feat: remove pg_cron dependency and related scheduling logic for improved flexibility

Author: jirhiker

alembic/versions/d5e6f7a8b9c0_create_pygeoapi_supporting_views.py

@@ -17,8 +17,6 @@
 branch_labels: Union[str, Sequence[str], None] = None
 depends_on: Union[str, Sequence[str], None] = None
 REFRESH_FUNCTION_NAME = "refresh_pygeoapi_materialized_views"
-REFRESH_JOB_NAME = "refresh_pygeoapi_matviews_nightly"
-REFRESH_SCHEDULE = "0 3 * * *"
 
 THING_COLLECTIONS = [
     ("water_wells", "water well"),
@@ -231,68 +229,6 @@ def _create_refresh_function() -> str:
     """
 
 
-def _schedule_refresh_job() -> str:
-    return f"""
-        DO $do$
-        BEGIN
-            BEGIN
-                -- Avoid direct SELECT on cron.job because managed Postgres
-                -- environments may deny access to the cron schema table.
-                PERFORM cron.unschedule('{REFRESH_JOB_NAME}');
-            EXCEPTION
-                WHEN undefined_function THEN
-                    NULL;
-                WHEN invalid_parameter_value THEN
-                    NULL;
-                WHEN internal_error THEN
-                    -- Some pg_cron builds raise internal_error when the named
-                    -- job does not exist. Treat this as already-unscheduled.
-                    NULL;
-                WHEN insufficient_privilege THEN
-                    RAISE NOTICE
-                        'Skipping pg_cron unschedule for % due to insufficient privileges.',
-                        '{REFRESH_JOB_NAME}';
-                    RETURN;
-            END;
-
-            PERFORM cron.schedule(
-                '{REFRESH_JOB_NAME}',
-                '{REFRESH_SCHEDULE}',
-                $cmd$SELECT public.{REFRESH_FUNCTION_NAME}();$cmd$
-            );
-        EXCEPTION
-            WHEN insufficient_privilege THEN
-                RAISE NOTICE
-                    'Skipping pg_cron schedule for % due to insufficient privileges.',
-                    '{REFRESH_JOB_NAME}';
-        END
-        $do$;
-    """
-
-
-def _unschedule_refresh_job() -> str:
-    return f"""
-        DO $do$
-        BEGIN
-            BEGIN
-                PERFORM cron.unschedule('{REFRESH_JOB_NAME}');
-            EXCEPTION
-                WHEN undefined_function THEN
-                    NULL;
-                WHEN invalid_parameter_value THEN
-                    NULL;
-                WHEN internal_error THEN
-                    NULL;
-                WHEN insufficient_privilege THEN
-                    RAISE NOTICE
-                        'Skipping pg_cron unschedule for % due to insufficient privileges.',
-                        '{REFRESH_JOB_NAME}';
-            END;
-        END
-        $do$;
-    """
-
-
 def upgrade() -> None:
     bind = op.get_bind()
     inspector = inspect(bind)
@@ -307,16 +243,6 @@ def upgrade() -> None:
             f"tables are missing: {missing_tables_str}"
         )
 
-    pg_cron_available = bind.execute(
-        text(
-            "SELECT EXISTS ("
-            "SELECT 1 FROM pg_available_extensions WHERE name = 'pg_cron'"
-            ")"
-        )
-    ).scalar()
-    if pg_cron_available:
-        op.execute(text("CREATE EXTENSION IF NOT EXISTS pg_cron"))
-
     for view_id, thing_type in THING_COLLECTIONS:
         safe_view_id = _safe_view_id(view_id)
         op.execute(text(f"DROP VIEW IF EXISTS ogc_{safe_view_id}"))
@@ -360,21 +286,9 @@ def upgrade() -> None:
     _create_matview_indexes()
 
     op.execute(text(_create_refresh_function()))
-    if pg_cron_available:
-        op.execute(text(_schedule_refresh_job()))
 
 
 def downgrade() -> None:
-    bind = op.get_bind()
-    pg_cron_available = bind.execute(
-        text(
-            "SELECT EXISTS ("
-            "SELECT 1 FROM pg_available_extensions WHERE name = 'pg_cron'"
-            ")"
-        )
-    ).scalar()
-    if pg_cron_available:
-        op.execute(text(_unschedule_refresh_job()))
     op.execute(text(f"DROP FUNCTION IF EXISTS public.{REFRESH_FUNCTION_NAME}()"))
     _drop_view_or_materialized_view("ogc_avg_tds_wells")
     _drop_view_or_materialized_view("ogc_latest_depth_to_water_wells")

core/initializers.py

@@ -13,8 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 # ===============================================================================
-from pathlib import Path
 import os
+from pathlib import Path
 
 from fastapi_pagination import add_pagination
 from sqlalchemy import text, select
@@ -66,15 +66,6 @@ def erase_and_rebuild_db():
         session.execute(text("DROP SCHEMA public CASCADE"))
         session.execute(text("CREATE SCHEMA public"))
         session.execute(text("CREATE EXTENSION IF NOT EXISTS postgis"))
-        pg_cron_available = session.execute(
-            text(
-                "SELECT EXISTS ("
-                "SELECT 1 FROM pg_available_extensions WHERE name = 'pg_cron'"
-                ")"
-            )
-        ).scalar()
-        if pg_cron_available:
-            session.execute(text("CREATE EXTENSION IF NOT EXISTS pg_cron"))
         session.commit()
         Base.metadata.drop_all(session.bind)
         Base.metadata.create_all(session.bind)

db/initialization.py

@@ -10,7 +10,8 @@
 
 from db import Base
 
-APP_READ_GRANT_SQL = text("""
+APP_READ_GRANT_SQL = text(
+    """
     DO $$
     BEGIN
         IF EXISTS (SELECT 1 FROM pg_roles WHERE rolname = 'app_read') THEN
@@ -19,7 +20,8 @@
             EXECUTE 'ALTER DEFAULT PRIVILEGES IN SCHEMA public GRANT SELECT ON TABLES TO app_read';
         END IF;
     END $$;
-    """)
+    """
+)
 
 
 def _parse_app_read_members() -> list[str]:
@@ -46,14 +48,16 @@ def grant_app_read_members(executor: Session | Connection | None) -> None:
     for member in members:
         safe_member = member.replace("'", "''")
         quoted = f'"{safe_member}"'
-        stmt = text(f"""
+        stmt = text(
+            f"""
             DO $$
             BEGIN
                 IF EXISTS (SELECT 1 FROM pg_roles WHERE rolname = '{safe_member}') THEN
                     EXECUTE 'GRANT app_read TO {quoted}';
                 END IF;
             END $$;
-            """)
+            """
+        )
         executor.execute(stmt)
 
 
@@ -62,15 +66,6 @@ def recreate_public_schema(session: Session) -> None:
     session.execute(text("DROP SCHEMA public CASCADE"))
     session.execute(text("CREATE SCHEMA public"))
     session.execute(text("CREATE EXTENSION IF NOT EXISTS postgis"))
-    pg_cron_available = session.execute(
-        text(
-            "SELECT EXISTS ("
-            "SELECT 1 FROM pg_available_extensions WHERE name = 'pg_cron'"
-            ")"
-        )
-    ).scalar()
-    if pg_cron_available:
-        session.execute(text("CREATE EXTENSION IF NOT EXISTS pg_cron"))
     session.execute(APP_READ_GRANT_SQL)
     grant_app_read_members(session)
     session.commit()

docker-compose.yml

@@ -6,10 +6,6 @@ services:
       context: .
       dockerfile: ./docker/db/Dockerfile
     platform: linux/amd64
-    command: >
-      postgres
-      -c shared_preload_libraries=pg_cron
-      -c cron.database_name=${POSTGRES_DB}
     environment:
       - POSTGRES_USER=${POSTGRES_USER}
       - POSTGRES_PASSWORD=${POSTGRES_PASSWORD}

docker/db/Dockerfile

@@ -1,5 +1 @@
 FROM postgis/postgis:17-3.5
-
-RUN apt-get update \
-    && apt-get install -y --no-install-recommends postgresql-17-cron \
-    && rm -rf /var/lib/apt/lists/*