Merge pull request #221 from diogob/allow_virtual_fields_in_where

Qualifies columns of WHERE clauses so we can use computed columns as filters

src/PostgREST/App.hs

@@ -51,9 +51,9 @@ app conf reqBody req =
       return $ responseLBS status200 [jsonH] $ cs body
 
     ([table], "OPTIONS") -> do
-      let t = QualifiedTable schema (cs table)
+      let qt = qualify table
-      cols <- columns t
+      cols <- columns qt
-      pkey <- map cs <$> primaryKeyColumns t
+      pkey <- map cs <$> primaryKeyColumns qt
       return $ responseLBS status200 [jsonH, allOrigins]
         $ encode (TableOptions cols pkey)
 
@@ -61,15 +61,15 @@ app conf reqBody req =
       if range == Just emptyRange
       then return $ responseLBS status416 [] "HTTP Range error"
       else do
-        let qt = QualifiedTable schema (cs table)
+        let qt = qualify table
-        let select = B.Stmt "select " V.empty True <>
+            select = B.Stmt "select " V.empty True <>
                   parentheticT (
-                    whereT qq $ countRows qt
+                    whereT qt qq $ countRows qt
                   ) <> commaq <> (
                   asJsonWithCount
                   . limitT range
                   . orderT (orderParse qq)
-                  . whereT qq
+                  . whereT qt qq
                   $ selectStar qt
                 )
         row <- H.maybeEx select
@@ -128,7 +128,7 @@ app conf reqBody req =
                   encode . object $ [("message", String "Failed authentication.")]
 
     ([table], "POST") -> do
-      let qt = QualifiedTable schema (cs table)
+      let qt = qualify table
           echoRequested = lookup "Prefer" hdrs == Just "return=representation"
           parsed :: Either String (V.Vector Text, V.Vector (V.Vector Value))
           parsed = if lookup "Content-Type" hdrs == Just "text/csv"
@@ -164,7 +164,7 @@ app conf reqBody req =
 
     ([table], "PUT") ->
       handleJsonObj reqBody $ \obj -> do
-        let qt = QualifiedTable schema (cs table)
+        let qt = qualify table
         primaryKeys <- primaryKeyColumns qt
         let specifiedKeys = map (cs . fst) qq
         if S.fromList primaryKeys /= S.fromList specifiedKeys
@@ -177,7 +177,7 @@ app conf reqBody req =
               then do
                 let vals = M.elems obj
                 H.unitEx $ iffNotT
-                        (whereT qq $ update qt cols vals)
+                        (whereT qt qq $ update qt cols vals)
                         (insertSelect qt cols vals)
                 return $ responseLBS status204 [ jsonH ] ""
 
@@ -188,9 +188,9 @@ app conf reqBody req =
 
     ([table], "PATCH") ->
       handleJsonObj reqBody $ \obj -> do
-        let qt = QualifiedTable schema (cs table)
+        let qt = qualify table
             up = returningStarT
-               . whereT qq
+               . whereT qt qq
                $ update qt (map cs $ M.keys obj) (M.elems obj)
             patch = withT up "t" $ B.Stmt
               "select count(t), array_to_json(array_agg(row_to_json(t)))::character varying"
@@ -207,10 +207,10 @@ app conf reqBody req =
         return $ responseLBS s [ jsonH, r ] $ if echoRequested then cs $ fromMaybe "[]" body else ""
 
     ([table], "DELETE") -> do
-      let qt = QualifiedTable schema (cs table)
+      let qt = qualify table
       let del = countT
             . returningStarT
-            . whereT qq
+            . whereT qt qq
             $ deleteFrom qt
       row <- H.maybeEx del
       let (Identity deletedCount) = fromMaybe (Identity 0 :: Identity Int) row
@@ -225,6 +225,7 @@ app conf reqBody req =
     path          = pathInfo req
     verb          = requestMethod req
     qq            = queryString req
+    qualify       = QualifiedTable schema
     hdrs          = requestHeaders req
     schema        = requestedSchema (cs $ configV1Schema conf) hdrs
     authenticator = cs $ configDbUser conf

src/PostgREST/PgQuery.hs

@@ -51,14 +51,15 @@ limitT r q =
     limit  = maybe "ALL" (cs . show) $ join $ rangeLimit <$> r
     offset = cs . show $ fromMaybe 0 $ rangeOffset <$> r
 
-whereT :: Net.Query -> StatementT
+whereT :: QualifiedTable -> Net.Query -> StatementT
-whereT params q =
+whereT table params q =
  if L.null cols
    then q
    else q <> B.Stmt " where " empty True <> conjunction
  where
    cols = [ col | col <- params, fst col `notElem` ["order"] ]
-   conjunction = mconcat $ L.intersperse andq (map wherePred cols)
+   wherePredTable = wherePred table
+   conjunction = mconcat $ L.intersperse andq (map wherePredTable cols)
 
 withT :: PStmt -> T.Text -> StatementT
 withT (B.Stmt eq ep epre) v (B.Stmt wq wp wpre) =
@@ -154,9 +155,9 @@ update t cols vals = B.Stmt
     <> ")")
   empty True
 
-wherePred :: Net.QueryItem -> PStmt
+wherePred :: QualifiedTable -> Net.QueryItem -> PStmt
-wherePred (col, predicate) =
+wherePred table (col, predicate) =
-  B.Stmt (" " <> pgFmtJsonbPath (cs col) <> " " <> op <> " " <>
+  B.Stmt (" " <> pgFmtJsonbPath table (cs col) <> " " <> op <> " " <>
       if opCode `elem` ["is","isnot"] then whiteList value
                                  else cs sqlValue)
       empty True
@@ -237,11 +238,11 @@ parseJsonbPath p =
         (KeyIdentifier b)
     _ -> Nothing
 
-pgFmtJsonbPath :: T.Text -> T.Text
+pgFmtJsonbPath :: QualifiedTable -> T.Text -> T.Text
-pgFmtJsonbPath p =
+pgFmtJsonbPath table p =
   pgFmtJsonbPath' $ fromMaybe (ColIdentifier p) (parseJsonbPath p)
   where
-    pgFmtJsonbPath' (ColIdentifier i) = pgFmtIdent i
+    pgFmtJsonbPath' (ColIdentifier i) = fromQt table <> "." <> pgFmtIdent i
     pgFmtJsonbPath' (KeyIdentifier i) = pgFmtLit i
     pgFmtJsonbPath' (SingleArrow a b) =
       pgFmtJsonbPath' a <> "->" <> pgFmtJsonbPath' b

test/Feature/InsertSpec.hs

@@ -266,6 +266,12 @@ spec = afterAll_ resetDb $ around withApp $ do
         liftIO $ simpleHeaders g
           `shouldSatisfy` matchHeader "Content-Range" "0-9/10"
 
+      it "can update based on a computed column" $
+        request methodPatch
+          "/items?always_true=eq.false"
+          [("Prefer", "return=representation")]
+          [json| { id: 100 } |]
+          `shouldRespondWith` 404
       it "can provide a representation" $ do
         _ <- post "/items"
           [json| { id: 1 } |]

test/Feature/QuerySpec.hs

@@ -63,6 +63,10 @@ spec =
       get "/tsearch?text_search_vector=@@.foo" `shouldRespondWith`
         "[{\"text_search_vector\":\"'bar':2 'foo':1\"}]"
 
+    it "matches with computed column" $
+      get "/items?always_true=eq.true" `shouldRespondWith`
+        "[{\"id\":1},{\"id\":2},{\"id\":3},{\"id\":4},{\"id\":5},{\"id\":6},{\"id\":7},{\"id\":8},{\"id\":9},{\"id\":10},{\"id\":11},{\"id\":12},{\"id\":13},{\"id\":14},{\"id\":15}]"
+
   describe "ordering response" $ do
     it "by a column asc" $
       get "/items?id=lte.2&order=id.asc"

test/fixtures/schema.sql

@@ -72,7 +72,6 @@ $$;
 
 ALTER FUNCTION postgrest.update_owner() OWNER TO postgrest_test;
 
-
 CREATE FUNCTION set_authors_only_owner() RETURNS trigger
     LANGUAGE plpgsql
     AS $$
@@ -368,6 +367,13 @@ SELECT pg_catalog.setval('articles_id_seq', 1, false);
 
 SET search_path = "1", pg_catalog;
 
+CREATE FUNCTION public.always_true("1".items) RETURNS boolean
+    LANGUAGE sql STABLE
+    AS $$ SELECT true $$;
+
+ALTER FUNCTION public.always_true("1".items) OWNER TO postgrest_test;
+
+
 
 ALTER TABLE ONLY authors_only
     ADD CONSTRAINT authors_only_pkey PRIMARY KEY (secret);
@@ -557,6 +563,11 @@ REVOKE ALL ON TABLE insertable_view_with_join FROM postgrest_test;
 GRANT ALL ON TABLE insertable_view_with_join TO postgrest_test;
 GRANT ALL ON TABLE insertable_view_with_join TO postgrest_anonymous;
 
+REVOKE ALL ON FUNCTION public.always_true("1".items) FROM PUBLIC;
+REVOKE ALL ON FUNCTION public.always_true("1".items) FROM postgrest_test;
+GRANT ALL ON FUNCTION public.always_true("1".items) TO postgrest_test;
+GRANT ALL ON FUNCTION public.always_true("1".items) TO postgrest_anonymous;
+
 
 SET search_path = postgrest, pg_catalog;