feat: advanced RW sync system

db/models/__init__.py

@@ -3,6 +3,7 @@ from .invoice import Invoice
 from .link_codes import LinkCode
 from .orders import Order, OrderAddon
 from .pricing import PricingConfig
+from .rw_sync_outbox import RWSyncOutbox
 from .service_notifications import ServiceNotification
 from .service_signatures import ServiceSignature
 from .sessions import Session
@@ -19,6 +20,7 @@ __all__ = [
     "Order",
     "OrderAddon",
     "PricingConfig",
+    "RWSyncOutbox",
     "ServiceNotification",
     "ServiceSignature",
     "Session",

db/models/rw_sync_outbox.py

@@ -0,0 +1,34 @@
+from datetime import UTC, datetime
+from typing import TYPE_CHECKING
+
+from sqlalchemy import INTEGER, DateTime, ForeignKey
+from sqlalchemy.orm import Mapped, mapped_column, relationship
+
+from db.base import Base
+
+if TYPE_CHECKING:
+    from db.models import Subscription
+
+
+class RWSyncOutbox(Base):
+    __tablename__ = "rw_sync_outbox"
+
+    id: Mapped[int] = mapped_column(INTEGER, primary_key=True, autoincrement=True)
+    subscription_id: Mapped[int] = mapped_column(
+        ForeignKey("subscriptions.id"), nullable=False, unique=True
+    )
+    revision: Mapped[int] = mapped_column(INTEGER, nullable=False, default=1)
+    attempts: Mapped[int] = mapped_column(INTEGER, nullable=False, default=0)
+    next_attempt_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)
+    locked_until: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), nullable=False, default=lambda: datetime.now(UTC)
+    )
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True),
+        nullable=False,
+        default=lambda: datetime.now(UTC),
+        onupdate=lambda: datetime.now(UTC),
+    )
+
+    subscription: Mapped["Subscription"] = relationship("Subscription", lazy="selectin")