlite3.Error as exc:
+            raise StorageError(f"не удалось открыть БД {path}: {exc}") from exc
+        return conn
+
+    @property
+    def connection(self) -> sqlite3.Connection:
+        """Прямой доступ к соединению — только для однопоточного кода.
+
+        Рантайм API/сервисного слоя использует :meth:`read` (чтения) и
+        :meth:`transaction` (мутации): они берут общий лок и гарантируют
+        согласованность результата (#54).
+        """
+        return self._conn
+
+    @property
+    def journal_mode(self) -> str:
+        with self._lock:
+            row = self._conn.execute("PRAGMA journal_mode").fetchone()
+        return str(row[0]) if row is not None else ""
+
+    @property
+    def is_wal(self) -> bool:
+        return self.journal_mode.lower() == "wal"
+
+    @property
+    def schema_version(self) -> int:
+        with self._lock:
+            return current_version(self._conn)
+
+    # -- схема ----------------------------------------------------------
+    def migrate(self) -> MigrationReport:
+        """Применить неприменённые миграции и проверить схему."""
+        with self._lock:
+            report = migrate(self._conn)
+        self.migration_report = report
+        return report
+
+    def verify_schema(self) -> None:
+        """Проверить соответствие фактической схемы ожидаемой версии."""
+        with self._lock:
+            verify_schema(self._conn)
+
+    # -- транзакции и чтения --------------------------------------------
+    @contextmanager
+    def transaction(self) -> Iterator[sqlite3.Connection]:
+        """Транзакция ALL-OR-NOTHING (``BEGIN IMMEDIATE`` + rollback при ошибке)."""
+        with self._lock:
+            self._conn.execute("BEGIN IMMEDIATE")
+            try:
+                yield self._conn
+            except BaseException:
+                self._conn.rollback()
+                raise
+            else:
+                self._conn.commit()
+
+    @contextmanager
+    def read(self) -> Iterator[sqlite3.Connection]:
+        """Согласованное чтение под общим локом (#54).
+
+        Ждёт завершения чужой транзакции и потому не видит незафиксированных
+        строк и состояния, которое затем будет откачено. Внутри уже открытой
+        транзакции того же потока лок реентерабелен, поэтому читать можно и из
+        неё.
+        """
+        with self._lock:
+            yield self._conn
+
+    def close(self) -> None:
+        with self._lock:
+            try:
+                self._conn.close()
+            except sqlite3.Error as exc:  # pragma: no cover - защита от гонок при shutdown
+                raise StorageError(f"ошибка закрытия БД: {exc}") from exc
+
+    def __enter__(self) -> Database:
+        return self
+
+    def __exit__(self, *exc_info: object) -> None:
+        self.close()

backend/awg_api/store/errors.py

@@ -0,0 +1,33 @@
+"""Иерархия ошибок хранилища awg-dash."""
+
+from __future__ import annotations
+
+
+class StorageError(RuntimeError):
+    """Базовая ошибка слоя хранения состояния."""
+
+
+class SchemaError(StorageError):
+    """Схема БД не соответствует ожидаемой версии (или требует отката)."""
+
+
+class ValidationError(StorageError):
+    """Данные не прошли валидацию до применения (стадия validate)."""
+
+    def __init__(self, field: str, message: str) -> None:
+        super().__init__(f"{field}: {message}")
+        self.field = field
+        self.message = message
+
+
+class ApplyError(StorageError):
+    """Ошибка применения конфигурации.
+
+    ``restored`` — предыдущее состояние подтверждённо восстановлено,
+    ``audit_id`` — id записи в audit_log, статус ``failed``.
+    """
+
+    def __init__(self, message: str, *, restored: bool, audit_id: int | None) -> None:
+        super().__init__(message)
+        self.restored = restored
+        self.audit_id = audit_id

backend/awg_api/store/migrations.py

@@ -0,0 +1,299 @@
+"""Версионированные миграции схемы состояния (issue #20).
+
+Схема БД управляется списком :class:`Migration`. Каждая миграция выполняется
+в своей транзакции, запись версии в ``schema_migrations`` — там же: падение
+миграции не оставляет «полуприменённой» схемы.
+
+При старте приложения вызывается :func:`migrate` (создание/обновление схемы)
+и :func:`verify_schema` (проверка, что фактическая схема соответствует
+ожидаемой версии).
+"""
+
+from __future__ import annotations
+
+import sqlite3
+from dataclasses import dataclass
+
+from .clock import utcnow
+from .errors import SchemaError, StorageError
+
+SCHEMA_MIGRATIONS = "schema_migrations"
+
+
+@dataclass(frozen=True, slots=True)
+class Migration:
+    """Одна версия схемы: имя и список DDL-выражений."""
+
+    version: int
+    name: str
+    statements: tuple[str, ...]
+
+
+@dataclass(frozen=True, slots=True)
+class MigrationReport:
+    """Результат :func:`migrate`."""
+
+    from_version: int
+    to_version: int
+    applied: tuple[int, ...]
+
+    @property
+    def changed(self) -> bool:
+        return bool(self.applied)
+
+
+_V1_STATEMENTS: tuple[str, ...] = (
+    f"""
+    CREATE TABLE IF NOT EXISTS {SCHEMA_MIGRATIONS} (
+        version    INTEGER PRIMARY KEY,
+        name       TEXT NOT NULL,
+        applied_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS routing_rules (
+        id         INTEGER PRIMARY KEY AUTOINCREMENT,
+        name       TEXT NOT NULL UNIQUE,
+        kind       TEXT NOT NULL CHECK (kind IN ('domain', 'cidr', 'ipset')),
+        match      TEXT NOT NULL,
+        target     TEXT NOT NULL,
+        priority   INTEGER NOT NULL DEFAULT 100,
+        enabled    INTEGER NOT NULL DEFAULT 1 CHECK (enabled IN (0, 1)),
+        created_at TEXT NOT NULL,
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS rule_exceptions (
+        id         INTEGER PRIMARY KEY AUTOINCREMENT,
+        match      TEXT NOT NULL UNIQUE,
+        reason     TEXT NOT NULL DEFAULT '',
+        enabled    INTEGER NOT NULL DEFAULT 1 CHECK (enabled IN (0, 1)),
+        created_at TEXT NOT NULL,
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS routing_mode (
+        id         INTEGER PRIMARY KEY CHECK (id = 1),
+        mode       TEXT NOT NULL CHECK (mode IN ('off', 'split', 'full')),
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS geoip_schedule (
+        id         INTEGER PRIMARY KEY CHECK (id = 1),
+        enabled    INTEGER NOT NULL DEFAULT 1 CHECK (enabled IN (0, 1)),
+        cron       TEXT NOT NULL,
+        provider   TEXT NOT NULL,
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS configs (
+        id         INTEGER PRIMARY KEY AUTOINCREMENT,
+        name       TEXT NOT NULL UNIQUE,
+        version    INTEGER NOT NULL DEFAULT 1,
+        path       TEXT NOT NULL,
+        checksum   TEXT NOT NULL DEFAULT '',
+        size_bytes INTEGER NOT NULL DEFAULT 0,
+        applied    INTEGER NOT NULL DEFAULT 0 CHECK (applied IN (0, 1)),
+        created_at TEXT NOT NULL,
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS devices (
+        id         INTEGER PRIMARY KEY AUTOINCREMENT,
+        mac        TEXT NOT NULL UNIQUE,
+        name       TEXT NOT NULL,
+        address    TEXT NOT NULL DEFAULT '',
+        policy     TEXT NOT NULL DEFAULT 'default',
+        last_seen  TEXT,
+        created_at TEXT NOT NULL,
+        updated_at TEXT NOT NULL
+    )
+    """,
+    """
+    CREATE TABLE IF NOT EXISTS audit_log (
+        id        INTEGER PRIMARY KEY AUTOINCREMENT,
+        ts        TEXT NOT NULL,
+        actor     TEXT NOT NULL,
+        action    TEXT NOT NULL,
+        entity    TEXT NOT NULL,
+        entity_id TEXT,
+        old_value TEXT,
+        new_value TEXT,
+        status    TEXT NOT NULL DEFAULT 'ok',
+        detail    TEXT
+    )
+    """,
+    "CREATE INDEX IF NOT EXISTS idx_audit_log_entity ON audit_log (entity, entity_id)",
+    "CREATE INDEX IF NOT EXISTS idx_audit_log_ts ON audit_log (ts DESC)",
+    """
+    CREATE TABLE IF NOT EXISTS state_snapshots (
+        id         INTEGER PRIMARY KEY AUTOINCREMENT,
+        entity     TEXT NOT NULL,
+        entity_id  TEXT NOT NULL,
+        created_at TEXT NOT NULL,
+        payload    TEXT NOT NULL,
+        reason     TEXT NOT NULL DEFAULT ''
+    )
+    """,
+    "CREATE INDEX IF NOT EXISTS idx_state_snapshots_key ON state_snapshots (entity, entity_id, id)",
+)
+
+V1_SEED_STATEMENTS: tuple[str, ...] = (
+    "INSERT OR IGNORE INTO routing_mode (id, mode, updated_at) VALUES (1, 'off',"
+    " strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))",
+    "INSERT OR IGNORE INTO geoip_schedule (id, enabled, cron, provider, updated_at) VALUES"
+    " (1, 1, '0 4 * * *', 'ripe', strftime('%Y-%m-%dT%H:%M:%fZ', 'now'))",
+)
+
+MIGRATIONS: tuple[Migration, ...] = (
+    Migration(
+        version=1,
+        name="initial-state-schema",
+        statements=(*_V1_STATEMENTS, *V1_SEED_STATEMENTS),
+    ),
+)
+
+LATEST_VERSION: int = max(migration.version for migration in MIGRATIONS)
+
+#: Ожидаемые таблицы схемы v1 и обязательные колонки каждой из них.
+EXPECTED_TABLES: dict[str, frozenset[str]] = {
+    SCHEMA_MIGRATIONS: frozenset({"version", "name", "applied_at"}),
+    "routing_rules": frozenset(
+        {"id", "name", "kind", "match", "target", "priority", "enabled", "created_at", "updated_at"}
+    ),
+    "rule_exceptions": frozenset({"id", "match", "reason", "enabled", "created_at", "updated_at"}),
+    "routing_mode": frozenset({"id", "mode", "updated_at"}),
+    "geoip_schedule": frozenset({"id", "enabled", "cron", "provider", "updated_at"}),
+    "configs": frozenset(
+        {
+            "id",
+            "name",
+            "version",
+            "path",
+            "checksum",
+            "size_bytes",
+            "applied",
+            "created_at",
+            "updated_at",
+        }
+    ),
+    "devices": frozenset(
+        {"id", "mac", "name", "address", "policy", "last_seen", "created_at", "updated_at"}
+    ),
+    "audit_log": frozenset(
+        {
+            "id",
+            "ts",
+            "actor",
+            "action",
+            "entity",
+            "entity_id",
+            "old_value",
+            "new_value",
+            "status",
+            "detail",
+        }
+    ),
+    "state_snapshots": frozenset({"id", "entity", "entity_id", "created_at", "payload", "reason"}),
+}
+
+
+def table_names(conn: sqlite3.Connection) -> set[str]:
+    """Имена таблиц, фактически присутствующих в БД."""
+    rows = conn.execute("SELECT name FROM sqlite_master WHERE type = 'table'").fetchall()
+    return {str(row[0]) for row in rows}
+
+
+def table_columns(conn: sqlite3.Connection, table: str) -> set[str]:
+    """Колонки таблицы (через параметризованное table-valued PRAGMA)."""
+    rows = conn.execute("SELECT name FROM pragma_table_info(?)", (table,)).fetchall()
+    return {str(row[0]) for row in rows}
+
+
+def current_version(conn: sqlite3.Connection) -> int:
+    """Текущая версия схемы; ``0`` — если таблицы версий ещё нет."""
+    if SCHEMA_MIGRATIONS not in table_names(conn):
+        return 0
+    row = conn.execute(f"SELECT MAX(version) FROM {SCHEMA_MIGRATIONS}").fetchone()  # noqa: S608
+    if row is None or row[0] is None:
+        return 0
+    return int(row[0])
+
+
+def applied_migrations(conn: sqlite3.Connection) -> dict[int, str]:
+    """Карта «версия -> имя» для применённых миграций."""
+    if SCHEMA_MIGRATIONS not in table_names(conn):
+        return {}
+    rows = conn.execute(f"SELECT version, name FROM {SCHEMA_MIGRATIONS}").fetchall()  # noqa: S608
+    return {int(row[0]): str(row[1]) for row in rows}
+
+
+def apply_migration(conn: sqlite3.Connection, migration: Migration) -> None:
+    """Применить одну миграцию в отдельной транзакции (all-or-nothing)."""
+    conn.execute("BEGIN IMMEDIATE")
+    try:
+        for statement in migration.statements:
+            conn.execute(statement)
+        conn.execute(
+            f"INSERT INTO {SCHEMA_MIGRATIONS} (version, name, applied_at) VALUES (?, ?, ?)",  # noqa: S608
+            (migration.version, migration.name, utcnow()),
+        )
+    except sqlite3.Error as exc:  # pragma: no cover - защита от порчи БД
+        conn.rollback()
+        raise StorageError(
+            f"миграция v{migration.version} ({migration.name}) не применена: {exc}"
+        ) from exc
+    except Exception:
+        conn.rollback()
+        raise
+    conn.commit()
+
+
+def migrate(
+    conn: sqlite3.Connection, *, migrations: tuple[Migration, ...] = MIGRATIONS
+) -> MigrationReport:
+    """Применить все неприменённые миграции по возрастанию версии."""
+    start = current_version(conn)
+    known = sorted(migrations, key=lambda migration: migration.version)
+    latest = max((migration.version for migration in known), default=0)
+    if start > latest:
+        raise SchemaError(
+            f"схема БД новее, чем известно приложению: v{start} > v{latest};"
+            " требуется обновление образа, не автооткат"
+        )
+    applied: list[int] = []
+    for migration in known:
+        if migration.version <= start:
+            continue
+        apply_migration(conn, migration)
+        applied.append(migration.version)
+    verify_schema(conn)
+    return MigrationReport(
+        from_version=start, to_version=current_version(conn), applied=tuple(applied)
+    )
+
+
+def verify_schema(conn: sqlite3.Connection) -> None:
+    """Проверить, что фактическая схема соответствует ожидаемой версии.
+
+    Вызывает :class:`SchemaError`, если версия схемы новее ожидаемой или если
+    отсутствует таблица/колонка, на которую рассчитывает приложение.
+    """
+    version = current_version(conn)
+    if version > LATEST_VERSION:
+        raise SchemaError(f"схема БД v{version} новее ожидаемой v{LATEST_VERSION}")
+    if version < LATEST_VERSION:
+        raise SchemaError(f"схема БД v{version} не мигрирована до v{LATEST_VERSION}")
+    existing = table_names(conn)
+    missing_tables = sorted(set(EXPECTED_TABLES) - existing)
+    if missing_tables:
+        raise SchemaError(f"в схеме отсутствуют таблицы: {', '.join(missing_tables)}")
+    for table, required in EXPECTED_TABLES.items():
+        missing_columns = sorted(required - table_columns(conn, table))
+        if missing_columns:
+            raise SchemaError(f"таблица {table}: отсутствуют колонки {', '.join(missing_columns)}")

backend/awg_api/store/models.py

@@ -0,0 +1,186 @@
+"""Модель данных хранилища awg-dash (issue #20).
+
+Каждая сущность описана неизменяемым dataclass-ом; идентификатор ``None``
+означает «ещё не сохранено». Строки времени — UTC ISO-8601, суффикс ``Z``.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+from enum import StrEnum
+from typing import Any
+
+RULE_KINDS: tuple[str, ...] = ("domain", "cidr", "ipset")
+
+DEVICE_POLICIES: tuple[str, ...] = ("default", "tunnel", "direct", "block")
+
+AUDIT_STATUS_OK = "ok"
+AUDIT_STATUS_FAILED = "failed"
+AUDIT_STATUS_STAGED = "staged"
+
+
+class Mode(StrEnum):
+    """Режим маршрутизации шлюза."""
+
+    OFF = "off"
+    SPLIT = "split"
+    FULL = "full"
+
+    @classmethod
+    def values(cls) -> tuple[str, ...]:
+        return tuple(member.value for member in cls)
+
+
+class Entity(StrEnum):
+    """Имена сущностей для audit_log и снимков состояния."""
+
+    RULE = "rule"
+    EXCEPTION = "exception"
+    MODE = "mode"
+    GEOIP_SCHEDULE = "geoip_schedule"
+    CONFIG = "config"
+    DEVICE = "device"
+    APPLY = "apply"
+
+
+@dataclass(frozen=True, slots=True)
+class Rule:
+    """Правило маршрутизации (domain / cidr / ipset -> target)."""
+
+    name: str
+    kind: str
+    match: str
+    target: str
+    priority: int = 100
+    enabled: bool = True
+    id: int | None = None
+    created_at: str | None = None
+    updated_at: str | None = None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "id": self.id,
+            "name": self.name,
+            "kind": self.kind,
+            "match": self.match,
+            "target": self.target,
+            "priority": self.priority,
+            "enabled": self.enabled,
+        }
+
+
+@dataclass(frozen=True, slots=True)
+class RuleException:
+    """Исключение из правил (host/domain, который никогда не маршрутизируется в туннель)."""
+
+    match: str
+    reason: str = ""
+    enabled: bool = True
+    id: int | None = None
+    created_at: str | None = None
+    updated_at: str | None = None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "id": self.id,
+            "match": self.match,
+            "reason": self.reason,
+            "enabled": self.enabled,
+        }
+
+
+@dataclass(frozen=True, slots=True)
+class GeoIpSchedule:
+    """Расписание обновления GeoIP-наборов."""
+
+    enabled: bool = True
+    cron: str = "0 4 * * *"
+    provider: str = "ripe"
+    updated_at: str | None = None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "enabled": self.enabled,
+            "cron": self.cron,
+            "provider": self.provider,
+        }
+
+
+@dataclass(frozen=True, slots=True)
+class ConfigMeta:
+    """Метаданные сгенерированного конфига (сам файл живёт в /config)."""
+
+    name: str
+    path: str
+    version: int = 1
+    checksum: str = ""
+    size_bytes: int = 0
+    applied: bool = False
+    id: int | None = None
+    created_at: str | None = None
+    updated_at: str | None = None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "id": self.id,
+            "name": self.name,
+            "path": self.path,
+            "version": self.version,
+            "checksum": self.checksum,
+            "size_bytes": self.size_bytes,
+            "applied": self.applied,
+        }
+
+
+@dataclass(frozen=True, slots=True)
+class Device:
+    """Известный клиент шлюза."""
+
+    mac: str
+    name: str
+    address: str = ""
+    policy: str = "default"
+    last_seen: str | None = None
+    id: int | None = None
+    created_at: str | None = None
+    updated_at: str | None = None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "id": self.id,
+            "mac": self.mac,
+            "name": self.name,
+            "address": self.address,
+            "policy": self.policy,
+            "last_seen": self.last_seen,
+        }
+
+
+@dataclass(frozen=True, slots=True)
+class AuditEntry:
+    """Запись журнала «кто/когда/что/old->new»."""
+
+    id: int
+    ts: str
+    actor: str
+    action: str
+    entity: str
+    entity_id: str | None
+    old_value: Any
+    new_value: Any
+    status: str
+    detail: str | None
+
+    def as_dict(self) -> dict[str, Any]:
+        return {
+            "id": self.id,
+            "ts": self.ts,
+            "actor": self.actor,
+            "action": self.action,
+            "entity": self.entity,
+            "entity_id": self.entity_id,
+            "old_value": self.old_value,
+            "new_value": self.new_value,
+            "status": self.status,
+            "detail": self.detail,
+        }

backend/awg_api/store/repository.py

@@ -0,0 +1,599 @@
+"""Репозиторий сущностей состояния (issue #20).
+
+Каждая мутация выполняется в одной транзакции, запись в ``audit_log``
+(«кто/когда/что/old→new») коммитится там же. Чтения идут через
+:meth:`Database.read` — под тем же ``RLock``, что и транзакции (#54), поэтому
+читатель не видит незафиксированных строк и состояния, которое затем будет
+откачено, и не может получить перемешанный результат операторов другого потока.
+"""
+
+from __future__ import annotations
+
+import sqlite3
+from dataclasses import replace
+from typing import cast
+
+from . import audit, validation
+from .clock import utcnow
+from .db import Database
+from .errors import StorageError
+from .models import (
+    AuditEntry,
+    ConfigMeta,
+    Device,
+    Entity,
+    GeoIpSchedule,
+    Mode,
+    Rule,
+    RuleException,
+)
+
+
+def _rule_from_row(row: sqlite3.Row) -> Rule:
+    return Rule(
+        id=int(row["id"]),
+        name=str(row["name"]),
+        kind=str(row["kind"]),
+        match=str(row["match"]),
+        target=str(row["target"]),
+        priority=int(row["priority"]),
+        enabled=bool(row["enabled"]),
+        created_at=str(row["created_at"]),
+        updated_at=str(row["updated_at"]),
+    )
+
+
+def _exception_from_row(row: sqlite3.Row) -> RuleException:
+    return RuleException(
+        id=int(row["id"]),
+        match=str(row["match"]),
+        reason=str(row["reason"]),
+        enabled=bool(row["enabled"]),
+        created_at=str(row["created_at"]),
+        updated_at=str(row["updated_at"]),
+    )
+
+
+def _config_from_row(row: sqlite3.Row) -> ConfigMeta:
+    return ConfigMeta(
+        id=int(row["id"]),
+        name=str(row["name"]),
+        path=str(row["path"]),
+        version=int(row["version"]),
+        checksum=str(row["checksum"]),
+        size_bytes=int(row["size_bytes"]),
+        applied=bool(row["applied"]),
+        created_at=str(row["created_at"]),
+        updated_at=str(row["updated_at"]),
+    )
+
+
+def _device_from_row(row: sqlite3.Row) -> Device:
+    return Device(
+        id=int(row["id"]),
+        mac=str(row["mac"]),
+        name=str(row["name"]),
+        address=str(row["address"]),
+        policy=str(row["policy"]),
+        last_seen=None if row["last_seen"] is None else str(row["last_seen"]),
+        created_at=str(row["created_at"]),
+        updated_at=str(row["updated_at"]),
+    )
+
+
+def _geoip_from_row(conn: sqlite3.Connection) -> GeoIpSchedule:
+    row = conn.execute(
+        "SELECT enabled, cron, provider, updated_at FROM geoip_schedule WHERE id = 1"
+    ).fetchone()
+    if row is None:
+        return GeoIpSchedule()
+    return GeoIpSchedule(
+        enabled=bool(row["enabled"]),
+        cron=str(row["cron"]),
+        provider=str(row["provider"]),
+        updated_at=str(row["updated_at"]),
+    )
+
+
+class Store:
+    """Доступ к состоянию: чтение + аудируемые мутации."""
+
+    def __init__(self, db: Database) -> None:
+        self._db = db
+
+    @property
+    def database(self) -> Database:
+        return self._db
+
+    # -- чтение ---------------------------------------------------------
+    # Чтения идут через Database.read() под тем же RLock, что транзакции
+    # (#54): это исключает перемешивание операторов разных потоков и грязные
+    # чтения незафиксированных строк.
+    def get_mode(self) -> Mode:
+        with self._db.read() as conn:
+            row = conn.execute("SELECT mode FROM routing_mode WHERE id = 1").fetchone()
+        if row is None:
+            return Mode.OFF
+        return Mode(str(row["mode"]))
+
+    def get_geoip_schedule(self) -> GeoIpSchedule:
+        with self._db.read() as conn:
+            return _geoip_from_row(conn)
+
+    def list_rules(self, *, enabled_only: bool = False) -> list[Rule]:
+        sql = "SELECT * FROM routing_rules"
+        if enabled_only:
+            sql += " WHERE enabled = 1"
+        sql += " ORDER BY priority, id"
+        with self._db.read() as conn:
+            rows = conn.execute(sql).fetchall()
+        return [_rule_from_row(row) for row in rows]
+
+    def get_rule(self, rule_id: int) -> Rule | None:
+        with self._db.read() as conn:
+            row = conn.execute("SELECT * FROM routing_rules WHERE id = ?", (rule_id,)).fetchone()
+        return None if row is None else _rule_from_row(row)
+
+    def get_rule_by_name(self, name: str) -> Rule | None:
+        with self._db.read() as conn:
+            row = conn.execute("SELECT * FROM routing_rules WHERE name = ?", (name,)).fetchone()
+        return None if row is None else _rule_from_row(row)
+
+    def list_exceptions(self) -> list[RuleException]:
+        with self._db.read() as conn:
+            rows = conn.execute("SELECT * FROM rule_exceptions ORDER BY id").fetchall()
+        return [_exception_from_row(row) for row in rows]
+
+    def get_exception(self, match: str) -> RuleException | None:
+        with self._db.read() as conn:
+            row = conn.execute("SELECT * FROM rule_exceptions WHERE match = ?", (match,)).fetchone()
+        return None if row is None else _exception_from_row(row)
+
+    def list_configs(self) -> list[ConfigMeta]:
+        with self._db.read() as conn:
+            rows = conn.execute("SELECT * FROM configs ORDER BY name").fetchall()
+        return [_config_from_row(row) for row in rows]
+
+    def get_config(self, name: str) -> ConfigMeta | None:
+        with self._db.read() as conn:
+            row = conn.execute("SELECT * FROM configs WHERE name = ?", (name,)).fetchone()
+        return None if row is None else _config_from_row(row)
+
+    def list_devices(self) -> list[Device]:
+        with self._db.read() as conn:
+            rows = conn.execute("SELECT * FROM devices ORDER BY name").fetchall()
+        return [_device_from_row(row) for row in rows]
+
+    def get_device(self, mac: str) -> Device | None:
+        normalized = validation.normalize_mac(mac)
+        with self._db.read() as conn:
+            row = conn.execute("SELECT * FROM devices WHERE mac = ?", (normalized,)).fetchone()
+        return None if row is None else _device_from_row(row)
+
+    def list_audit(
+        self, *, entity: str | None = None, entity_id: str | int | None = None, limit: int = 100
+    ) -> list[AuditEntry]:
+        with self._db.read() as conn:
+            return audit.list_entries(conn, entity=entity, entity_id=entity_id, limit=limit)
+
+    # -- мутации: правила ------------------------------------------------
+    def upsert_rule(self, rule: Rule, *, actor: str) -> Rule:
+        """Создать или обновить правило (по ``id`` либо по уникальному ``name``)."""
+        validation.validate_name("name", rule.name)
+        kind = validation.validate_rule_kind(rule.kind)
+        match = validation.validate_match(kind, rule.match)
+        target = validation.validate_target(rule.target)
+        priority = validation.validate_priority(rule.priority)
+        now = utcnow()
+        with self._db.transaction() as conn:
+            existing = self._find_rule_row(conn, rule.id, rule.name)
+            core: tuple[str, str, str, str, int, int] = (
+                rule.name,
+                kind,
+                match,
+                target,
+                priority,
+                1 if rule.enabled else 0,
+            )
+            if existing is None:
+                cursor = conn.execute(
+                    "INSERT INTO routing_rules (name, kind, match, target, priority, enabled,"
+                    " created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
+                    (*core, now, now),
+                )
+                new_id = int(cursor.lastrowid or 0)
+                saved = replace(
+                    rule,
+                    id=new_id,
+                    kind=kind,
+                    match=match,
+                    target=target,
+                    priority=priority,
+                    created_at=now,
+                    updated_at=now,
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="create",
+                    entity=Entity.RULE.value,
+                    entity_id=new_id,
+                    old_value=None,
+                    new_value=saved.as_dict(),
+                )
+            else:
+                rule_id = int(existing["id"])
+                conn.execute(
+                    "UPDATE routing_rules SET name = ?, kind = ?, match = ?, target = ?,"
+                    " priority = ?, enabled = ?, updated_at = ? WHERE id = ?",
+                    (*core, now, rule_id),
+                )
+                saved = replace(
+                    rule,
+                    id=rule_id,
+                    kind=kind,
+                    match=match,
+                    target=target,
+                    priority=priority,
+                    created_at=str(existing["created_at"]),
+                    updated_at=now,
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="update",
+                    entity=Entity.RULE.value,
+                    entity_id=rule_id,
+                    old_value=_rule_from_row(existing).as_dict(),
+                    new_value=saved.as_dict(),
+                )
+            return saved
+
+    def delete_rule(self, rule_id: int, *, actor: str) -> bool:
+        """Удалить правило; ``False`` — если правила не было."""
+        with self._db.transaction() as conn:
+            row = self._find_rule_row(conn, rule_id, None)
+            if row is None:
+                return False
+            removed = _rule_from_row(row)
+            conn.execute("DELETE FROM routing_rules WHERE id = ?", (int(row["id"]),))
+            audit.record(
+                conn,
+                actor=actor,
+                action="delete",
+                entity=Entity.RULE.value,
+                entity_id=int(row["id"]),
+                old_value=removed.as_dict(),
+                new_value=None,
+            )
+        return True
+
+    @staticmethod
+    def _find_rule_row(
+        conn: sqlite3.Connection, rule_id: int | None, name: str | None
+    ) -> sqlite3.Row | None:
+        if rule_id is not None:
+            row = conn.execute("SELECT * FROM routing_rules WHERE id = ?", (rule_id,)).fetchone()
+            return cast("sqlite3.Row | None", row)
+        if name is not None:
+            row = conn.execute("SELECT * FROM routing_rules WHERE name = ?", (name,)).fetchone()
+            return cast("sqlite3.Row | None", row)
+        return None
+
+    # -- мутации: исключения ---------------------------------------------
+    def upsert_exception(self, exception: RuleException, *, actor: str) -> RuleException:
+        match = validation.validate_exception_match(exception.match)
+        now = utcnow()
+        with self._db.transaction() as conn:
+            existing = conn.execute(
+                "SELECT * FROM rule_exceptions WHERE match = ?", (match,)
+            ).fetchone()
+            if existing is None:
+                conn.execute(
+                    "INSERT INTO rule_exceptions (match, reason, enabled, created_at, updated_at)"
+                    " VALUES (?, ?, ?, ?, ?)",
+                    (match, exception.reason, 1 if exception.enabled else 0, now, now),
+                )
+            else:
+                conn.execute(
+                    "UPDATE rule_exceptions SET reason = ?, enabled = ?, updated_at = ?"
+                    " WHERE match = ?",
+                    (exception.reason, 1 if exception.enabled else 0, now, match),
+                )
+            row = conn.execute("SELECT * FROM rule_exceptions WHERE match = ?", (match,)).fetchone()
+            if row is None:  # pragma: no cover - невозможен после успешной записи
+                raise StorageError("правило-исключение исчезло сразу после записи")
+            saved = _exception_from_row(row)
+            audit.record(
+                conn,
+                actor=actor,
+                action="create" if existing is None else "update",
+                entity=Entity.EXCEPTION.value,
+                entity_id=saved.id,
+                old_value=None if existing is None else _exception_from_row(existing).as_dict(),
+                new_value=saved.as_dict(),
+            )
+            return saved
+
+    def delete_exception(self, exception_id: int, *, actor: str) -> bool:
+        with self._db.transaction() as conn:
+            row = conn.execute(
+                "SELECT * FROM rule_exceptions WHERE id = ?", (exception_id,)
+            ).fetchone()
+            if row is None:
+                return False
+            removed = _exception_from_row(row)
+            conn.execute("DELETE FROM rule_exceptions WHERE id = ?", (exception_id,))
+            audit.record(
+                conn,
+                actor=actor,
+                action="delete",
+                entity=Entity.EXCEPTION.value,
+                entity_id=exception_id,
+                old_value=removed.as_dict(),
+                new_value=None,
+            )
+        return True
+
+    # -- мутации: режим и GeoIP ------------------------------------------
+    def set_mode(self, mode: str | Mode, *, actor: str) -> Mode:
+        """Установить режим маршрутизации; в журнал пишется old→new."""
+        validated = validation.validate_mode(mode)
+        with self._db.transaction() as conn:
+            previous = conn.execute("SELECT mode FROM routing_mode WHERE id = 1").fetchone()
+            old = "off" if previous is None else str(previous["mode"])
+            now = utcnow()
+            conn.execute(
+                "INSERT INTO routing_mode (id, mode, updated_at) VALUES (1, ?, ?)"
+                " ON CONFLICT(id) DO UPDATE SET mode = excluded.mode,"
+                " updated_at = excluded.updated_at",
+                (validated.value, now),
+            )
+            audit.record(
+                conn,
+                actor=actor,
+                action="set_mode",
+                entity=Entity.MODE.value,
+                entity_id=1,
+                old_value={"mode": old},
+                new_value={"mode": validated.value},
+            )
+        return validated
+
+    def set_geoip_schedule(
+        self,
+        *,
+        enabled: bool | None = None,
+        cron: str | None = None,
+        provider: str | None = None,
+        actor: str,
+    ) -> GeoIpSchedule:
+        """Обновить расписание GeoIP (частичное обновление) и записать аудит."""
+        now = utcnow()
+        with self._db.transaction() as conn:
+            # чтение old_value — внутри той же транзакции, что и запись (#55 D-2):
+            # иначе при конкурентном обновлении журнал заявит устаревшее «старое».
+            current = _geoip_from_row(conn)
+            stored = GeoIpSchedule(
+                enabled=current.enabled if enabled is None else enabled,
+                cron=validation.validate_cron(current.cron if cron is None else cron),
+                provider=validation.validate_provider(
+                    current.provider if provider is None else provider
+                ),
+                updated_at=now,
+            )
+            conn.execute(
+                "INSERT INTO geoip_schedule (id, enabled, cron, provider, updated_at)"
+                " VALUES (1, ?, ?, ?, ?)"
+                " ON CONFLICT(id) DO UPDATE SET enabled = excluded.enabled, cron = excluded.cron,"
+                " provider = excluded.provider, updated_at = excluded.updated_at",
+                (1 if stored.enabled else 0, stored.cron, stored.provider, now),
+            )
+            audit.record(
+                conn,
+                actor=actor,
+                action="set_geoip_schedule",
+                entity=Entity.GEOIP_SCHEDULE.value,
+                entity_id=1,
+                old_value=current.as_dict(),
+                new_value=stored.as_dict(),
+            )
+        return stored
+
+    # -- мутации: конфиги -------------------------------------------------
+    def upsert_config(self, config: ConfigMeta, *, actor: str) -> ConfigMeta:
+        name = validation.validate_name("name", config.name)
+        path = validation.validate_config_path(config.path)
+        now = utcnow()
+        with self._db.transaction() as conn:
+            existing = conn.execute("SELECT * FROM configs WHERE name = ?", (name,)).fetchone()
+            if existing is None:
+                cursor = conn.execute(
+                    "INSERT INTO configs (name, version, path, checksum, size_bytes, applied,"
+                    " created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
+                    (
+                        name,
+                        config.version,
+                        path,
+                        config.checksum,
+                        config.size_bytes,
+                        1 if config.applied else 0,
+                        now,
+                        now,
+                    ),
+                )
+                config_id = int(cursor.lastrowid or 0)
+                saved = replace(
+                    config, id=config_id, name=name, path=path, created_at=now, updated_at=now
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="create",
+                    entity=Entity.CONFIG.value,
+                    entity_id=config_id,
+                    old_value=None,
+                    new_value=saved.as_dict(),
+                )
+            else:
+                config_id = int(existing["id"])
+                conn.execute(
+                    "UPDATE configs SET version = ?, path = ?, checksum = ?, size_bytes = ?,"
+                    " applied = ?, updated_at = ? WHERE id = ?",
+                    (
+                        config.version,
+                        path,
+                        config.checksum,
+                        config.size_bytes,
+                        1 if config.applied else 0,
+                        now,
+                        config_id,
+                    ),
+                )
+                saved = replace(
+                    config,
+                    id=config_id,
+                    name=name,
+                    path=path,
+                    created_at=str(existing["created_at"]),
+                    updated_at=now,
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="update",
+                    entity=Entity.CONFIG.value,
+                    entity_id=config_id,
+                    old_value=_config_from_row(existing).as_dict(),
+                    new_value=saved.as_dict(),
+                )
+            return saved
+
+    def mark_config_applied(self, name: str, *, applied: bool, actor: str) -> ConfigMeta:
+        """Отметить конфиг применённым/снятым и записать аудит."""
+        with self._db.transaction() as conn:
+            row = conn.execute("SELECT * FROM configs WHERE name = ?", (name,)).fetchone()
+            if row is None:
+                raise StorageError(f"конфиг {name!r} не найден")
+            now = utcnow()
+            conn.execute(
+                "UPDATE configs SET applied = ?, updated_at = ? WHERE id = ?",
+                (1 if applied else 0, now, int(row["id"])),
+            )
+            updated = replace(_config_from_row(row), applied=applied, updated_at=now)
+            audit.record(
+                conn,
+                actor=actor,
+                action="set_applied",
+                entity=Entity.CONFIG.value,
+                entity_id=int(row["id"]),
+                old_value=_config_from_row(row).as_dict(),
+                new_value=updated.as_dict(),
+            )
+            return updated
+
+    # -- мутации: устройства ----------------------------------------------
+    def register_device(self, device: Device, *, actor: str) -> Device:
+        mac = validation.normalize_mac(device.mac)
+        name = validation.validate_name("name", device.name)
+        policy = validation.validate_device_policy(device.policy)
+        now = utcnow()
+        with self._db.transaction() as conn:
+            existing = conn.execute("SELECT * FROM devices WHERE mac = ?", (mac,)).fetchone()
+            if existing is None:
+                cursor = conn.execute(
+                    "INSERT INTO devices (mac, name, address, policy, last_seen, created_at,"
+                    " updated_at) VALUES (?, ?, ?, ?, ?, ?, ?)",
+                    (mac, name, device.address, policy, device.last_seen, now, now),
+                )
+                device_id = int(cursor.lastrowid or 0)
+                saved = replace(
+                    device,
+                    id=device_id,
+                    mac=mac,
+                    name=name,
+                    policy=policy,
+                    created_at=now,
+                    updated_at=now,
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="create",
+                    entity=Entity.DEVICE.value,
+                    entity_id=device_id,
+                    old_value=None,
+                    new_value=saved.as_dict(),
+                )
+            else:
+                device_id = int(existing["id"])
+                conn.execute(
+                    "UPDATE devices SET name = ?, address = ?, policy = ?, last_seen = ?,"
+                    " updated_at = ? WHERE id = ?",
+                    (name, device.address, policy, device.last_seen, now, device_id),
+                )
+                saved = replace(
+                    device,
+                    id=device_id,
+                    mac=mac,
+                    name=name,
+                    policy=policy,
+                    created_at=str(existing["created_at"]),
+                    updated_at=now,
+                )
+                audit.record(
+                    conn,
+                    actor=actor,
+                    action="update",
+                    entity=Entity.DEVICE.value,
+                    entity_id=device_id,
+                    old_value=_device_from_row(existing).as_dict(),
+                    new_value=saved.as_dict(),
+                )
+            return saved
+
+    def delete_device(self, mac: str, *, actor: str) -> bool:
+        normalized = validation.normalize_mac(mac)
+        with self._db.transaction() as conn:
+            row = conn.execute("SELECT * FROM devices WHERE mac = ?", (normalized,)).fetchone()
+            if row is None:
+                return False
+            removed = _device_from_row(row)
+            conn.execute("DELETE FROM devices WHERE mac = ?", (normalized,))
+            audit.record(
+                conn,
+                actor=actor,
+                action="delete",
+                entity=Entity.DEVICE.value,
+                entity_id=removed.id,
+                old_value=removed.as_dict(),
+                new_value=None,
+            )
+        return True
+
+    # -- служебное --------------------------------------------------------
+    def counts(self) -> dict[str, int]:
+        """Количество строк в изменяемых таблицах (для отчётов и тестов)."""
+        tables = {
+            "rules": "routing_rules",
+            "exceptions": "rule_exceptions",
+            "configs": "configs",
+            "devices": "devices",
+            "audit": "audit_log",
+            "snapshots": "state_snapshots",
+        }
+        result: dict[str, int] = {}
+        with self._db.read() as conn:  # один снимок на все таблицы: счётчики согласованы
+            for key, table in tables.items():
+                row = conn.execute(f"SELECT COUNT(*) FROM {table}").fetchone()  # noqa: S608
+                result[key] = int(row[0]) if row is not None else 0
+        return result
+
+    def raw(self) -> sqlite3.Connection:
+        """Соединение для кода, которому нужен доступ ниже уровня репозитория.
+
+        Лок не берётся: в рантайме используйте :meth:`Database.read` /
+        :meth:`Database.transaction` (#54), иначе возможны гонки на общем
+        соединении. Метод оставлен для однопоточного кода и миграций.
+        """
+        return self._db.connection

backend/awg_api/store/service.py

@@ -0,0 +1,47 @@
+"""Точка входа слоя хранения: открыть БД, применить миграции, собрать движок."""
+
+from __future__ import annotations
+
+import os
+from dataclasses import dataclass
+
+from .apply import Applier, ApplyEngine
+from .db import Database
+from .repository import Store
+from .state import StateSnapshot
+
+
+@dataclass(slots=True)
+class Storage:
+    """Собранный слой хранения для приложения."""
+
+    db: Database
+    store: Store
+    engine: ApplyEngine
+
+    def close(self) -> None:
+        self.db.close()
+
+    def __enter__(self) -> Storage:
+        return self
+
+    def __exit__(self, *exc_info: object) -> None:
+        self.close()
+
+
+def open_storage(
+    path: str | os.PathLike[str] | None = None,
+    *,
+    applier: Applier | None = None,
+    actor: str = "system",
+    auto_migrate: bool = True,
+) -> Storage:
+    """Открыть хранилище: на пустом ``/data`` схема поднимается автоматически."""
+    db = Database(path, auto_migrate=auto_migrate)
+    store = Store(db)
+    return Storage(db=db, store=store, engine=ApplyEngine(store, applier, actor=actor))
+
+
+def rollback_to(engine: ApplyEngine, plan_id: int, *, reason: str = "") -> StateSnapshot:
+    """Явный откат состояния к снимку плана (тонкая обёртка для API)."""
+    return engine.rollback(plan_id, reason=reason)

backend/awg_api/store/state.py

@@ -0,0 +1,174 @@
+"""Снимки состояния и восстановление после отката (rollback, issue #20).
+
+Снимок — это JSON-копия состояния (режим, расписание GeoIP, правила,
+исключения) на момент перед применением. Снимок сохраняется ДО мутации,
+поэтому даже при неудачном apply (внешний iptables упал) есть источник для
+восстановления.
+"""
+
+from __future__ import annotations
+
+import json
+import sqlite3
+from dataclasses import dataclass
+from typing import Any
+
+from . import audit
+from .clock import utcnow
+from .errors import StorageError
+from .models import Entity
+
+
+@dataclass(frozen=True, slots=True)
+class StateSnapshot:
+    """Сохранённый снимок состояния."""
+
+    id: int
+    entity: str
+    entity_id: str
+    created_at: str
+    payload: dict[str, Any]
+    reason: str
+
+
+def capture_state(conn: sqlite3.Connection, *, include_exceptions: bool = True) -> dict[str, Any]:
+    """Снять текущее состояние в виде JSON-совместимого словаря."""
+    mode_row = conn.execute("SELECT mode FROM routing_mode WHERE id = 1").fetchone()
+    geoip_row = conn.execute(
+        "SELECT enabled, cron, provider FROM geoip_schedule WHERE id = 1"
+    ).fetchone()
+    rules = [
+        {
+            "name": str(row["name"]),
+            "kind": str(row["kind"]),
+            "match": str(row["match"]),
+            "target": str(row["target"]),
+            "priority": int(row["priority"]),
+            "enabled": bool(row["enabled"]),
+        }
+        for row in conn.execute(
+            "SELECT name, kind, match, target, priority, enabled FROM routing_rules"
+            " ORDER BY priority, id"
+        ).fetchall()
+    ]
+    payload: dict[str, Any] = {
+        "mode": "off" if mode_row is None else str(mode_row["mode"]),
+        "geoip": {
+            "enabled": True if geoip_row is None else bool(geoip_row["enabled"]),
+            "cron": "0 4 * * *" if geoip_row is None else str(geoip_row["cron"]),
+            "provider": "ripe" if geoip_row is None else str(geoip_row["provider"]),
+        },
+        "rules": rules,
+    }
+    if include_exceptions:
+        payload["exceptions"] = [
+            {
+                "match": str(row["match"]),
+                "reason": str(row["reason"]),
+                "enabled": bool(row["enabled"]),
+            }
+            for row in conn.execute(
+                "SELECT match, reason, enabled FROM rule_exceptions ORDER BY id"
+            ).fetchall()
+        ]
+    return payload
+
+
+def save_snapshot(
+    conn: sqlite3.Connection,
+    payload: dict[str, Any],
+    *,
+    entity: str = Entity.APPLY.value,
+    entity_id: str = "state",
+    reason: str = "",
+) -> int:
+    """Сохранить снимок состояния и вернуть идентификатор."""
+    cursor = conn.execute(
+        "INSERT INTO state_snapshots (entity, entity_id, created_at, payload, reason)"
+        " VALUES (?, ?, ?, ?, ?)",
+        (entity, entity_id, utcnow(), json.dumps(payload, sort_keys=True), reason),
+    )
+    return int(cursor.lastrowid or 0)
+
+
+def load_snapshot(conn: sqlite3.Connection, snapshot_id: int) -> StateSnapshot:
+    """Прочитать снимок по id."""
+    row = conn.execute("SELECT * FROM state_snapshots WHERE id = ?", (snapshot_id,)).fetchone()
+    if row is None:
+        raise StorageError(f"снимок состояния {snapshot_id} не найден")
+    return StateSnapshot(
+        id=int(row["id"]),
+        entity=str(row["entity"]),
+        entity_id=str(row["entity_id"]),
+        created_at=str(row["created_at"]),
+        payload=json.loads(str(row["payload"])),
+        reason=str(row["reason"]),
+    )
+
+
+def restore_state(conn: sqlite3.Connection, payload: dict[str, Any]) -> None:
+    """Полностью заменить изменяемые таблицы состоянием из снимка."""
+    conn.execute("DELETE FROM routing_rules")
+    for rule in payload.get("rules", []):
+        conn.execute(
+            "INSERT INTO routing_rules (name, kind, match, target, priority, enabled,"
+            " created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
+            (
+                rule["name"],
+                rule["kind"],
+                rule["match"],
+                rule["target"],
+                int(rule["priority"]),
+                1 if rule["enabled"] else 0,
+                utcnow(),
+                utcnow(),
+            ),
+        )
+    if "exceptions" in payload:
+        conn.execute("DELETE FROM rule_exceptions")
+        for exception in payload["exceptions"]:
+            conn.execute(
+                "INSERT INTO rule_exceptions (match, reason, enabled, created_at, updated_at)"
+                " VALUES (?, ?, ?, ?, ?)",
+                (
+                    exception["match"],
+                    exception.get("reason", ""),
+                    1 if exception["enabled"] else 0,
+                    utcnow(),
+                    utcnow(),
+                ),
+            )
+    geoip = payload.get("geoip", {})
+    conn.execute(
+        "UPDATE routing_mode SET mode = ?, updated_at = ? WHERE id = 1",
+        (payload.get("mode", "off"), utcnow()),
+    )
+    conn.execute(
+        "UPDATE geoip_schedule SET enabled = ?, cron = ?, provider = ?,"
+        " updated_at = ? WHERE id = 1",
+        (
+            1 if geoip.get("enabled", True) else 0,
+            geoip.get("cron", "0 4 * * *"),
+            geoip.get("provider", "ripe"),
+            utcnow(),
+        ),
+    )
+
+
+def rollback_to_snapshot(
+    conn: sqlite3.Connection, snapshot_id: int, *, actor: str, reason: str = ""
+) -> StateSnapshot:
+    """Восстановить состояние из снимка и записать это в журнал аудита."""
+    snapshot = load_snapshot(conn, snapshot_id)
+    audit.record(
+        conn,
+        actor=actor,
+        action="rollback",
+        entity=snapshot.entity,
+        entity_id=snapshot.entity_id,
+        old_value=capture_state(conn),
+        new_value=snapshot.payload,
+        detail=reason or f"rollback к снимку #{snapshot.id}",
+    )
+    restore_state(conn, snapshot.payload)
+    return snapshot

backend/awg_api/store/validation.py

@@ -0,0 +1,131 @@
+"""Чистые функции валидации состояния (стадия ``validate`` перед apply, issue #20).
+
+Валидация отделена от БД: те же функции вызывают и репозиторий (точечные
+мутации), и движок атомарного применения (``validate -> stage -> apply``).
+"""
+
+from __future__ import annotations
+
+import ipaddress
+import re
+
+from .errors import ValidationError
+from .models import DEVICE_POLICIES, RULE_KINDS, Mode
+
+_NAME_RE = re.compile(r"^[a-z0-9][a-z0-9_.:-]{0,62}$")
+_DOMAIN_RE = re.compile(r"^(\*\.)?([a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?\.)+[a-z]{2,63}$")
+_IPSET_RE = re.compile(r"^[A-Za-z0-9][A-Za-z0-9_.:-]{0,63}$")
+_MAC_RE = re.compile(r"^(?:[0-9a-f]{2}:){5}[0-9a-f]{2}$")
+_CRON_FIELD_RE = re.compile(r"^[0-9*,/-]{1,20}$")
+_PROVIDER_RE = re.compile(r"^[a-z0-9][a-z0-9_.-]{0,31}$")
+
+
+def normalize_mac(mac: str) -> str:
+    """Привести MAC к канонической форме ``aa:bb:cc:dd:ee:ff``."""
+    cleaned = mac.strip().replace("-", ":").lower()
+    if len(cleaned) == 12 and ":" not in cleaned:
+        cleaned = ":".join(cleaned[i : i + 2] for i in range(0, 12, 2))
+    if not _MAC_RE.match(cleaned):
+        raise ValidationError("mac", f"некорректный MAC-адрес: {mac!r}")
+    return cleaned
+
+
+def validate_name(field: str, value: str) -> str:
+    """Проверить идентификатор (имя правила/конфига устройства)."""
+    if not _NAME_RE.match(value.strip()):
+        raise ValidationError(
+            field, f"допустимы строчные латинские буквы, цифры и «_.:-», до 63 символов: {value!r}"
+        )
+    return value.strip()
+
+
+def validate_rule_kind(kind: str) -> str:
+    if kind not in RULE_KINDS:
+        raise ValidationError("kind", f"ожидается одно из {RULE_KINDS}, получено {kind!r}")
+    return kind
+
+
+def validate_match(kind: str, match: str) -> str:
+    """Проверить образец правила по типу записи."""
+    validate_rule_kind(kind)
+    value = match.strip()
+    if not value:
+        raise ValidationError("match", "образец правила не может быть пустым")
+    if kind == "domain":
+        if not _DOMAIN_RE.match(value):
+            raise ValidationError("match", f"некорректный домен: {value!r}")
+    elif kind == "cidr":
+        try:
+            ipaddress.ip_network(value, strict=False)
+        except ValueError as exc:
+            raise ValidationError("match", f"некорректная сеть CIDR: {value!r}") from exc
+    elif not _IPSET_RE.match(value):
+        raise ValidationError("match", f"некорректное имя ipset: {value!r}")
+    return value
+
+
+def validate_exception_match(match: str) -> str:
+    """Проверить образец исключения: домен, имя ipset или сеть CIDR."""
+    value = match.strip()
+    if not value:
+        raise ValidationError("match", "образец исключения не может быть пустым")
+    if _DOMAIN_RE.match(value) or _IPSET_RE.match(value):
+        return value
+    try:
+        ipaddress.ip_network(value, strict=False)
+    except ValueError as exc:
+        raise ValidationError(
+            "match", f"ожидается домен, сеть CIDR или имя ipset: {match!r}"
+        ) from exc
+    return value
+
+
+def validate_target(target: str) -> str:
+    value = target.strip()
+    if not _IPSET_RE.match(value):
+        raise ValidationError("target", f"некорректная цель маршрутизации: {target!r}")
+    return value
+
+
+def validate_priority(priority: int) -> int:
+    if not isinstance(priority, int) or isinstance(priority, bool):
+        raise ValidationError("priority", f"ожидается целое число, получено {priority!r}")
+    if not 0 <= priority <= 65535:
+        raise ValidationError("priority", f"вне диапазона 0..65535: {priority}")
+    return priority
+
+
+def validate_mode(mode: str | Mode) -> Mode:
+    try:
+        return Mode(mode)
+    except ValueError as exc:
+        raise ValidationError(
+            "mode", f"ожидается одно из {Mode.values()}, получено {mode!r}"
+        ) from exc
+
+
+def validate_cron(cron: str) -> str:
+    fields = cron.split()
+    if len(fields) != 5 or not all(_CRON_FIELD_RE.match(part) for part in fields):
+        raise ValidationError("cron", f"ожидается 5-полевое cron-выражение: {cron!r}")
+    return " ".join(fields)
+
+
+def validate_provider(provider: str) -> str:
+    value = provider.strip().lower()
+    if not _PROVIDER_RE.match(value):
+        raise ValidationError("provider", f"некорректное имя провайдера GeoIP: {provider!r}")
+    return value
+
+
+def validate_device_policy(policy: str) -> str:
+    if policy not in DEVICE_POLICIES:
+        raise ValidationError("policy", f"ожидается одно из {DEVICE_POLICIES}, получено {policy!r}")
+    return policy
+
+
+def validate_config_path(path: str) -> str:
+    value = path.strip()
+    if not value.startswith("/") or ".." in value.split("/"):
+        raise ValidationError("path", f"ожидается абсолютный путь без «..»: {path!r}")
+    return value

backend/tests/test_store_apply.py

@@ -0,0 +1,311 @@
+"""Тесты атомарного применения: validate -> stage -> apply -> rollback (issue #20)."""
+
+from __future__ import annotations
+
+from collections.abc import Mapping
+from pathlib import Path
+from typing import Any
+
+import pytest
+
+from awg_api.store import (
+    AUDIT_STATUS_FAILED,
+    AUDIT_STATUS_OK,
+    AUDIT_STATUS_STAGED,
+    ApplyEngine,
+    ApplyError,
+    Database,
+    DesiredState,
+    Entity,
+    GeoIpSchedule,
+    Mode,
+    NullApplier,
+    Rule,
+    RuleException,
+    Store,
+    ValidationError,
+    capture_state,
+)
+
+
+class MockIptables:
+    """Мок внешнего применителя: умеет «падать» как реальный iptables."""
+
+    def __init__(self, *, fail_apply: bool = False, fail_revert: bool = False) -> None:
+        self.applied: list[dict[str, Any]] = []
+        self.reverted: list[dict[str, Any]] = []
+        self.fail_apply = fail_apply
+        self.fail_revert = fail_revert
+
+    def apply(self, payload: Mapping[str, Any]) -> None:
+        if self.fail_apply:
+            self.applied.append(dict(payload))
+            raise RuntimeError("mock iptables: exit 4")
+        self.applied.append(dict(payload))
+
+    def revert(self, payload: Mapping[str, Any]) -> None:
+        if self.fail_revert:
+            raise RuntimeError("mock iptables: revert failed")
+        self.reverted.append(dict(payload))
+
+
+def make_engine(
+    tmp_path: Path, applier: MockIptables | None = None
+) -> tuple[Database, Store, ApplyEngine, MockIptables]:
+    db = Database(tmp_path / "data" / "awg-dash.db")
+    store = Store(db)
+    mock = applier if applier is not None else MockIptables()
+    return db, store, ApplyEngine(store, mock, actor="ui:admin"), mock
+
+
+def desired(*rules: Rule, mode: Mode = Mode.SPLIT) -> DesiredState:
+    return DesiredState(mode=mode, rules=rules, geoip=GeoIpSchedule())
+
+
+# -- validate ------------------------------------------------------------------
+def test_validate_accepts_good_state(tmp_path: Path) -> None:
+    db, _store, engine, _mock = make_engine(tmp_path)
+    with db:
+        state = desired(Rule(name="yt", kind="domain", match="youtube.com", target="tun0"))
+        assert engine.validate(state) is state
+
+
+def test_validate_rejects_bad_state(tmp_path: Path) -> None:
+    db, _store, engine, _mock = make_engine(tmp_path)
+    with db:
+        cases: list[DesiredState] = [
+            DesiredState(mode="turbo"),  # type: ignore[arg-type]
+            desired(Rule(name="dup", kind="domain", match="a.example.com", target="tun0"),
+                    Rule(name="dup", kind="domain", match="b.example.com", target="tun0")),
+            desired(Rule(name="x", kind="cidr", match="10.0.0.0/99", target="tun0")),
+            DesiredState(mode=Mode.SPLIT, rules=(), geoip=GeoIpSchedule(cron="всякий раз")),
+            DesiredState(
+                mode=Mode.SPLIT,
+                rules=(),
+                geoip=GeoIpSchedule(),
+                exceptions=(RuleException(match="!!!"),),
+            ),
+            DesiredState(mode=Mode.SPLIT, rules=(), geoip=GeoIpSchedule(provider="!")),
+        ]
+        for case in cases:
+            with pytest.raises(ValidationError):
+                engine.validate(case)
+
+
+def test_validate_does_not_touch_database(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(tmp_path)
+    with db:
+        with pytest.raises(ValidationError):
+            engine.apply_payload({"mode": "split", "rules": [{"name": "x", "kind": "cidr",
+                                                              "match": "bad", "target": "tun0"}]})
+        assert store.counts() == {
+            "rules": 0,
+            "exceptions": 0,
+            "configs": 0,
+            "devices": 0,
+            "audit": 0,
+            "snapshots": 0,
+        }
+
+
+# -- stage ---------------------------------------------------------------------
+def test_stage_saves_snapshot_and_staged_audit(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(tmp_path)
+    with db:
+        store.upsert_rule(Rule(name="old", kind="domain", match="old.example.com", target="tun0"),
+                          actor="system")
+        store.set_mode(Mode.OFF, actor="system")
+        before = capture_state(db.connection)
+
+        plan = engine.stage(desired(Rule(name="new", kind="domain", match="new.example.com",
+                                         target="tun0")), reason="тест")
+
+        assert plan.previous == before
+        assert plan.desired.mode == Mode.SPLIT
+        # состояние ещё не изменено
+        assert capture_state(db.connection) == before
+        assert [rule.name for rule in store.list_rules()] == ["old"]
+        snapshots = store.counts()["snapshots"]
+        assert snapshots == 1
+        staged = store.list_audit(entity=Entity.APPLY.value)[0]
+        assert staged.status == AUDIT_STATUS_STAGED
+        assert staged.action == "stage"
+        assert staged.detail == "тест"
+        assert staged.old_value == before
+
+
+def test_stage_rejects_invalid_state_without_snapshot(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(tmp_path)
+    with db:
+        with pytest.raises(ValidationError):
+            engine.stage(DesiredState(mode=Mode.SPLIT, rules=(), geoip=GeoIpSchedule(cron="bad")))
+        assert store.counts()["snapshots"] == 0
+
+
+# -- apply ---------------------------------------------------------------------
+def test_apply_writes_state_and_audit(tmp_path: Path) -> None:
+    db, store, engine, mock = make_engine(tmp_path)
+    with db:
+        plan = engine.stage(desired(Rule(name="yt", kind="domain", match="youtube.com", target="tun0"),
+                                    mode=Mode.FULL), reason="включение")
+        result = engine.apply(plan)
+
+        assert result.ok is True
+        assert result.plan_id == plan.plan_id
+        assert result.audit_id > 0
+        assert store.get_mode() == Mode.FULL
+        assert [rule.name for rule in store.list_rules()] == ["yt"]
+        assert mock.applied == [plan.desired.to_payload()]
+        entry = store.list_audit(entity=Entity.APPLY.value)[0]
+        assert entry.status == AUDIT_STATUS_OK
+        assert entry.action == "apply"
+        assert entry.old_value == plan.previous
+        assert entry.new_value == plan.desired.to_payload()
+
+
+def test_failed_apply_restores_previous_state(tmp_path: Path) -> None:
+    """GIVEN ошибочный apply (мок падения iptables), THEN состояние прежнее + ApplyError."""
+    db, store, engine, mock = make_engine(tmp_path, MockIptables(fail_apply=True))
+    with db:
+        store.upsert_rule(Rule(name="keep", kind="domain", match="keep.example.com", target="tun0"),
+                          actor="system")
+        store.set_mode(Mode.SPLIT, actor="system")
+        store.set_geoip_schedule(cron="0 5 * * *", actor="system")
+        before = capture_state(db.connection)
+
+        plan = engine.stage(desired(Rule(name="new", kind="domain", match="new.example.com",
+                                         target="tun0"), mode=Mode.FULL), reason="сломается")
+
+        with pytest.raises(ApplyError) as excinfo:
+            engine.apply(plan)
+
+        error = excinfo.value
+        assert error.restored is True
+        assert error.audit_id is not None and error.audit_id > 0
+        # состояние, а не «частично применённая конфигурация»
+        assert capture_state(db.connection) == before
+        assert [rule.name for rule in store.list_rules()] == ["keep"]
+        assert store.get_mode() == Mode.SPLIT
+        assert store.get_geoip_schedule().cron == "0 5 * * *"
+
+        assert mock.reverted == [before]
+        failed = store.list_audit(entity=Entity.APPLY.value)[0]
+        assert failed.status == AUDIT_STATUS_FAILED
+        assert failed.id == error.audit_id
+        assert failed.new_value == before
+        assert "mock iptables" in (failed.detail or "")
+
+
+def test_failed_apply_with_failing_revert_still_restores_db(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(
+        tmp_path, MockIptables(fail_apply=True, fail_revert=True)
+    )
+    with db:
+        before = capture_state(db.connection)
+        plan = engine.stage(desired(Rule(name="x", kind="domain", match="x.example.com", target="tun0")))
+        with pytest.raises(ApplyError) as excinfo:
+            engine.apply(plan)
+        assert excinfo.value.restored is True
+        assert capture_state(db.connection) == before
+
+
+def test_apply_can_succeed_after_failed_apply(tmp_path: Path) -> None:
+    db, store, engine, mock = make_engine(tmp_path, MockIptables(fail_apply=True))
+    with db:
+        bad = engine.stage(desired(Rule(name="bad", kind="domain", match="bad.example.com",
+                                        target="tun0")))
+        with pytest.raises(ApplyError):
+            engine.apply(bad)
+
+        mock.fail_apply = False
+        good_rule = Rule(name="good", kind="domain", match="good.example.com", target="tun0")
+        result = engine.apply(engine.stage(desired(good_rule, mode=Mode.FULL)))
+        assert result.ok is True
+        assert [rule.name for rule in store.list_rules()] == ["good"]
+        assert store.get_mode() == Mode.FULL
+
+
+# -- rollback ------------------------------------------------------------------
+def test_rollback_returns_previous_state(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(tmp_path)
+    with db:
+        store.upsert_rule(Rule(name="old", kind="domain", match="old.example.com", target="tun0"),
+                          actor="ui:admin")
+        before = capture_state(db.connection)
+
+        result = engine.apply(
+            engine.stage(desired(Rule(name="new", kind="domain", match="new.example.com",
+                                      target="tun0"), mode=Mode.FULL), reason="применение"),
+        )
+        assert result.ok is True
+
+        snapshot = engine.rollback(result.plan_id, reason="откат оператором")
+        assert snapshot.id == result.plan_id
+        assert snapshot.payload == before
+        assert capture_state(db.connection) == before
+        assert [rule.name for rule in store.list_rules()] == ["old"]
+        assert store.get_mode() == Mode.OFF
+
+        rollback_entry = store.list_audit(entity=Entity.APPLY.value)[0]
+        assert rollback_entry.action == "rollback"
+        assert rollback_entry.detail == "откат оператором"
+        assert rollback_entry.new_value == before
+
+
+def test_apply_payload_sugar_and_null_applier(tmp_path: Path) -> None:
+    db, store, engine, _mock = make_engine(tmp_path)
+    with db:
+        result = engine.apply_payload(
+            {
+                "mode": "split",
+                "rules": [{"name": "yt", "kind": "domain", "match": "youtube.com", "target": "tun0"}],
+                "geoip": {"enabled": False, "cron": "0 3 * * *", "provider": "ripe"},
+                "exceptions": [{"match": "bank.example.com", "reason": "банк"}],
+            },
+            reason="api: применить",
+        )
+        assert result.ok is True
+        assert store.get_mode() == Mode.SPLIT
+        assert store.get_geoip_schedule().enabled is False
+        assert store.list_exceptions()[0].match == "bank.example.com"
+
+        engine_null = ApplyEngine(store, NullApplier(), actor="system")
+        assert engine_null.apply_payload({"mode": "off"}).ok is True
+        assert store.get_mode() == Mode.OFF
+
+
+def test_desired_state_payload_roundtrip() -> None:
+    state = DesiredState(
+        mode=Mode.FULL,
+        rules=(Rule(name="yt", kind="domain", match="youtube.com", target="tun0", priority=7),),
+        geoip=GeoIpSchedule(enabled=False, cron="0 1 * * *", provider="maxmind"),
+        exceptions=(RuleException(match="bank.example.com", reason="банк", enabled=False),),
+    )
+    restored = DesiredState.from_payload(state.to_payload())
+    assert restored.mode == Mode.FULL
+    assert restored.rules == state.rules
+    assert restored.geoip == state.geoip
+    assert restored.exceptions == state.exceptions
+
+
+@pytest.mark.parametrize(
+    "payload",
+    [
+        {"rules": "не список"},
+        {"rules": [{"kind": "domain", "match": "a.example.com", "target": "tun0"}]},
+        {"rules": ["строка"]},
+        {"exceptions": "не список"},
+        {"exceptions": [{"reason": "нет match"}]},
+        {"geoip": "не объект"},
+        {"mode": "turbo"},
+    ],
+)
+def test_desired_state_from_payload_rejects_bad_payload(payload: dict[str, Any]) -> None:
+    with pytest.raises(ValidationError):
+        DesiredState.from_payload(payload)
+
+
+def test_apply_engine_requires_store(tmp_path: Path) -> None:
+    db, _store, engine, _mock = make_engine(tmp_path)
+    with db:
+        assert engine.validate(desired()) == desired()

backend/tests/test_store_audit.py

@@ -0,0 +1,145 @@
+"""Тесты журнала аудита «кто/когда/что/old→new» (issue #20)."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from awg_api.store import (
+    AUDIT_STATUS_FAILED,
+    AUDIT_STATUS_OK,
+    Database,
+    Entity,
+    Mode,
+    Rule,
+    Store,
+)
+from awg_api.store import audit
+
+
+def make_db(tmp_path: Path) -> Database:
+    return Database(tmp_path / "data" / "awg-dash.db")
+
+
+def test_record_and_read_back(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        with db.transaction() as conn:
+            entry_id = audit.record(
+                conn,
+                actor="ui:admin",
+                action="update",
+                entity=Entity.RULE.value,
+                entity_id=7,
+                old_value={"match": "old.example.com"},
+                new_value={"match": "new.example.com"},
+            )
+        assert entry_id > 0
+        entries = audit.list_entries(db.connection)
+        assert len(entries) == 1
+        entry = entries[0]
+        assert entry.actor == "ui:admin"
+        assert entry.entity == "rule"
+        assert entry.entity_id == "7"
+        assert entry.old_value == {"match": "old.example.com"}
+        assert entry.new_value == {"match": "new.example.com"}
+        assert entry.status == AUDIT_STATUS_OK
+        assert entry.ts.endswith("Z")
+        assert entry.as_dict()["entity_id"] == "7"
+
+
+def test_actor_is_required(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        with db.transaction() as conn, pytest.raises(ValueError, match="actor"):
+            audit.record(
+                conn,
+                actor="",
+                action="update",
+                entity=Entity.RULE.value,
+                new_value={"x": 1},
+            )
+
+
+def test_old_and_new_can_be_absent(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        with db.transaction() as conn:
+            audit.record(conn, actor="system", action="noop", entity=Entity.APPLY.value)
+        entry = audit.last_entry(db.connection)
+        assert entry is not None
+        assert entry.old_value is None
+        assert entry.new_value is None
+        assert entry.entity_id is None
+        assert entry.detail is None
+
+
+def test_filters_limit_and_ordering(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        store = Store(db)
+        store.set_mode(Mode.SPLIT, actor="ui:admin")
+        store.set_mode(Mode.FULL, actor="ui:admin")
+        store.upsert_rule(Rule(name="yt", kind="domain", match="youtube.com", target="tun0"),
+                          actor="ui:admin")
+
+        mode_entries = audit.list_entries(db.connection, entity=Entity.MODE.value)
+        assert len(mode_entries) == 2
+        assert mode_entries[0].new_value == {"mode": "full"}  # свежие первыми
+        assert mode_entries[0].old_value == {"mode": "split"}
+
+        by_id = audit.list_entries(
+            db.connection, entity=Entity.MODE.value, entity_id=1, limit=1
+        )
+        assert len(by_id) == 1
+
+        assert audit.count(db.connection) == 3
+        assert audit.count(db.connection, entity=Entity.RULE.value) == 1
+        assert audit.last_entry(db.connection, entity=Entity.RULE.value) is not None
+
+
+def test_ts_can_be_overridden(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        with db.transaction() as conn:
+            audit.record(
+                conn,
+                actor="system",
+                action="stage",
+                entity=Entity.APPLY.value,
+                ts="2026-01-02T03:04:05.678Z",
+            )
+        entry = audit.last_entry(db.connection)
+        assert entry is not None and entry.ts == "2026-01-02T03:04:05.678Z"
+
+
+def test_scalar_and_list_payloads_roundtrip(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        with db.transaction() as conn:
+            audit.record(
+                conn,
+                actor="system",
+                action="apply",
+                entity=Entity.APPLY.value,
+                old_value=["a", "b"],
+                new_value="plain",
+                status=AUDIT_STATUS_FAILED,
+                detail="iptables: exit 4",
+            )
+        entry = audit.last_entry(db.connection)
+        assert entry is not None
+        assert entry.old_value == ["a", "b"]
+        assert entry.new_value == "plain"
+        assert entry.status == AUDIT_STATUS_FAILED
+        assert entry.detail == "iptables: exit 4"
+
+
+def test_no_audit_row_when_transaction_rolls_back(tmp_path: Path) -> None:
+    """Мутация и её аудит коммитятся вместе: откат транзакции не оставляет следа."""
+    with make_db(tmp_path) as db:
+        with pytest.raises(RuntimeError), db.transaction() as conn:
+            audit.record(conn, actor="system", action="update", entity=Entity.RULE.value)
+            raise RuntimeError("мутация не удалась")
+        assert audit.count(db.connection) == 0
+
+
+def test_last_entry_returns_none_on_empty_log(tmp_path: Path) -> None:
+    with make_db(tmp_path) as db:
+        assert audit.last_entry(db.connection) is None
+        assert audit.list_entries(db.connection) == []

backend/tests/test_store_concurrency.py

@@ -0,0 +1,308 @@
+"""Тесты потокобезопасности слоя хранения (#54, D-1/D-2 из #55; issue #20).
+
+Контракт (задокументирован в ``backend/awg_api/store/README.md``): одно
+соединение SQLite, все операции — чтения и записи — сериализуются одним
+``RLock``. Читатель никогда не видит незафиксированных строк и состояния,
+которое затем будет откачено, а конкурентные мутации дают согласованный
+журнал аудита.
+"""
+
+from __future__ import annotations
+
+import asyncio
+import threading
+import time
+from collections.abc import Mapping
+from pathlib import Path
+from typing import Any
+
+import pytest
+
+from awg_api.store import (
+    AUDIT_STATUS_FAILED,
+    ApplyEngine,
+    ApplyError,
+    Database,
+    DesiredState,
+    Entity,
+    Mode,
+    Rule,
+    Store,
+    capture_state,
+)
+
+THREADS = 4
+PER_THREAD = 25
+JOIN_TIMEOUT = 30.0
+# окно наблюдения: за это время незаблокированное чтение гарантированно успело бы вернуться
+OBSERVE_SECONDS = 0.2
+
+RULE_INSERT = (
+    "INSERT INTO routing_rules (name, kind, match, target, priority, enabled,"
+    " created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?, ?)"
+)
+
+
+def open_store(tmp_path: Path) -> tuple[Database, Store]:
+    db = Database(tmp_path / "data" / "awg-dash.db")
+    return db, Store(db)
+
+
+def rule(tid: int, idx: int) -> Rule:
+    return Rule(
+        name=f"r{tid}x{idx}",
+        kind="domain",
+        match=f"t{tid}r{idx}.example.com",
+        target="tun0",
+    )
+
+
+def run_threads(workers: list[Any]) -> list[threading.Thread]:
+    threads = [threading.Thread(target=worker) for worker in workers]
+    for thread in threads:
+        thread.start()
+    for thread in threads:
+        thread.join(JOIN_TIMEOUT)
+        assert not thread.is_alive(), f"поток {thread.name} не завершился"
+    return threads
+
+
+# -- #54: конкурентные мутации вместе с чтениями ---------------------------------
+def test_concurrent_upserts_and_reads_are_consistent(tmp_path: Path) -> None:
+    """N потоков × M upsert с чтениями: без ошибок, rules == audit == N*M."""
+    db, store = open_store(tmp_path)
+    with db:
+        errors: list[str] = []
+        barrier = threading.Barrier(THREADS)
+
+        def worker(tid: int) -> None:
+            try:
+                barrier.wait(timeout=JOIN_TIMEOUT)
+                for idx in range(PER_THREAD):
+                    store.upsert_rule(rule(tid, idx), actor=f"thread{tid}")
+                    store.list_rules()
+                    store.get_mode()
+                    store.get_rule_by_name(f"r{tid}x{idx}")
+            except BaseException as exc:  # noqa: BLE001 - фиксируем любое падение потока
+                errors.append(f"thread{tid}: {type(exc).__name__}: {exc}")
+
+        run_threads([lambda tid=tid: worker(tid) for tid in range(THREADS)])
+
+        total = THREADS * PER_THREAD
+        assert errors == []
+        assert store.counts()["rules"] == total
+        assert store.counts()["audit"] == total
+        assert len(store.list_rules()) == total
+        assert len(store.list_audit(limit=total * 2)) == total
+
+
+# -- #54: чтение не видит незафиксированных строк -------------------------------
+def test_reads_never_see_uncommitted_rows(tmp_path: Path) -> None:
+    """Пока транзакция другого потока открыта, читатель ждёт коммита, а не читает грязь."""
+    db, store = open_store(tmp_path)
+    with db:
+        store.upsert_rule(
+            Rule(name="baseline", kind="domain", match="baseline.example.com", target="tun0"),
+            actor="system",
+        )
+        transaction_open = threading.Event()
+        reader_started = threading.Event()
+        release = threading.Event()
+        observed: list[list[str]] = []
+        writer_errors: list[str] = []
+
+        def writer() -> None:
+            try:
+                with db.transaction() as conn:
+                    conn.execute(
+                        RULE_INSERT,
+                        (
+                            "uncommitted",
+                            "domain",
+                            "uncommitted.example.com",
+                            "tun0",
+                            100,
+                            1,
+                            "2026-01-01T00:00:00Z",
+                            "2026-01-01T00:00:00Z",
+                        ),
+                    )
+                    transaction_open.set()
+                    release.wait(JOIN_TIMEOUT)
+            except BaseException as exc:  # noqa: BLE001 - фиксируем падение писателя
+                writer_errors.append(f"{type(exc).__name__}: {exc}")
+
+        def reader() -> None:
+            reader_started.set()
+            observed.append([item.name for item in store.list_rules()])
+
+        writer_thread = threading.Thread(target=writer)
+        writer_thread.start()
+        assert transaction_open.wait(JOIN_TIMEOUT)
+        reader_thread = threading.Thread(target=reader)
+        reader_thread.start()
+        assert reader_started.wait(JOIN_TIMEOUT)
+        time.sleep(OBSERVE_SECONDS)
+        # незафиксированная строка наружу не видна: чтение ждёт завершения транзакции
+        assert observed == []
+
+        release.set()
+        writer_thread.join(JOIN_TIMEOUT)
+        reader_thread.join(JOIN_TIMEOUT)
+        assert writer_errors == []
+        assert observed == [["baseline", "uncommitted"]]
+
+
+# -- #54 п.4: во время падающего apply наружу не отдаётся откаченное состояние ----
+class BlockingApplier:
+    """Применитель, который «висит» внутри apply и затем падает как iptables."""
+
+    def __init__(self) -> None:
+        self.entered = threading.Event()
+        self.release = threading.Event()
+        self.reverted: list[dict[str, Any]] = []
+
+    def apply(self, payload: Mapping[str, Any]) -> None:
+        self.entered.set()
+        assert self.release.wait(JOIN_TIMEOUT)
+        raise RuntimeError("mock iptables: exit 4")
+
+    def revert(self, payload: Mapping[str, Any]) -> None:
+        self.reverted.append(dict(payload))
+
+
+def test_read_during_failing_apply_never_sees_discarded_state(tmp_path: Path) -> None:
+    """AC #20: снаружи не видно «полуприменённой» конфигурации, которую затем откатят."""
+    db, store = open_store(tmp_path)
+    applier = BlockingApplier()
+    engine = ApplyEngine(store, applier, actor="ui:admin")
+    with db:
+        store.upsert_rule(
+            Rule(name="keep", kind="domain", match="keep.example.com", target="tun0"),
+            actor="system",
+        )
+        before = capture_state(db.connection)
+        plan = engine.stage(
+            DesiredState(
+                mode=Mode.FULL,
+                rules=(Rule(name="new", kind="domain", match="new.example.com", target="tun0"),),
+            ),
+            reason="сломается",
+        )
+        errors: list[BaseException] = []
+        observed: list[list[str]] = []
+        reader_started = threading.Event()
+
+        def apply_worker() -> None:
+            try:
+                engine.apply(plan)
+            except BaseException as exc:  # noqa: BLE001 - ожидаем ApplyError
+                errors.append(exc)
+
+        def reader() -> None:
+            reader_started.set()
+            observed.append([item.name for item in store.list_rules()])
+
+        apply_thread = threading.Thread(target=apply_worker)
+        apply_thread.start()
+        assert applier.entered.wait(JOIN_TIMEOUT)
+        reader_thread = threading.Thread(target=reader)
+        reader_thread.start()
+        assert reader_started.wait(JOIN_TIMEOUT)
+        time.sleep(OBSERVE_SECONDS)
+        assert observed == [], "чтение вернуло состояние, которого ещё нет в БД"
+
+        applier.release.set()
+        apply_thread.join(JOIN_TIMEOUT)
+        reader_thread.join(JOIN_TIMEOUT)
+
+        assert len(errors) == 1
+        error = errors[0]
+        assert isinstance(error, ApplyError)
+        assert error.restored is True
+        assert observed == [["keep"]]
+        assert [item.name for item in store.list_rules()] == ["keep"]
+        assert capture_state(db.connection) == before
+        assert applier.reverted == [before]
+
+
+# -- #55 D-1: BaseException не должен оставлять staged без исхода ---------------
+class InterruptingApplier:
+    """Применитель, прерывающий apply исключением из ``BaseException``."""
+
+    def __init__(self, exc_type: type[BaseException]) -> None:
+        self.exc_type = exc_type
+        self.applied = 0
+        self.reverted: list[dict[str, Any]] = []
+
+    def apply(self, payload: Mapping[str, Any]) -> None:
+        self.applied += 1
+        raise self.exc_type("внешний применитель прерван")
+
+    def revert(self, payload: Mapping[str, Any]) -> None:
+        self.reverted.append(dict(payload))
+
+
+@pytest.mark.parametrize("exc_type", [KeyboardInterrupt, SystemExit, asyncio.CancelledError])
+def test_base_exception_from_applier_reverts_and_records_failure(
+    tmp_path: Path, exc_type: type[BaseException]
+) -> None:
+    """Отмена/прерывание apply → revert внешней подсистемы + failed в audit_log."""
+    db, store = open_store(tmp_path)
+    applier = InterruptingApplier(exc_type)
+    engine = ApplyEngine(store, applier, actor="ui:admin")
+    with db:
+        store.upsert_rule(
+            Rule(name="keep", kind="domain", match="keep.example.com", target="tun0"),
+            actor="system",
+        )
+        before = capture_state(db.connection)
+        plan = engine.stage(
+            DesiredState(
+                mode=Mode.FULL,
+                rules=(Rule(name="new", kind="domain", match="new.example.com", target="tun0"),),
+            ),
+            reason="отмена",
+        )
+
+        with pytest.raises(exc_type):
+            engine.apply(plan)
+
+        assert applier.applied == 1
+        assert applier.reverted == [before]
+        assert capture_state(db.connection) == before
+        assert [item.name for item in store.list_rules()] == ["keep"]
+
+        entries = store.list_audit(entity=Entity.APPLY.value, entity_id=plan.plan_id, limit=10)
+        assert entries[0].status == AUDIT_STATUS_FAILED
+        assert exc_type.__name__ in (entries[0].detail or "")
+        assert entries[0].new_value == before
+
+
+# -- #55 D-2: конкурентные set_geoip_schedule дают связный журнал ---------------
+def test_concurrent_geoip_updates_keep_audit_chain_consistent(tmp_path: Path) -> None:
+    """Каждое изменение пишет корректный old_value: цепочка old→new не рвётся."""
+    db, store = open_store(tmp_path)
+    with db:
+        initial = store.get_geoip_schedule()
+        crons = ("0 1 * * *", "0 2 * * *")
+        errors: list[str] = []
+        barrier = threading.Barrier(len(crons))
+
+        def worker(cron: str) -> None:
+            try:
+                barrier.wait(timeout=JOIN_TIMEOUT)
+                store.set_geoip_schedule(cron=cron, actor=f"ui:{cron}")
+            except BaseException as exc:  # noqa: BLE001 - фиксируем падение потока
+                errors.append(f"{cron}: {type(exc).__name__}: {exc}")
+
+        run_threads([lambda cron=cron: worker(cron) for cron in crons])
+
+        assert errors == []
+        entries = list(reversed(store.list_audit(entity=Entity.GEOIP_SCHEDULE.value, limit=10)))
+        assert len(entries) == len(crons)
+        first, second = entries
+        assert first.old_value["cron"] == initial.cron
+        assert first.new_value["cron"] == second.old_value["cron"]
+        assert second.new_value["cron"] == store.get_geoip_schedule().cron
+        assert {first.new_value["cron"], second.new_value["cron"]} == set(crons)

backend/tests/test_store_migrations.py

@@ -0,0 +1,153 @@
+"""Тесты схемы, миграций и проверки версии при старте (issue #20)."""
+
+from __future__ import annotations
+
+import sqlite3
+from pathlib import Path
+
+import pytest
+
+from awg_api.store import (
+    EXPECTED_TABLES,
+    LATEST_VERSION,
+    MIGRATIONS,
+    Database,
+    Migration,
+    SchemaError,
+    StorageError,
+    current_version,
+    migrate,
+    resolve_db_path,
+    verify_schema,
+)
+from awg_api.store.migrations import applied_migrations, table_columns, table_names
+
+
+def test_empty_data_dir_creates_schema(tmp_path: Path) -> None:
+    """GIVEN пустой /data, WHEN старт, THEN схема v1 создана автоматически."""
+    db_path = tmp_path / "data" / "awg-dash.db"
+    assert not db_path.parent.exists()
+
+    with Database(db_path) as db:
+        assert db.schema_version == LATEST_VERSION == 1
+        assert db.migration_report is not None
+        assert db.migration_report.applied == (1,)
+        names = table_names(db.connection)
+        assert set(EXPECTED_TABLES) <= names
+        for table, columns in EXPECTED_TABLES.items():
+            assert columns <= table_columns(db.connection, table), table
+
+
+def test_wal_mode_is_enabled(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        assert db.journal_mode.lower() == "wal"
+        assert db.is_wal is True
+
+
+def test_seed_rows_present(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        row = db.connection.execute("SELECT mode FROM routing_mode WHERE id = 1").fetchone()
+        assert row is not None and row["mode"] == "off"
+        geoip = db.connection.execute("SELECT cron, provider FROM geoip_schedule WHERE id = 1").fetchone()
+        assert geoip is not None
+        assert geoip["provider"] == "ripe"
+
+
+def test_migrate_is_idempotent(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        report = db.migrate()
+        assert report.applied == ()
+        assert report.changed is False
+        assert report.from_version == report.to_version == LATEST_VERSION
+
+
+def test_applied_migrations_map(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        assert applied_migrations(db.connection) == {1: "initial-state-schema"}
+
+
+def test_auto_migrate_false_verifies_existing_schema(tmp_path: Path) -> None:
+    path = tmp_path / "awg-dash.db"
+    with Database(path):
+        pass
+    with Database(path, auto_migrate=False) as db:
+        assert db.migration_report is None
+        assert current_version(db.connection) == LATEST_VERSION
+
+
+def test_auto_migrate_false_on_unmigrated_db_raises(tmp_path: Path) -> None:
+    conn = sqlite3.connect(str(tmp_path / "empty.db"))
+    try:
+        with pytest.raises(SchemaError, match="не мигрирована"):
+            verify_schema(conn)
+    finally:
+        conn.close()
+
+
+def test_verify_schema_detects_missing_table(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        db.connection.execute("DROP TABLE routing_rules")
+        with pytest.raises(SchemaError, match="routing_rules"):
+            db.verify_schema()
+
+
+def test_verify_schema_detects_missing_column(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        db.connection.execute("ALTER TABLE devices DROP COLUMN address")
+        with pytest.raises(SchemaError, match="address"):
+            db.verify_schema()
+
+
+def test_verify_schema_rejects_newer_schema(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        db.connection.execute(
+            "INSERT INTO schema_migrations (version, name, applied_at) VALUES (?, ?, ?)",
+            (99, "from-the-future", "2099-01-01T00:00:00.000Z"),
+        )
+        with pytest.raises(SchemaError, match="новее"):
+            db.verify_schema()
+        with pytest.raises(SchemaError, match="новее"):
+            db.migrate()
+
+
+def test_failed_migration_leaves_schema_untouched(tmp_path: Path) -> None:
+    broken = MIGRATIONS + (
+        Migration(version=2, name="broken", statements=("CREATE TABLE t2 (id INTEGER)", "NOT SQL AT ALL")),
+    )
+    with Database(tmp_path / "awg-dash.db") as db:
+        with pytest.raises(StorageError, match="миграция v2"):
+            migrate(db.connection, migrations=broken)
+        assert current_version(db.connection) == 1
+        assert "t2" not in table_names(db.connection)
+
+
+def test_migrate_rejects_downgrade(tmp_path: Path) -> None:
+    with Database(tmp_path / "awg-dash.db") as db:
+        db.connection.execute(
+            "INSERT INTO schema_migrations (version, name, applied_at) VALUES (?, ?, ?)",
+            (2, "newer", "2099-01-01T00:00:00.000Z"),
+        )
+        with pytest.raises(SchemaError, match="новее"):
+            migrate(db.connection, migrations=MIGRATIONS)
+
+
+def test_resolve_db_path_defaults_and_env(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.delenv("AWG_DASH_DB", raising=False)
+    assert resolve_db_path() == Path("/data/awg-dash.db")
+    monkeypatch.setenv("AWG_DASH_DB", str(tmp_path / "custom.db"))
+    assert resolve_db_path() == tmp_path / "custom.db"
+    assert resolve_db_path(tmp_path / "explicit.db") == tmp_path / "explicit.db"
+
+
+def test_database_uses_env_path(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> None:
+    monkeypatch.setenv("AWG_DASH_DB", str(tmp_path / "nested" / "env.db"))
+    with Database() as db:
+        assert db.path == tmp_path / "nested" / "env.db"
+        assert db.path.exists()
+
+
+def test_unwritable_path_raises_storage_error(tmp_path: Path) -> None:
+    blocker = tmp_path / "blocked"
+    blocker.write_text("not a directory")
+    with pytest.raises(StorageError, match="каталог"):
+        Database(blocker / "awg-dash.db")

backend/tests/test_store_persistence.py

@@ -0,0 +1,184 @@
+"""Персистентность: рестарт «контейнера» сохраняет правила, конфиг и аудит (issue #20)."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from awg_api.store import (
+    ConfigMeta,
+    Database,
+    DesiredState,
+    Device,
+    GeoIpSchedule,
+    Mode,
+    Rule,
+    StorageError,
+    Store,
+    ValidationError,
+    open_storage,
+    rollback_to,
+)
+from awg_api.store import validation
+
+
+def test_state_survives_container_restart(tmp_path: Path) -> None:
+    """GIVEN рестарт контейнера, WHEN он завершён, THEN правила и конфиг на месте."""
+    db_path = tmp_path / "data" / "awg-dash.db"
+
+    with Database(db_path) as first:
+        store = Store(first)
+        store.set_mode(Mode.SPLIT, actor="ui:admin")
+        store.set_geoip_schedule(cron="0 3 * * *", actor="ui:admin")
+        store.upsert_rule(
+            Rule(name="yt", kind="domain", match="youtube.com", target="tun0", priority=10),
+            actor="ui:admin",
+        )
+        store.upsert_rule(
+            Rule(name="lan", kind="cidr", match="10.0.0.0/8", target="direct", priority=200),
+            actor="ui:admin",
+        )
+        store.upsert_config(
+            ConfigMeta(name="peer1", path="/config/peer1.conf", checksum="deadbeef", size_bytes=1024),
+            actor="ui:admin",
+        )
+        store.register_device(Device(mac="aa:bb:cc:dd:ee:ff", name="notebook"), actor="ui:admin")
+        audit_before = store.counts()["audit"]
+        assert audit_before == 6
+
+    # «рестарт контейнера»: новое соединение к тому же /data
+    with Database(db_path) as second:
+        store = Store(second)
+        assert second.is_wal is True
+        assert store.get_mode() == Mode.SPLIT
+        assert store.get_geoip_schedule().cron == "0 3 * * *"
+        assert [(rule.name, rule.target) for rule in store.list_rules()] == [
+            ("yt", "tun0"),
+            ("lan", "direct"),
+        ]
+        config = store.get_config("peer1")
+        assert config is not None
+        assert config.checksum == "deadbeef"
+        assert store.get_device("aa:bb:cc:dd:ee:ff") is not None
+        assert store.counts()["audit"] == audit_before
+        assert second.migration_report is not None  # миграции уже применены, повтор не нужен
+        assert second.migration_report.applied == ()
+
+
+def test_wal_file_next_to_database(tmp_path: Path) -> None:
+    db_path = tmp_path / "data" / "awg-dash.db"
+    with Database(db_path) as db:
+        Store(db).set_mode(Mode.FULL, actor="system")
+        assert db_path.with_name("awg-dash.db-wal").exists()
+        assert db_path.with_name("awg-dash.db-shm").exists()
+
+
+def test_open_storage_builds_full_stack(tmp_path: Path) -> None:
+    with open_storage(tmp_path / "data" / "awg-dash.db", actor="api:token") as storage:
+        storage.store.set_mode(Mode.SPLIT, actor="api:token")
+        plan = storage.engine.stage(
+            DesiredState(mode=Mode.SPLIT, rules=(), geoip=GeoIpSchedule()),
+            reason="через storage",
+        )
+        result = storage.engine.apply(plan)
+        assert result.ok is True
+        assert storage.store.counts()["snapshots"] == 1
+        assert storage.db.schema_version == 1
+
+
+def test_rollback_helper_and_missing_snapshot(tmp_path: Path) -> None:
+    with open_storage(tmp_path / "data" / "awg-dash.db") as storage:
+        storage.store.set_mode(Mode.OFF, actor="system")
+        plan = storage.engine.stage(DesiredState(mode=Mode.FULL))
+        storage.engine.apply(plan)
+        assert storage.store.get_mode() == Mode.FULL
+
+        snapshot = rollback_to(storage.engine, plan.plan_id, reason="ручной откат")
+        assert snapshot.payload["mode"] == "off"
+        assert storage.store.get_mode() == Mode.OFF
+
+        with pytest.raises(StorageError, match="не найден"):
+            storage.engine.rollback(999999)
+
+
+def test_transactions_are_isolated_per_connection(tmp_path: Path) -> None:
+    db_path = tmp_path / "data" / "awg-dash.db"
+    with Database(db_path) as writer, Database(db_path) as reader:
+        Store(writer).set_mode(Mode.SPLIT, actor="system")
+        assert Store(reader).get_mode() == Mode.SPLIT
+        with pytest.raises(RuntimeError, match="откат"), writer.transaction() as conn:
+            conn.execute("UPDATE routing_mode SET mode = 'full' WHERE id = 1")
+            raise RuntimeError("откат")
+        assert Store(reader).get_mode() == Mode.SPLIT
+
+
+# -- валидация (чистые функции) -------------------------------------------------
+@pytest.mark.parametrize(
+    ("raw", "expected"),
+    [
+        ("AA:BB:CC:DD:EE:FF", "aa:bb:cc:dd:ee:ff"),
+        ("aa-bb-cc-dd-ee-ff", "aa:bb:cc:dd:ee:ff"),
+        ("aabbccddeeff", "aa:bb:cc:dd:ee:ff"),
+    ],
+)
+def test_normalize_mac(raw: str, expected: str) -> None:
+    assert validation.normalize_mac(raw) == expected
+
+
+def test_normalize_mac_rejects_garbage() -> None:
+    with pytest.raises(ValidationError, match="MAC"):
+        validation.normalize_mac("not-a-mac")
+
+
+@pytest.mark.parametrize("value", ["ok", "peer_1", "rule-2", "a.b:c"])
+def test_validate_name_accepts(value: str) -> None:
+    assert validation.validate_name("name", f"  {value}  ") == value
+
+
+@pytest.mark.parametrize("value", ["", "UPPER", "-lead", "with space", "юникод", "x" * 64])
+def test_validate_name_rejects(value: str) -> None:
+    with pytest.raises(ValidationError):
+        validation.validate_name("name", value)
+
+
+@pytest.mark.parametrize("value", ["/config/peer1.conf", "/etc/awg-dash/rules.conf"])
+def test_validate_config_path_accepts(value: str) -> None:
+    assert validation.validate_config_path(value) == value
+
+
+@pytest.mark.parametrize("value", ["relative.conf", "/config/../../etc/shadow", ""])
+def test_validate_config_path_rejects(value: str) -> None:
+    with pytest.raises(ValidationError):
+        validation.validate_config_path(value)
+
+
+@pytest.mark.parametrize(("value", "expected"), [("RIPE", "ripe"), ("maxmind", "maxmind")])
+def test_validate_provider(value: str, expected: str) -> None:
+    assert validation.validate_provider(value) == expected
+
+
+@pytest.mark.parametrize("value", ["tunnel", "direct", "block", "default"])
+def test_validate_device_policy_accepts(value: str) -> None:
+    assert validation.validate_device_policy(value) == value
+
+
+def test_validate_device_policy_rejects() -> None:
+    with pytest.raises(ValidationError, match="policy"):
+        validation.validate_device_policy("root")
+
+
+@pytest.mark.parametrize("value", ["*.example.com", "youtube.com", "a.b.c.example.co.uk"])
+def test_validate_match_domain(value: str) -> None:
+    assert validation.validate_match("domain", value) == value
+
+
+@pytest.mark.parametrize("value", ["10.0.0.0/8", "2001:db8::/32", "192.168.1.7"])
+def test_validate_match_cidr(value: str) -> None:
+    assert validation.validate_match("cidr", value) == value
+
+
+def test_validate_match_ipset_and_empty() -> None:
+    assert validation.validate_match("ipset", "awg_ru") == "awg_ru"
+    with pytest.raises(ValidationError, match="пустым"):
+        validation.validate_match("domain", "   ")

backend/tests/test_store_repository.py

@@ -0,0 +1,312 @@
+"""Тесты репозитория: CRUD-мутации с аудитом «old→new» (issue #20)."""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+import pytest
+
+from awg_api.store import (
+    ConfigMeta,
+    Database,
+    Device,
+    Entity,
+    GeoIpSchedule,
+    Mode,
+    Rule,
+    RuleException,
+    StorageError,
+    Store,
+    ValidationError,
+)
+from awg_api.store import audit
+from awg_api.store.validation import validate_priority
+
+
+def make_store(tmp_path: Path) -> tuple[Database, Store]:
+    db = Database(tmp_path / "data" / "awg-dash.db")
+    return db, Store(db)
+
+
+# -- правила -----------------------------------------------------------------
+def test_upsert_rule_creates_with_audit(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        saved = store.upsert_rule(
+            Rule(name="yt", kind="domain", match="youtube.com", target="tun0", priority=10),
+            actor="ui:admin",
+        )
+        assert saved.id is not None and saved.created_at == saved.updated_at
+        assert store.get_rule(saved.id) == saved
+        assert store.get_rule_by_name("yt") == saved
+        entries = store.list_audit(entity=Entity.RULE.value)
+        assert len(entries) == 1
+        assert entries[0].action == "create"
+        assert entries[0].old_value is None
+        assert entries[0].new_value is not None
+        assert entries[0].new_value["name"] == "yt"
+
+
+def test_upsert_rule_updates_by_name_and_records_old_new(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        first = store.upsert_rule(Rule(name="yt", kind="domain", match="youtube.com", target="tun0"),
+                                  actor="ui:admin")
+        second = store.upsert_rule(Rule(name="yt", kind="domain", match="youtu.be", target="tun1"),
+                                   actor="ui:admin")
+        assert second.id == first.id
+        assert second.match == "youtu.be" and second.target == "tun1"
+        assert store.counts()["rules"] == 1
+        entries = store.list_audit(entity=Entity.RULE.value)
+        assert [entry.action for entry in entries] == ["update", "create"]
+        assert entries[0].old_value["match"] == "youtube.com"
+        assert entries[0].new_value["match"] == "youtu.be"
+        assert entries[0].old_value["target"] == "tun0"
+        assert entries[0].new_value["target"] == "tun1"
+
+
+def test_upsert_rule_by_id(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        saved = store.upsert_rule(Rule(name="a", kind="cidr", match="10.0.0.0/8", target="tun0"),
+                                  actor="system")
+        updated = store.upsert_rule(
+            Rule(id=saved.id, name="a", kind="cidr", match="10.1.0.0/16", target="tun0", enabled=False),
+            actor="system",
+        )
+        assert updated.id == saved.id
+        assert updated.match == "10.1.0.0/16"
+        assert updated.enabled is False
+        assert store.list_rules(enabled_only=True) == []
+
+
+def test_rule_validation_rejects_bad_input(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        cases = [
+            Rule(name="Bad Name", kind="domain", match="youtube.com", target="tun0"),
+            Rule(name="ok", kind="wrong", match="youtube.com", target="tun0"),
+            Rule(name="ok2", kind="domain", match="not a domain", target="tun0"),
+            Rule(name="ok3", kind="cidr", match="10.0.0.0/99", target="tun0"),
+            Rule(name="ok4", kind="domain", match="youtube.com", target="bad target!"),
+            Rule(name="ok5", kind="domain", match="youtube.com", target="tun0", priority=-1),
+        ]
+        for rule in cases:
+            with pytest.raises(ValidationError):
+                store.upsert_rule(rule, actor="system")
+        assert store.counts()["rules"] == 0
+        assert audit.count(db.connection) == 0
+
+
+def test_priority_must_be_int() -> None:
+    with pytest.raises(ValidationError, match="целое"):
+        validate_priority(True)  # bool не является допустимым приоритетом
+    with pytest.raises(ValidationError, match="диапазона"):
+        validate_priority(70000)
+
+
+def test_delete_rule(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        saved = store.upsert_rule(Rule(name="yt", kind="domain", match="youtube.com", target="tun0"),
+                                  actor="ui:admin")
+        assert saved.id is not None
+        assert store.delete_rule(saved.id, actor="ui:admin") is True
+        assert store.delete_rule(saved.id, actor="ui:admin") is False
+        assert store.get_rule(saved.id) is None
+        entries = store.list_audit(entity=Entity.RULE.value)
+        assert [entry.action for entry in entries] == ["delete", "create"]
+        assert entries[0].new_value is None
+        assert entries[0].old_value["name"] == "yt"
+
+
+def test_rules_sorted_by_priority(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        store.upsert_rule(Rule(name="b", kind="domain", match="b.example.com", target="tun0",
+                               priority=200), actor="system")
+        store.upsert_rule(Rule(name="a", kind="domain", match="a.example.com", target="tun0",
+                               priority=5), actor="system")
+        assert [rule.name for rule in store.list_rules()] == ["a", "b"]
+
+
+# -- исключения ---------------------------------------------------------------
+def test_exception_upsert_update_delete(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        created = store.upsert_exception(RuleException(match="bank.example.com", reason="банк"),
+                                        actor="ui:admin")
+        assert created.id is not None
+        assert store.get_exception("bank.example.com") == created
+
+        updated = store.upsert_exception(RuleException(match="bank.example.com", reason="банк2"),
+                                         actor="ui:admin")
+        assert updated.id == created.id and updated.reason == "банк2"
+        assert store.counts()["exceptions"] == 1
+
+        assert store.list_exceptions() == [updated]
+        assert store.delete_exception(updated.id or 0, actor="ui:admin") is True
+        assert store.delete_exception(updated.id or 0, actor="ui:admin") is False
+
+        actions = [entry.action for entry in store.list_audit(entity=Entity.EXCEPTION.value)]
+        assert actions == ["delete", "update", "create"]
+        update_entry = store.list_audit(entity=Entity.EXCEPTION.value)[1]
+        assert update_entry.old_value["reason"] == "банк"
+        assert update_entry.new_value["reason"] == "банк2"
+
+
+def test_exception_accepts_cidr_and_rejects_garbage(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        assert store.upsert_exception(RuleException(match="192.168.1.0/24"), actor="system").match == (
+            "192.168.1.0/24"
+        )
+        assert store.upsert_exception(RuleException(match="10.0.0.1"), actor="system").match == "10.0.0.1"
+        with pytest.raises(ValidationError, match="домен"):
+            store.upsert_exception(RuleException(match="!!!"), actor="system")
+        with pytest.raises(ValidationError, match="пустым"):
+            store.upsert_exception(RuleException(match="  "), actor="system")
+
+
+# -- режим и GeoIP -------------------------------------------------------------
+def test_set_mode_defaults_off_and_audits(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        assert store.get_mode() == Mode.OFF
+        assert store.set_mode("split", actor="ui:admin") == Mode.SPLIT
+        assert store.get_mode() == Mode.SPLIT
+        assert store.set_mode(Mode("full"), actor="ui:admin") == Mode.FULL
+        entries = store.list_audit(entity=Entity.MODE.value)
+        assert len(entries) == 2
+        assert entries[0].old_value == {"mode": "split"}
+        assert entries[0].new_value == {"mode": "full"}
+        assert entries[0].actor == "ui:admin"
+
+
+def test_set_mode_rejects_unknown(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        with pytest.raises(ValidationError, match="mode"):
+            store.set_mode("turbo", actor="ui:admin")
+        assert store.get_mode() == Mode.OFF
+
+
+def test_geoip_schedule_defaults_and_partial_update(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        default = store.get_geoip_schedule()
+        assert default == GeoIpSchedule(enabled=True, cron="0 4 * * *", provider="ripe",
+                                        updated_at=default.updated_at)
+        updated = store.set_geoip_schedule(cron="*/30 * * * *", actor="ui:admin")
+        assert updated.cron == "*/30 * * * *"
+        assert updated.provider == "ripe" and updated.enabled is True
+
+        disabled = store.set_geoip_schedule(enabled=False, provider="MAXMIND", actor="ui:admin")
+        assert disabled.enabled is False and disabled.provider == "maxmind"
+        assert store.get_geoip_schedule() == disabled
+
+        with pytest.raises(ValidationError, match="cron"):
+            store.set_geoip_schedule(cron="ежечасно", actor="ui:admin")
+        with pytest.raises(ValidationError, match="provider"):
+            store.set_geoip_schedule(provider="!", actor="ui:admin")
+
+        entries = store.list_audit(entity=Entity.GEOIP_SCHEDULE.value)
+        assert [entry.action for entry in entries] == ["set_geoip_schedule"] * 2
+        assert entries[0].old_value["provider"] == "ripe"
+        assert entries[0].new_value["provider"] == "maxmind"
+
+
+# -- конфиги ------------------------------------------------------------------
+def test_config_upsert_and_mark_applied(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        created = store.upsert_config(
+            ConfigMeta(name="client-peer1", path="/config/peer1.conf", version=1, checksum="abc",
+                       size_bytes=512), actor="ui:admin",
+        )
+        assert created.id is not None
+        assert store.get_config("client-peer1") == created
+
+        updated = store.upsert_config(
+            ConfigMeta(name="client-peer1", path="/config/peer1.conf", version=2, checksum="def",
+                       size_bytes=640, applied=True), actor="ui:admin",
+        )
+        assert updated.version == 2 and updated.applied is True
+        assert store.counts()["configs"] == 1
+
+        marked = store.mark_config_applied("client-peer1", applied=False, actor="ui:admin")
+        assert marked.applied is False
+
+        entries = store.list_audit(entity=Entity.CONFIG.value)
+        assert [entry.action for entry in entries] == ["set_applied", "update", "create"]
+        assert entries[0].old_value["applied"] is True
+        assert entries[0].new_value["applied"] is False
+        assert entries[1].old_value["version"] == 1
+        assert entries[1].new_value["version"] == 2
+
+
+def test_config_validation_and_missing(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        with pytest.raises(ValidationError, match="path"):
+            store.upsert_config(ConfigMeta(name="x", path="relative.conf"), actor="system")
+        with pytest.raises(ValidationError, match="path"):
+            store.upsert_config(ConfigMeta(name="x", path="/config/../etc/passwd"), actor="system")
+        with pytest.raises(ValidationError, match="name"):
+            store.upsert_config(ConfigMeta(name="Bad Name", path="/config/x.conf"), actor="system")
+        with pytest.raises(StorageError, match="не найден"):
+            store.mark_config_applied("ghost", applied=True, actor="system")
+
+
+# -- устройства -----------------------------------------------------------------
+def test_device_register_normalizes_mac_and_audits(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        created = store.register_device(
+            Device(mac="AA-BB-CC-DD-EE-FF", name="notebook", address="192.168.1.50"),
+            actor="ui:admin",
+        )
+        assert created.mac == "aa:bb:cc:dd:ee:ff"
+        assert store.get_device("AA:BB:CC:DD:EE:FF") == created
+
+        updated = store.register_device(
+            Device(mac="aabbccddeeff", name="notebook", policy="direct", last_seen="2026-01-01T00:00:00.000Z"),
+            actor="ui:admin",
+        )
+        assert updated.id == created.id and updated.policy == "direct"
+        assert store.counts()["devices"] == 1
+
+        assert store.delete_device("aa:bb:cc:dd:ee:ff", actor="ui:admin") is True
+        assert store.delete_device("aa:bb:cc:dd:ee:ff", actor="ui:admin") is False
+        assert store.list_devices() == []
+
+        actions = [entry.action for entry in store.list_audit(entity=Entity.DEVICE.value)]
+        assert actions == ["delete", "update", "create"]
+        update_entry = store.list_audit(entity=Entity.DEVICE.value)[1]
+        assert update_entry.old_value["policy"] == "default"
+        assert update_entry.new_value["policy"] == "direct"
+
+
+def test_device_validation(tmp_path: Path) -> None:
+    db, store = make_store(tmp_path)
+    with db:
+        with pytest.raises(ValidationError, match="MAC"):
+            store.register_device(Device(mac="zz:zz", name="x"), actor="system")
+        with pytest.raises(ValidationError, match="policy"):
+            store.register_device(Device(mac="aa:bb:cc:dd:ee:ff", name="x", policy="кибератака"),
+                                  actor="system")
+        with pytest.raises(ValidationError, match="name"):
+            store.register_device(Device(mac="aa:bb:cc:dd:ee:ff", name="Not A Name"), actor="system")
+
+
+def test_audit_actor_recorded_per_mutation(tmp_path: Path) -> None:
+    """GIVEN изменение через сервисный слой, THEN в audit_log есть actor и old/new."""
+    db, store = make_store(tmp_path)
+    with db:
+        store.set_mode(Mode.SPLIT, actor="api:token-42")
+        entry = store.list_audit(entity=Entity.MODE.value)[0]
+        assert entry.actor == "api:token-42"
+        assert entry.ts.endswith("Z")
+        assert entry.old_value == {"mode": "off"}
+        assert entry.new_value == {"mode": "split"}
+        assert entry.status == "ok"