server: lower the isolation level to ReadCommited while inserting/updating invocation logs and events (#5824)

https://github.com/hasura/graphql-engine/pull/5824

server/src-lib/Hasura/Eventing/EventTrigger.hs

@@ -246,21 +246,21 @@ processEventQueue logger logenv httpMgr pool getSchemaCache eeCtx@EventEngineCtx
       => Event -> io ()
     processEvent e = do
       cache <- liftIO getSchemaCache
-      
+
       tracingCtx <- liftIO (Tracing.extractEventContext (eEvent e))
       let spanName eti = "Event trigger: " <> unNonEmptyText (unTriggerName (etiName eti))
           runTraceT = maybe
             Tracing.runTraceT
             Tracing.runTraceTInContext
             tracingCtx
-      
+
       case getEventTriggerInfoFromEvent cache e of
         Left err -> do
           --  This rare error can happen in the following known cases:
           --  i) schema cache is not up-to-date (due to some bug, say during schema syncing across multiple instances)
           --  ii) the event trigger is dropped when this event was just fetched
           logQErr $ err500 Unexpected err
-          liftIO . runExceptT $ Q.runTx pool (Q.RepeatableRead, Just Q.ReadWrite) $ do
+          liftIO . runExceptT $ Q.runTx pool (Q.ReadCommitted, Just Q.ReadWrite) $ do
             currentTime <- liftIO getCurrentTime
             -- For such an event, we unlock the event and retry after a minute
             setRetry e (addUTCTime 60 currentTime)
@@ -324,7 +324,7 @@ processSuccess pool e decodedHeaders ep resp = do
       respHeaders = hrsHeaders resp
       respStatus = hrsStatus resp
       invocation = mkInvocation ep respStatus decodedHeaders respBody respHeaders
-  liftIO $ runExceptT $ Q.runTx pool (Q.RepeatableRead, Just Q.ReadWrite) $ do
+  liftIO $ runExceptT $ Q.runTx pool (Q.ReadCommitted, Just Q.ReadWrite) $ do
     insertInvocation invocation
     setSuccess e
 
@@ -348,7 +348,7 @@ processError pool e retryConf decodedHeaders ep err = do
         HOther detail -> do
           let errMsg = (TBS.fromLBS $ encode detail)
           mkInvocation ep 500 decodedHeaders errMsg []
-  liftIO $ runExceptT $ Q.runTx pool (Q.RepeatableRead, Just Q.ReadWrite) $ do
+  liftIO $ runExceptT $ Q.runTx pool (Q.ReadCommitted, Just Q.ReadWrite) $ do
     insertInvocation invocation
     retryOrSetError e retryConf err
 
@@ -421,7 +421,7 @@ fetchEvents limitI =
       SET locked = NOW()
       WHERE id IN ( SELECT l.id
                     FROM hdb_catalog.event_log l
-                    WHERE l.delivered = 'f' and l.error = 'f' 
+                    WHERE l.delivered = 'f' and l.error = 'f'
                           and (l.locked IS NULL or l.locked < (NOW() - interval '30 minute'))
                           and (l.next_retry_at is NULL or l.next_retry_at <= now())
                           and l.archived = 'f'

server/src-lib/Hasura/Eventing/ScheduledTrigger.hs

@@ -542,7 +542,7 @@ processError pgpool se decodedHeaders type' reqJson err = do
           let errMsg = (TBS.fromLBS $ J.encode detail)
           mkInvocation se 500 decodedHeaders errMsg [] reqJson
   liftExceptTIO $
-    Q.runTx pgpool (Q.RepeatableRead, Just Q.ReadWrite) $ do
+    Q.runTx pgpool (Q.ReadCommitted, Just Q.ReadWrite) $ do
     insertInvocation invocation type'
     retryOrMarkError se err type'
 
@@ -610,14 +610,14 @@ processSuccess pgpool se decodedHeaders type' reqBodyJson resp = do
       respStatus = hrsStatus resp
       invocation = mkInvocation se respStatus decodedHeaders respBody respHeaders reqBodyJson
   liftExceptTIO $
-    Q.runTx pgpool (Q.RepeatableRead, Just Q.ReadWrite) $ do
+    Q.runTx pgpool (Q.ReadCommitted, Just Q.ReadWrite) $ do
     insertInvocation invocation type'
     setScheduledEventStatus (sefId se) SESDelivered type'
 
 processDead :: (MonadIO m, MonadError QErr m) => Q.PGPool -> ScheduledEventFull -> ScheduledEventType -> m ()
 processDead pgpool se type' =
   liftExceptTIO $
-  Q.runTx pgpool (Q.RepeatableRead, Just Q.ReadWrite) $
+  Q.runTx pgpool (Q.ReadCommitted, Just Q.ReadWrite) $
     setScheduledEventStatus (sefId se) SESDead type'
 
 setRetry :: ScheduledEventFull -> UTCTime -> ScheduledEventType ->  Q.TxE QErr ()