Fix pgbouncer relationship

src/api/organization/project/branch/__init__.py

@@ -1766,7 +1766,7 @@ async def update_pgbouncer_config(
     branch: BranchDep,
     parameters: BranchPgbouncerConfigUpdate,
 ) -> BranchPgbouncerConfigStatus:
-    config = await _ensure_pgbouncer_config(session, branch)
+    config = await _ensure_pgbouncer_config(branch)
 
     namespace, vmi_name = get_autoscaler_vm_identity(branch.id)
     host = _pgbouncer_host_for_namespace(namespace)
@@ -2002,20 +2002,10 @@ async def control_branch(
 api.include_router(instance_api)
 
 
-async def _ensure_pgbouncer_config(session: SessionDep, branch: Branch) -> PgbouncerConfig:
-    config = await session.scalar(select(PgbouncerConfig).where(PgbouncerConfig.branch_id == branch.id))
+async def _ensure_pgbouncer_config(branch: Branch) -> PgbouncerConfig:
+    config = await branch.awaitable_attrs.pgbouncer_config
     if config is None:
-        config = PgbouncerConfig(
-            default_pool_size=PgbouncerConfig.DEFAULT_POOL_SIZE,
-            max_client_conn=PgbouncerConfig.DEFAULT_MAX_CLIENT_CONN,
-            query_wait_timeout=PgbouncerConfig.DEFAULT_QUERY_WAIT_TIMEOUT,
-            reserve_pool_size=PgbouncerConfig.DEFAULT_RESERVE_POOL_SIZE,
-            server_idle_timeout=PgbouncerConfig.DEFAULT_SERVER_IDLE_TIMEOUT,
-            server_lifetime=PgbouncerConfig.DEFAULT_SERVER_LIFETIME,
-        )
-        branch.pgbouncer_config = config
-        session.add(config)
-    else:
+        config = _default_pgbouncer_config()
         branch.pgbouncer_config = config
     return config
 

src/models/branch.py

@@ -83,7 +83,7 @@ class Branch(AsyncAttrs, Model, table=True):
 
     pgbouncer_config: Optional["PgbouncerConfig"] = Relationship(
         back_populates="branch",
-        sa_relationship_kwargs={"uselist": False, "cascade": "all, delete-orphan"},
+        cascade_delete=True,
     )
 
     database_size: Annotated[int, Field(**DATABASE_SIZE_CONSTRAINTS, sa_column=Column(BigInteger))]
@@ -213,7 +213,7 @@ class PgbouncerConfig(Model, table=True):
     DEFAULT_SERVER_IDLE_TIMEOUT: ClassVar[int | None] = PGBOUNCER_DEFAULT_SERVER_IDLE_TIMEOUT
     DEFAULT_SERVER_LIFETIME: ClassVar[int | None] = PGBOUNCER_DEFAULT_SERVER_LIFETIME
 
-    branch_id: Identifier = Model.foreign_key_field("branch", nullable=False, unique=True)
+    branch_id: Identifier = Model.foreign_key_field("branch", ondelete="CASCADE", unique=True)
     branch: Branch = Relationship(back_populates="pgbouncer_config")
 
     max_client_conn: Annotated[int | None, Field(default=None, ge=1)]

src/models/migrations/versions/07822c477427_pgbouncerconfig_branch_id_cascade.py

@@ -0,0 +1,36 @@
+"""pgbouncerconfig_branch_id_cascade
+
+Revision ID: 07822c477427
+Revises: 2b4e8f1a6c03
+Create Date: 2026-04-01 13:25:49.096508
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+import sqlmodel.sql
+
+
+# revision identifiers, used by Alembic.
+revision: str = '07822c477427'
+down_revision: Union[str, Sequence[str], None] = '2b4e8f1a6c03'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_constraint(op.f('pgbouncerconfig_branch_id_fkey'), 'pgbouncerconfig', type_='foreignkey')
+    op.create_foreign_key(op.f('pgbouncerconfig_branch_id_fkey'), 'pgbouncerconfig', 'branch', ['branch_id'], ['id'], ondelete='CASCADE')
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_constraint(op.f('pgbouncerconfig_branch_id_fkey'), 'pgbouncerconfig', type_='foreignkey')
+    op.create_foreign_key(op.f('pgbouncerconfig_branch_id_fkey'), 'pgbouncerconfig', 'branch', ['branch_id'], ['id'])
+    # ### end Alembic commands ###