Make runCommand compatible with MongoDB 6.0

Author: VictorDenisov

Database/MongoDB/Internal/Protocol.hs

@@ -581,6 +581,10 @@ putOpMsg cmd requestId flagBit params = do
                 putInt32 (bit $ bitOpMsg $ ExhaustAllowed)
                 putInt8 0
                 putDocument pre
+            Message{..} -> do
+                putInt32 biT
+                putInt8 0
+                putDocument $ merge [ "$db" =: mDatabase ] mParams
         Kc k -> case k of
             KillC{..} -> do
                 let n = T.splitOn "." kFullCollection
@@ -656,7 +660,11 @@ data Request =
     } | GetMore {
         gFullCollection :: FullCollection,
         gBatchSize :: Int32,
-        gCursorId :: CursorId}
+        gCursorId :: CursorId
+    } | Message {
+        mDatabase :: Text,
+        mParams :: Document
+    }
     deriving (Show, Eq)
 
 data QueryOption =
@@ -676,6 +684,7 @@ data QueryOption =
 qOpcode :: Request -> Opcode
 qOpcode Query{} = 2004
 qOpcode GetMore{} = 2005
+qOpcode Message{} = 2013
 
 opMsgOpcode :: Opcode
 opMsgOpcode = 2013
@@ -696,6 +705,10 @@ putRequest request requestId = do
             putCString gFullCollection
             putInt32 gBatchSize
             putInt64 gCursorId
+        Message{..} -> do
+            putInt32 0
+            putInt8 0
+            putDocument $ merge [ "$db" =: mDatabase ] mParams
 
 qBit :: QueryOption -> Int32
 qBit TailableCursor = bit 1

Database/MongoDB/Query.hs

@@ -1272,9 +1272,9 @@ find q@Query{selection, batchSize} = do
         qr <- queryRequestOpMsg False q
         let newQr =
               case fst qr of
-                Req qry ->
-                  let (_db, coll) = splitDot (qFullCollection qry)
-                  in (Req $ qry {qSelector = merge (qSelector qry) [ "find" =: coll ]}, snd qr)
+                Req P.Query{..} ->
+                  let coll = last $ T.splitOn "." qFullCollection
+                  in (Req $ P.Query {qSelector = merge qSelector [ "find" =: coll ], ..}, snd qr)
                 -- queryRequestOpMsg only returns Cmd types constructed via Req
                 _ -> error "impossible"
         dBatch <- liftIO $ requestOpMsg pipe newQr []
@@ -1312,6 +1312,9 @@ findCommand q@Query{..} = do
         | predicate a = Just (f a)
         | otherwise   = Nothing
 
+isHandshake :: Document -> Bool
+isHandshake = (== ["isMaster" =: (1 :: Int32)])
+
 findOne :: (MonadIO m) => Query -> Action m (Maybe Document)
 -- ^ Fetch first document satisfying query or @Nothing@ if none satisfy it
 findOne q = do
@@ -1321,8 +1324,7 @@ findOne q = do
             rq <- liftIO $ request pipe [] qr
             Batch _ _ docs <- liftDB $ fulfill rq
             return (listToMaybe docs)
-        isHandshake = (== ["isMaster" =: (1 :: Int32)])  $ selector $ selection q :: Bool
-    if isHandshake
+    if isHandshake (selector $ selection q)
       then legacyQuery
       else do
         let sd = P.serverData pipe
@@ -1332,14 +1334,14 @@ findOne q = do
             qr <- queryRequestOpMsg False q {limit = 1}
             let newQr =
                   case fst qr of
-                    Req qry ->
-                      let (_db, coll) = splitDot (qFullCollection qry)
+                    Req P.Query{..} ->
+                      let coll = last $ T.splitOn "." qFullCollection
                           -- We have to understand whether findOne is called as
                           -- command directly. This is necessary since findOne is used via
                           -- runCommand as a vehicle to execute any type of commands and notices.
-                          labels = catMaybes $ map (\f -> look f $ qSelector qry) (noticeCommands ++ adminCommands) :: [Value]
+                          labels = catMaybes $ map (\f -> look f qSelector) (noticeCommands ++ adminCommands) :: [Value]
                       in if null labels
-                           then (Req $ qry {qSelector = merge (qSelector qry) [ "find" =: coll ]}, snd qr)
+                           then (Req P.Query {qSelector = merge qSelector [ "find" =: coll ], ..}, snd qr)
                            else qr
                     _ -> error "impossible"
             rq <- liftIO $ requestOpMsg pipe newQr []
@@ -1526,7 +1528,7 @@ requestOpMsg pipe (Req r, remainingLimit) params = do
   promise <- liftIOE ConnectionFailure $ P.callOpMsg pipe r Nothing params
   let protectedPromise = liftIOE ConnectionFailure promise
   return $ fromReply remainingLimit =<< protectedPromise
-requestOpMsg _ (Nc _, _) _ = error "requestOpMsg: Only messages of type Query are supported"
+requestOpMsg _ _ _ = error "requestOpMsg: Only messages of type Query are supported"
 
 fromReply :: Maybe Limit -> Reply -> DelayedBatch
 -- ^ Convert Reply to Batch or Failure
@@ -1844,9 +1846,29 @@ type Command = Document
 -- ^ A command is a special query or action against the database. See <http://www.mongodb.org/display/DOCS/Commands> for details.
 
 runCommand :: (MonadIO m) => Command -> Action m Document
--- ^ Run command against the database and return its result
-runCommand c = fromMaybe err <$> findOne (query c "$cmd") where
-    err = error $ "Nothing returned for command: " ++ show c
+runCommand params = do
+    pipe <- asks mongoPipe
+    if isHandshake params || maxWireVersion (P.serverData pipe) < 17
+      then runCommandLegacy pipe params
+      else runCommand' pipe params
+
+runCommandLegacy :: MonadIO m => Pipe -> Selector -> ReaderT MongoContext m Document
+runCommandLegacy pipe params = do
+    qr <- queryRequest False (query params "$cmd") {limit = 1}
+    rq <- liftIO $ request pipe [] qr
+    Batch _ _ docs <- liftDB $ fulfill rq
+    case docs of
+      [doc] -> pure doc
+      _ -> error $ "Nothing returned for command: " <> show params
+
+runCommand' :: MonadIO m => Pipe -> Selector -> ReaderT MongoContext m Document
+runCommand' pipe params = do
+    ctx <- ask
+    rq <- liftIO $ requestOpMsg pipe ( Req (P.Message (mongoDatabase ctx) params), Just 1) []
+    Batch _ _ docs <- liftDB $ fulfill rq
+    case docs of
+      [doc] -> pure doc
+      _ -> error $ "Nothing returned for command: " <> show params
 
 runCommand1 :: (MonadIO m) => Text -> Action m Document
 -- ^ @runCommand1 foo = runCommand [foo =: 1]@