add crud for exchange

backend/trading_journal/crud.py

@@ -245,6 +245,83 @@ def update_cycle(session: Session, cycle_id: int, update_data: Mapping) -> model
     return cycle
 
 
+# Exchanges
+IMMUTABLE_EXCHANGE_FIELDS = {"id"}
+
+
+def create_exchange(session: Session, exchange_data: Mapping) -> models.Exchanges:
+    if hasattr(exchange_data, "dict"):
+        data = exchange_data.dict(exclude_unset=True)
+    else:
+        data = dict(exchange_data)
+    allowed = {c.name for c in models.Exchanges.__table__.columns}
+    payload = {k: v for k, v in data.items() if k in allowed}
+    if "name" not in payload:
+        raise ValueError("name is required")
+
+    e = models.Exchanges(**payload)
+    session.add(e)
+    try:
+        session.flush()
+    except IntegrityError as e:
+        session.rollback()
+        raise ValueError("create_exchange integrity error") from e
+    session.refresh(e)
+    return e
+
+
+def get_exchange_by_id(session: Session, exchange_id: int) -> models.Exchanges | None:
+    return session.get(models.Exchanges, exchange_id)
+
+
+def get_exchange_by_name(session: Session, name: str) -> models.Exchanges | None:
+    statement = select(models.Exchanges).where(
+        models.Exchanges.name == name,
+    )
+    return session.exec(statement).first()
+
+
+def get_all_exchanges(session: Session) -> list[models.Exchanges]:
+    statement = select(models.Exchanges)
+    return session.exec(statement).all()
+
+
+def update_exchange(session: Session, exchange_id: int, update_data: Mapping) -> models.Exchanges:
+    exchange: models.Exchanges | None = session.get(models.Exchanges, exchange_id)
+    if exchange is None:
+        raise ValueError("exchange_id does not exist")
+    if hasattr(update_data, "dict"):
+        data = update_data.dict(exclude_unset=True)
+    else:
+        data = dict(update_data)
+    allowed = {c.name for c in models.Exchanges.__table__.columns}
+    for k, v in data.items():
+        if k in IMMUTABLE_EXCHANGE_FIELDS:
+            raise ValueError(f"field {k!r} is immutable")
+        if k in allowed:
+            setattr(exchange, k, v)
+    session.add(exchange)
+    try:
+        session.flush()
+    except IntegrityError as e:
+        session.rollback()
+        raise ValueError("update_exchange integrity error") from e
+    session.refresh(exchange)
+    return exchange
+
+
+def delete_exchange(session: Session, exchange_id: int) -> None:
+    exchange: models.Exchanges | None = session.get(models.Exchanges, exchange_id)
+    if exchange is None:
+        return
+    session.delete(exchange)
+    try:
+        session.flush()
+    except IntegrityError as e:
+        session.rollback()
+        raise ValueError("delete_exchange integrity error") from e
+
+
 # Users
 IMMUTABLE_USER_FIELDS = {"id", "username", "created_at"}