Do not include Content-Type header for empty body (#580)

* Do not include Content-Type header for empty body

Fixes #544

* Fix lint

* Changelog

CHANGELOG.md

@@ -11,6 +11,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 
+- Omit Content-Type header for empty body - @begriffs
 - Prevent role from being changed twice - @begriffs
 - Use read-only transaction for read requests - @ruslantalpa
 

src/PostgREST/App.hs

@@ -127,12 +127,14 @@ app dbStructure conf apiRequest =
           let stm = createWriteStatement qi sq mq isSingle (iPreferRepresentation apiRequest) pKeys (contentType == TextCSV) payload
           row <- H.query uniform stm
           let (_, _, location, body) = extractQueryResult row
-          return $ responseLBS status201
-            [
-              contentTypeH,
-              (hLocation, "/" <> cs table <> "?" <> cs location)
-            ]
-            $ if iPreferRepresentation apiRequest == Full then cs body else ""
+
+          return $ if iPreferRepresentation apiRequest == Full
+            then responseLBS status201 [
+                  contentTypeH,
+                  (hLocation, "/" <> cs table <> "?" <> cs location)
+                ] (cs body)
+            else responseLBS status201
+              [(hLocation, "/" <> cs table <> "?" <> cs location)] ""
 
     (ActionUpdate, TargetIdent qi, Just payload@(PayloadJSON uniform)) ->
       case mutateSqlParts of
@@ -145,8 +147,9 @@ app dbStructure conf apiRequest =
               s = case () of _ | queryTotal == 0 -> status404
                                | iPreferRepresentation apiRequest == Full -> status200
                                | otherwise -> status204
-          return $ responseLBS s [contentTypeH, r]
-            $ if iPreferRepresentation apiRequest == Full then cs body else ""
+          return $ if iPreferRepresentation apiRequest == Full
+            then responseLBS s [contentTypeH, r] (cs body)
+            else responseLBS s [r] ""
 
     (ActionDelete, TargetIdent qi, Nothing) ->
       case mutateSqlParts of

test/Feature/InsertSpec.hs

@@ -32,6 +32,8 @@ spec = do
         liftIO $ do
           simpleBody p `shouldBe` ""
           simpleStatus p `shouldBe` created201
+          -- should not have content type set when body is empty
+          lookup hContentType (simpleHeaders p) `shouldBe` Nothing
 
       it "filters columns in result using &select" $
         request methodPost "/menagerie?select=integer,varchar" [("Prefer", "return=representation")]
@@ -312,13 +314,15 @@ spec = do
         g <- get "/items?id=eq.42"
         liftIO $ simpleHeaders g
           `shouldSatisfy` matchHeader "Content-Range" "\\*/0"
-        request methodPatch "/items?id=eq.2" []
-          [json| { "id":42 } |]
-            `shouldRespondWith` ResponseMatcher {
-              matchBody    = Nothing,
-              matchStatus  = 204,
-              matchHeaders = ["Content-Range" <:> "0-0/1"]
-            }
+        p <- request methodPatch "/items?id=eq.2" [] [json| { "id":42 } |]
+        pure p `shouldRespondWith` ResponseMatcher {
+            matchBody    = Nothing,
+            matchStatus  = 204,
+            matchHeaders = ["Content-Range" <:> "0-0/1"]
+          }
+        liftIO $
+          lookup hContentType (simpleHeaders p) `shouldBe` Nothing
+
         g' <- get "/items?id=eq.42"
         liftIO $ simpleHeaders g'
           `shouldSatisfy` matchHeader "Content-Range" "0-0/1"