payload: refactor APIs that return lists to return newtypes

The newtypes are effectively just pure wrappers so that we can
write instances for them later. Used in a follow up diff.

Change-Id: Ice2ec720247bb7b7cdaa5e72f9b3953b11b65300

src/Chainweb/Payload.hs

@@ -61,7 +61,8 @@ module Chainweb.Payload
 , verifyBlockPayload
 
 -- * Binary encodings
-
+, PayloadDataList(..)
+, PayloadWithOutputsList(..)
 , encodeBlockPayloads
 , decodeBlockPayloads
 , encodeBlockTransactions
@@ -494,6 +495,25 @@ data BlockTransactions_ a = BlockTransactions
     }
     deriving (Show, Eq, Ord, Generic)
 
+-- -------------------------------------------------------------------------- --
+-- Type-wrappers for some REST API endpoints
+
+-- We want to use application/octet-stream as the content type for types
+-- like [PayloadData], but doing that requires encoding the list specifically
+-- with a specific binary instance. write some newtype wrappers to do this
+-- with a specific encoding function, so we can then later write MimeRender
+-- and MimeUnrender instances
+
+newtype PayloadDataList = PayloadDataList { _payloadDataList :: [PayloadData] }
+    deriving (Show, Eq, Generic)
+    deriving anyclass (NFData)
+    deriving newtype (ToJSON, FromJSON)
+
+newtype PayloadWithOutputsList = PayloadWithOutputsList { _payloadWithOutputsList :: [PayloadWithOutputs] }
+    deriving (Show, Eq, Generic)
+    deriving anyclass (NFData)
+    deriving newtype (ToJSON, FromJSON)
+
 -- -------------------------------------------------------------------------- --
 
 encodeBlockPayloads :: BlockPayload_ a -> B.ByteString

src/Chainweb/Payload/RestAPI.hs

@@ -162,7 +162,7 @@ type PayloadPostApi_
     = "payload"
     :> "batch"
     :> ReqBody '[JSON] BatchBody
-    :> Post '[JSON] [PayloadData]
+    :> Post '[JSON] PayloadDataList
 
 type PayloadPostApi (v :: ChainwebVersionT) (c :: ChainIdT)
     = 'ChainwebEndpoint v :> ChainEndpoint c :> PayloadPostApi_
@@ -205,7 +205,7 @@ type OutputsPostApi_
     :> "outputs"
     :> "batch"
     :> ReqBody '[JSON] BatchBody
-    :> Post '[JSON] [PayloadWithOutputs]
+    :> Post '[JSON] PayloadWithOutputsList
 
 type OutputsPostApi (v :: ChainwebVersionT) (c :: ChainIdT)
     = 'ChainwebEndpoint v :> ChainEndpoint c :> OutputsPostApi_

src/Chainweb/Payload/RestAPI/Client.hs

@@ -67,7 +67,7 @@ payloadBatchClient_
     . KnownChainwebVersionSymbol v
     => KnownChainIdSymbol c
     => BatchBody
-    -> ClientM [PayloadData]
+    -> ClientM PayloadDataList
 payloadBatchClient_ = client (payloadPostApi @v @c)
 
 -- The query may return any number (including none) of the requested payload
@@ -77,7 +77,7 @@ payloadBatchClient
     :: ChainwebVersion
     -> ChainId
     -> BatchBody
-    -> ClientM [PayloadData]
+    -> ClientM PayloadDataList
 payloadBatchClient v c k = runIdentity $ do
     SomeChainwebVersionT (_ :: Proxy v) <- return $ someChainwebVersionVal v
     SomeChainIdT (_ :: Proxy c) <- return $ someChainIdVal c
@@ -114,14 +114,14 @@ outputsBatchClient_
     . KnownChainwebVersionSymbol v
     => KnownChainIdSymbol c
     => BatchBody
-    -> ClientM [PayloadWithOutputs]
+    -> ClientM PayloadWithOutputsList
 outputsBatchClient_ = client (outputsPostApi @v @c)
 
 outputsBatchClient
     :: ChainwebVersion
     -> ChainId
     -> BatchBody
-    -> ClientM [PayloadWithOutputs]
+    -> ClientM PayloadWithOutputsList
 outputsBatchClient v c k = runIdentity $ do
     SomeChainwebVersionT (_ :: Proxy v) <- return $ someChainwebVersionVal v
     SomeChainIdT (_ :: Proxy c) <- return $ someChainIdVal c

src/Chainweb/Payload/RestAPI/Server.hs

@@ -88,9 +88,9 @@ payloadBatchHandler
     => PayloadBatchLimit
     -> PayloadDb tbl
     -> BatchBody
-    -> Handler [PayloadData]
+    -> Handler PayloadDataList
 payloadBatchHandler batchLimit db ks
-  = liftIO (catMaybes <$> lookupPayloadDataWithHeightBatch db ks')
+  = liftIO (PayloadDataList . catMaybes <$> lookupPayloadDataWithHeightBatch db ks')
   where
       limit = take (int batchLimit)
       ks' | WithoutHeights xs <- ks = limit (fmap (Nothing,) xs)
@@ -122,9 +122,9 @@ outputsBatchHandler
     => PayloadBatchLimit
     -> PayloadDb tbl
     -> BatchBody
-    -> Handler [PayloadWithOutputs]
+    -> Handler PayloadWithOutputsList
 outputsBatchHandler batchLimit db ks
-  = liftIO (catMaybes <$> lookupPayloadWithHeightBatch db ks')
+  = liftIO (PayloadWithOutputsList . catMaybes <$> lookupPayloadWithHeightBatch db ks')
   where
       limit = take (int batchLimit)
       ks' | WithoutHeights xs <- ks = limit (fmap (Nothing,) xs)

tools/cwtool/TxSimulator.hs

@@ -285,7 +285,7 @@ fetchOutputs sc cenv bhs = do
     outputsBatchClient (scVersion sc) (scChain sc) (WithHeights $ map (\bh -> (_blockHeight bh, _blockPayloadHash bh)) bhs)
   case r of
     Left e -> throwM e
-    Right ps -> return ps
+    Right ps -> return (_payloadWithOutputsList ps)
 
 simulateMain :: IO ()
 simulateMain = do