fix: NOTIFY pgrst not reoading the catalog cache

CHANGELOG.md

@@ -14,6 +14,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
  - #2569, Replace misleading error message when no relationship is found with a hint containing parent/child names suggestions - @laurenceisla
  - #1405, Add the required OpenAPI items object when the parameter is an array - @laurenceisla
  - #2592, Add upsert headers for POST requests to the OpenAPI output - @laurenceisla
+ - #2620, Fix `NOTIFY pgrst` not reloading the db connections catalog cache - @steve-chavez
 
 ## [10.1.1] - 2022-11-08
 

src/PostgREST/Workers.hs

@@ -230,16 +230,15 @@ listener appState = do
       listener appState
 
     handleNotification _ msg
-      | BS.null msg            = scLoader -- reload the schema cache
+      | BS.null msg            = cacheReloader
-      | msg == "reload schema" = scLoader -- reload the schema cache
+      | msg == "reload schema" = cacheReloader
-      | msg == "reload config" = reReadConfig False appState -- reload the config
+      | msg == "reload config" = reReadConfig False appState
       | otherwise              = pure () -- Do nothing if anything else than an empty message is sent
 
-    scLoader =
+    cacheReloader =
-      -- It's not necessary to check the loadSchemaCache success
+      -- reloads the schema cache + restarts pool connections
-      -- here. If the connection drops, the thread will die and
+      -- it's necessary to restart the pg connections because they cache the pg catalog(see #2620)
-      -- proceed to recover.
+      connectionWorker appState
-      void $ loadSchemaCache appState
 
 -- | Re-reads the config plus config options from the db
 reReadConfig :: Bool -> AppState -> IO ()

test/io/fixtures.sql

@@ -86,3 +86,15 @@ $$ language sql;
 create or replace function hello() returns text as $$
   select 'hello';
 $$ language sql;
+
+create table cats(id uuid primary key, name text);
+grant all on cats to postgrest_test_anonymous;
+
+create function drop_change_cats() returns void
+language sql security definer
+as $$
+  drop table cats;
+  create table cats(id bigint primary key, name text);
+  grant all on table cats to postgrest_test_anonymous;
+  notify pgrst, 'reload schema';
+$$;

test/io/test_io.py

@@ -334,7 +334,7 @@ def test_db_schema_notify_reload(defaultenv):
             "/rpc/change_db_schema_and_full_reload", data={"schemas": "v1"}
         )
 
-        time.sleep(0.1)
+        time.sleep(0.2)
 
         response = postgrest.session.get("/rpc/get_guc_value?name=search_path")
         assert response.text == '"\\"v1\\", \\"public\\""'
@@ -827,6 +827,27 @@ def test_no_pool_connection_required_on_bad_embedding(defaultenv):
         assert response.status_code == 400
 
 
+def test_notify_reloading_catalog_cache(defaultenv):
+    "notify should reload the connection catalog cache"
+
+    with run(env=defaultenv) as postgrest:
+
+        # first the id col is an uuid
+        response = postgrest.session.get(
+            "/cats?id=eq.dea27321-f988-4a57-93e4-8eeb38f3cf1e"
+        )
+        assert response.status_code == 200
+
+        # change it to a bigint
+        response = postgrest.session.post("/rpc/drop_change_cats")
+        assert response.status_code == 204
+        time.sleep(0.1)
+
+        # next request should succeed with a bigint value
+        response = postgrest.session.get("/cats?id=eq.1")
+        assert response.status_code == 200
+
+
 # TODO: This test fails now because of https://github.com/PostgREST/postgrest/pull/2122
 # The stack size of 1K(-with-rtsopts=-K1K) is not enough and this fails with "stack overflow"
 # A stack size of 200K seems to be enough for succeess