Merge pull request #62 from hasura/issue-61

use row expressions instead of json_build_object, closes #61

server/src-lib/Hasura/RQL/DML/Internal.hs

@@ -233,15 +233,11 @@ mkColExtr (c, pct) =
   mkColExtrAl (Just c) (c, pct)
 
 mkColExtrAl :: (IsIden a) => Maybe a -> (PGCol, PGColType) -> S.Extractor
-mkColExtrAl alM colInfo =
-  S.mkAliasedExtrFromExp (mkColExp colInfo) alM
-
-mkColExp :: (PGCol, PGColType) -> S.SQLExp
-mkColExp (c, pct) =
+mkColExtrAl alM (c, pct) =
   if pct == PGGeometry || pct == PGGeography
-  then
-    (S.SEFnApp "ST_AsGeoJSON" [S.mkSIdenExp c] Nothing) `S.SETyAnn` "json"
-  else S.mkSIdenExp c
+  then S.mkAliasedExtrFromExp
+    ((S.SEFnApp "ST_AsGeoJSON" [S.mkSIdenExp c] Nothing) `S.SETyAnn` "json") alM
+  else S.mkAliasedExtr c alM
 
 -- validate headers
 validateHeaders :: (P1C m) => [T.Text] -> m ()

server/src-lib/Hasura/RQL/DML/Returning.hs

@@ -5,8 +5,8 @@
 
 module Hasura.RQL.DML.Returning where
 
-import           Hasura.RQL.DML.Internal
 import           Hasura.Prelude
+import           Hasura.RQL.DML.Internal
 import           Hasura.RQL.Types
 import           Hasura.SQL.Types
 
@@ -37,8 +37,8 @@ mkRetFldsExp :: RetFlds -> S.SQLExp
 mkRetFldsExp retFlds =
   S.mkRowExp $ flip map (Map.toList retFlds) $ \(k, retFld) ->
   case retFld of
-    RExp t       -> (k, S.SELit t)
-    RCol colInfo -> (k, mkColExp colInfo)
+    RExp t       -> S.mkAliasedExtrFromExp (S.SELit t) $ Just $ PGCol k
+    RCol colInfo -> mkColExtrAl (Just $ PGCol k) colInfo
 
 data MutFld
   = MCount

server/src-lib/Hasura/RQL/DML/Select.hs

@@ -404,9 +404,10 @@ mkJoinCond annRel =
 --
 --     { "col1" : v1, "col2" : v2 }
 
-mkInnerSelExtr :: (FieldName, AnnFld) -> (T.Text, S.SQLExp)
+mkInnerSelExtr :: (FieldName, AnnFld) -> S.Extractor
 mkInnerSelExtr (alias, annFld) =
-  (getFieldNameTxt alias, colExp)
+  S.mkAliasedExtrFromExp colExp $
+  Just alias
   where
     colExp = case annFld of
       FCol (pgCol, _) -> S.mkQIdenExp (TableName "r")  pgCol
@@ -420,20 +421,18 @@ mkLJCol (RelName rTxt) (PGCol cTxt) =
 -- | Generates
 --
 --   IF (r.__r_col IS NULL) THEN 'null' ELSE row_to_json(..)
-mkObjRelExtr :: PGCol -> RelName -> [(T.Text, S.SQLExp)] -> S.Extractor
+mkObjRelExtr :: PGCol -> RelName -> [S.Extractor] -> S.Extractor
 mkObjRelExtr compCol relName flds =
   let idCol   = S.mkQIdenExp (TableName "r") compCol
       rowExp  = S.mkRowExp flds
-      -- objAgg  = S.SEFnApp "row_to_json" [rowExp] Nothing
-      condExp = S.SECond (S.BENull idCol) (S.SELit "null") rowExp
+      objAgg  = S.SEFnApp "row_to_json" [rowExp] Nothing
+      condExp = S.SECond (S.BENull idCol) (S.SELit "null") objAgg
   in S.mkAliasedExtrFromExp condExp $ Just relName
 
 -- | Generates
 --
 --   IF (first(r.__r_col) IS NULL) THEN '[]' ELSE json_agg(..)
-mkArrRelExtr
-  :: (Maybe S.OrderByExp) -> PGCol
-  -> RelName -> [(T.Text, S.SQLExp)] -> S.Extractor
+mkArrRelExtr :: (Maybe S.OrderByExp) -> PGCol -> RelName -> [S.Extractor] -> S.Extractor
 mkArrRelExtr mOb compCol relName flds =
   let refCol  = S.SEFnApp "hdb_catalog.first"
                 [ S.mkQIdenExp (TableName "r") compCol ] Nothing

server/src-lib/Hasura/SQL/DML.hs

@@ -122,25 +122,20 @@ mkSelFromExp isLateral sel tn =
   where
     alias = Alias $ toIden tn
 
-mkRowExp :: [(T.Text, SQLExp)] -> SQLExp
-mkRowExp extrs =
-  SEFnApp "json_build_object" args Nothing
-  where
-    args = concat [[SELit t, r] | (t, r) <- extrs]
+mkRowExp :: [Extractor] -> SQLExp
+mkRowExp extrs = let
+  innerSel = mkSelect { selExtr = extrs }
 
-  -- let
-  -- innerSel = mkSelect { selExtr = extrs }
+  innerSelName = TableName "e"
 
-  -- innerSelName = TableName "e"
-
-  -- -- SELECT r FROM (SELECT col1, col2, .. ) AS r
-  -- outerSel = mkSelect
-  --            { selExtr = [mkExtr innerSelName]
-  --            , selFrom = Just $ FromExp
-  --                        [mkSelFromExp False innerSel innerSelName]
-  --            }
-  -- in
-  --   SESelect outerSel
+  -- SELECT r FROM (SELECT col1, col2, .. ) AS r
+  outerSel = mkSelect
+             { selExtr = [mkExtr innerSelName]
+             , selFrom = Just $ FromExp
+                         [mkSelFromExp False innerSel innerSelName]
+             }
+  in
+    SESelect outerSel
 
 newtype HavingExp
   = HavingExp BoolExp