Refactor code structure for improved readability and maintainability

app/models.py

@@ -0,0 +1,69 @@
+import uuid
+from datetime import datetime
+from decimal import Decimal
+from enum import StrEnum
+from typing import Any
+
+from sqlalchemy import DateTime, Enum, Integer, Numeric, String, Text, func
+from sqlalchemy.dialects.postgresql import JSONB, UUID
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.db import Base
+
+
+class Currency(StrEnum):
+    RUB = "RUB"
+    USD = "USD"
+    EUR = "EUR"
+
+
+class PaymentStatus(StrEnum):
+    PENDING = "pending"
+    SUCCEEDED = "succeeded"
+    FAILED = "failed"
+
+
+class Payment(Base):
+    __tablename__ = "payments"
+
+    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    amount: Mapped[Decimal] = mapped_column(Numeric(18, 2), nullable=False)
+    currency: Mapped[Currency] = mapped_column(
+        Enum(Currency, name="currency", values_callable=lambda values: [v.value for v in values]),
+        nullable=False,
+    )
+    description: Mapped[str] = mapped_column(String(500), nullable=False)
+    metadata_: Mapped[dict[str, Any]] = mapped_column(
+        "metadata", JSONB, default=dict, nullable=False
+    )
+    status: Mapped[PaymentStatus] = mapped_column(
+        Enum(
+            PaymentStatus,
+            name="payment_status",
+            values_callable=lambda values: [v.value for v in values],
+        ),
+        default=PaymentStatus.PENDING,
+        nullable=False,
+    )
+    idempotency_key: Mapped[str] = mapped_column(String(255), unique=True, nullable=False)
+    webhook_url: Mapped[str] = mapped_column(Text, nullable=False)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), nullable=False
+    )
+    processed_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
+    webhook_delivered_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True))
+
+
+class OutboxEvent(Base):
+    __tablename__ = "outbox"
+
+    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    aggregate_id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), nullable=False, index=True)
+    event_type: Mapped[str] = mapped_column(String(100), nullable=False)
+    payload: Mapped[dict[str, Any]] = mapped_column(JSONB, nullable=False)
+    attempts: Mapped[int] = mapped_column(Integer, default=0, nullable=False)
+    last_error: Mapped[str | None] = mapped_column(Text)
+    created_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), nullable=False
+    )
+    published_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), index=True)