db-sync: Handle rool back of PoolMetadataRef before result inserted

If a rollback occurs after the PoolMetadataRef is fetched, the insertion of the result can fail. In this insert fail case, we simply log and drop the exception. Closes: #806
IntersectMBO · Sep 12, 2021 · 36c96bc · 36c96bc
1 parent a206f9b
commit 36c96bc
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Showing 4 changed files with 20 additions and 9 deletions.
diff --git a/cardano-db-sync/cardano-db-sync.cabal b/cardano-db-sync/cardano-db-sync.cabal
@@ -102,6 +102,7 @@ library
                       , cardano-slotting
                       , containers
                       , esqueleto
+                      , exceptions
                       , extra
                       , groups
                       , http-client
@@ -118,6 +119,7 @@ library
                       , ouroboros-network
                       , persistent
                       , persistent-postgresql
+                      , postgresql-simple
                       , prometheus
                       , random-shuffle
                       , small-steps

diff --git a/cardano-db-sync/src/Cardano/DbSync/Era/Shelley/Insert.hs b/cardano-db-sync/src/Cardano/DbSync/Era/Shelley/Insert.hs
@@ -55,6 +55,7 @@ import           Cardano.Ledger.Mary.Value (AssetName (..), PolicyID (..), Value
 import           Cardano.Slotting.Block (BlockNo (..))
 import           Cardano.Slotting.Slot (EpochNo (..), EpochSize (..), SlotNo (..))
 
+import           Control.Monad.Catch (MonadCatch)
 import           Control.Monad.Class.MonadSTM.Strict (tryReadTBQueue)
 import           Control.Monad.Trans.Control (MonadBaseControl)
 
@@ -76,7 +77,7 @@ import qualified Shelley.Spec.Ledger.STS.Chain as Shelley
 import qualified Shelley.Spec.Ledger.TxBody as Shelley
 
 insertShelleyBlock
-    :: (MonadBaseControl IO m, MonadIO m)
+    :: (MonadBaseControl IO m, MonadCatch m, MonadIO m)
     => Trace IO Text -> LedgerEnv -> Generic.Block -> LedgerStateSnapshot -> SlotDetails
     -> ReaderT SqlBackend m (Either SyncNodeError ())
 insertShelleyBlock tracer lenv blk lStateSnap details = do

diff --git a/cardano-db-sync/src/Cardano/DbSync/Era/Shelley/Offline.hs b/cardano-db-sync/src/Cardano/DbSync/Era/Shelley/Offline.hs
@@ -11,16 +11,17 @@ module Cardano.DbSync.Era.Shelley.Offline
   , runOfflineFetchThread
   ) where
 
-import           Cardano.Prelude
+import           Cardano.Prelude hiding (handle)
 
-import           Cardano.BM.Trace (Trace, logInfo)
+import           Cardano.BM.Trace (Trace, logInfo, logWarning)
 
 import           Cardano.DbSync.Era.Shelley.Offline.Http
 import           Cardano.DbSync.Era.Shelley.Offline.Query
 import           Cardano.DbSync.Era.Shelley.Offline.Types
 
 import           Cardano.Sync.Types
 
+import           Control.Monad.Catch (MonadCatch, handle)
 import           Control.Monad.Class.MonadSTM.Strict (TBQueue, flushTBQueue, isEmptyTBQueue,
                    readTBQueue, writeTBQueue)
 import           Control.Monad.Trans.Control (MonadBaseControl)
@@ -43,6 +44,7 @@ import           Cardano.Sync.LedgerState
 import           Cardano.Sync.Util
 
 import           Database.Persist.Sql (SqlBackend)
+import           Database.PostgreSQL.Simple (SqlError)
 
 import           Network.HTTP.Client (HttpException (..))
 import qualified Network.HTTP.Client as Http
@@ -68,7 +70,7 @@ loadOfflineWorkQueue _trce workQueue =
     queueInsert = atomically . writeTBQueue workQueue
 
 insertOfflineResults
-    :: (MonadBaseControl IO m, MonadIO m)
+    :: (MonadBaseControl IO m, MonadCatch m, MonadIO m)
     => Trace IO Text -> TBQueue IO FetchResult -> ReaderT SqlBackend m ()
 insertOfflineResults trce resultQueue = do
     res <- liftIO . atomically $ flushTBQueue resultQueue
@@ -80,18 +82,23 @@ insertOfflineResults trce resultQueue = do
         ]
     mapM_ insert res
   where
-    insert :: (MonadBaseControl IO m, MonadIO m) => FetchResult -> ReaderT SqlBackend m ()
+    insert :: (MonadBaseControl IO m, MonadCatch m, MonadIO m) => FetchResult -> ReaderT SqlBackend m ()
     insert fr =
-      case fr of
-        ResultMetadata md -> void $ DB.insertPoolOfflineData md
-        ResultError fe -> void $ DB.insertPoolOfflineFetchError fe
+      -- If a rollback occurs after the PoolMetadataRef is fetched, the insertion of the
+      -- result can fail. In this insert fail case, we simply log and drop the exception.
+      handle (liftIO . logFail) $
+        case fr of
+          ResultMetadata md -> void $ DB.insertPoolOfflineData md
+          ResultError fe -> void $ DB.insertPoolOfflineFetchError fe
 
     isFetchError :: FetchResult -> Bool
     isFetchError fe =
        case fe of
         ResultMetadata {} -> False
         ResultError {} -> True
 
+    logFail :: SqlError -> IO ()
+    logFail e = logWarning trce $ "insertOfflineResults: " <> textShow e
 
 runOfflineFetchThread :: Trace IO Text -> LedgerEnv -> IO ()
 runOfflineFetchThread trce lenv = do

diff --git a/cardano-db-sync/src/Cardano/DbSync/Plugin/Default.hs b/cardano-db-sync/src/Cardano/DbSync/Plugin/Default.hs
@@ -38,6 +38,7 @@ import           Cardano.Sync.Plugin
 import           Cardano.Sync.Types
 import           Cardano.Sync.Util
 
+import           Control.Monad.Catch (MonadCatch)
 import           Control.Monad.Class.MonadSTM.Strict (putTMVar, tryTakeTMVar)
 import           Control.Monad.Trans.Control (MonadBaseControl)
 import           Control.Monad.Trans.Except.Extra (newExceptT)
@@ -73,7 +74,7 @@ insertDefaultBlock backend tracer env blockDetails = do
       runExceptT (traverse_ insert blockDetails)
   where
     insert
-        :: (MonadBaseControl IO m, MonadIO m)
+        :: (MonadBaseControl IO m, MonadCatch m, MonadIO m)
         => BlockDetails -> ExceptT SyncNodeError (ReaderT SqlBackend m) ()
     insert (BlockDetails cblk details) = do
       -- Calculate the new ledger state to pass to the DB insert functions but do not yet