ability to order embeded items (closes #509)

CHANGELOG.md

@@ -10,6 +10,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 - Support "-" in column names - @ruslantalpa
 - Support column/node renaming `alias:column` - @ruslantalpa
 - Accept posts from HTML forms - @begriffs
+- Ability to order embedded entities - @ruslantalpa
 
 ### Fixed
 - Return 401 or 403 for access denied rather than 404 - @begriffs

docs/api/reading.md

@@ -172,6 +172,12 @@ GET /people?order=age.nullsfirst
 GET /people?order=age.desc.nullslast
 ```
 
+To filter the embedded items, you need to specify the tree path for the order param like so. 
+```HTTP
+GET /projects?select=id,name,tasks{id,name}&order=id.asc&tasks.order=name.ask
+```
+
+
 You can also use [computed
 columns](http://www.postgresql.org/docs/current/interactive/xfunc-sql.html#XFUNC-SQL-COMPOSITE-FUNCTIONS)
 to order the results, even though the computed
@@ -285,7 +291,7 @@ GET /projects?id=eq.1&select=id, name, client{*}
 
 Would embed in the `client` key the row referenced with `client_id`.
 
-The `alias` feature works for embedded entities and also for regular columns. This is useful in situations where for example you use different naming conventions in the database and frontend. 
+The `alias` feature works for embedded entities and also for regular columns. This is useful in situations where for example you use different naming conventions in the database and frontend.
 
 The following request will produce the output below:
 ```HTTP

src/PostgREST/ApiRequest.hs

@@ -77,8 +77,8 @@ data ApiRequest = ApiRequest {
   , iFilters :: [(String, String)]
   -- | &select parameter used to shape the response
   , iSelect :: String
-  -- | &order parameter
-  , iOrder :: Maybe String
+  -- | &order parameters for each level
+  , iOrder :: [(String,String)]
   -- | Alphabetized (canonical) request query string for response URLs
   , iCanonicalQS :: String
   -- | JSON Web Token
@@ -147,11 +147,11 @@ userApiRequest schema req reqBody =
   , iPreferRepresentation = representation
   , iPreferSingular = singular
   , iPreferCount = not $ singular || hasPrefer "count=none"
-  , iFilters = [ (k, fromJust v) | (k,v) <- qParams, k `notElem` ["select", "order"], isJust v ]
+  , iFilters = [ (cs k, fromJust v) | (k,v) <- qParams, isJust v, k /= "select", not (endingIn "order" k) ]
   , iSelect = if method == "DELETE"
               then "*"
               else fromMaybe "*" $ fromMaybe (Just "*") $ lookup "select" qParams
-  , iOrder = join $ lookup "order" qParams
+  , iOrder = [(cs k, fromJust v) | (k,v) <- qParams, isJust v, endingIn "order" k ]
   , iCanonicalQS = urlEncodeVars
      . sortBy (comparing fst)
      . map (join (***) cs)
@@ -181,6 +181,9 @@ userApiRequest schema req reqBody =
   tokenStr = case T.split (== ' ') (cs auth) of
     ("Bearer" : t : _) -> t
     _                  -> ""
+  endingIn:: T.Text -> T.Text -> Bool
+  endingIn word key = word == lastWord
+    where lastWord = last $ T.split (=='.') key
 
 -- PRIVATE ---------------------------------------------------------------
 

src/PostgREST/App.hs

@@ -280,10 +280,10 @@ augumentRequestWithJoin schema allRels request =
 
 buildReadRequest :: [Relation] -> ApiRequest -> Either Text ReadRequest
 buildReadRequest allRels apiRequest  =
-  augumentRequestWithJoin schema rels =<< first formatParserError (foldr addFilter <$> (addOrder <$> readRequest <*> ord) <*> flts)
+  augumentRequestWithJoin schema rels =<<
+  first formatParserError (foldr addFilter <$> (foldr addOrder <$> readRequest <*> ords) <*> flts)
   where
     selStr = iSelect apiRequest
-    orderS = iOrder apiRequest
     action = iAction apiRequest
     target = iTarget apiRequest
     (schema, rootTableName) = fromJust $ -- Make it safe
@@ -303,9 +303,9 @@ buildReadRequest allRels apiRequest  =
       _       -> allRels
       where fakeSourceRelations = mapMaybe (toSourceRelation rootTableName) allRels -- see comment in toSourceRelation
     readRequest = parse (pRequestSelect rootName) ("failed to parse select parameter <<"++selStr++">>") selStr
-    addOrder (Node (q,i) f) o = Node (q{order=o}, i) f
     flts = mapM pRequestFilter filters
-    ord = traverse (parse pOrder ("failed to parse order parameter <<"++fromMaybe "" orderS++">>")) orderS
+    orders = iOrder apiRequest
+    ords = mapM pRequestOrder orders
 
 buildMutateRequest :: ApiRequest -> Either Text MutateRequest
 buildMutateRequest apiRequest =
@@ -326,12 +326,24 @@ buildMutateRequest apiRequest =
     mutateFilters = filter (not . ( '.' `elem` ) . fst) $ iFilters apiRequest -- update/delete filters can be only on the root table
     cond = first formatParserError $ map snd <$> mapM pRequestFilter mutateFilters
 
+addFilterToNode :: Filter -> ReadRequest -> ReadRequest
+addFilterToNode flt (Node (q@Select {flt_=flts}, i) f) = Node (q {flt_=flt:flts}, i) f
+
 addFilter :: (Path, Filter) -> ReadRequest -> ReadRequest
-addFilter ([], flt) (Node (q@Select {flt_=flts}, i) forest) = Node (q {flt_=flt:flts}, i) forest
-addFilter (path, flt) (Node rn forest) =
+addFilter = addProperty addFilterToNode
+
+addOrderToNode :: [OrderTerm] -> ReadRequest -> ReadRequest
+addOrderToNode o (Node (q,i) f) = Node (q{order=Just o}, i) f
+
+addOrder :: (Path, [OrderTerm]) -> ReadRequest -> ReadRequest
+addOrder = addProperty addOrderToNode
+
+addProperty :: (a -> ReadRequest -> ReadRequest) -> (Path, a) -> ReadRequest -> ReadRequest
+addProperty f ([], a) n = f a n
+addProperty f (path, a) (Node rn forest) =
   case targetNode of
-    Nothing -> Node rn forest -- the filter is silenty dropped in the Request does not contain the required path
-    Just tn -> Node rn (addFilter (remainingPath, flt) tn:restForest)
+    Nothing -> Node rn forest -- the property is silenty dropped in the Request does not contain the required path
+    Just tn -> Node rn (addProperty f (remainingPath, a) tn:restForest)
   where
     targetNodeName:remainingPath = path
     (targetNode,restForest) = splitForest targetNodeName forest

src/PostgREST/Parsers.hs

@@ -38,6 +38,13 @@ pRequestFilter (k, v) = (,) <$> path <*> (Filter <$> fld <*> op <*> val)
     op = fst <$> opVal
     val = snd <$> opVal
 
+pRequestOrder :: (String, String) -> Either ParseError (Path, [OrderTerm])
+pRequestOrder (k, v) = (,) <$> path <*> ord
+  where
+    treePath = parse pTreePath ("failed to parser tree path (" ++ k ++ ")") k
+    path = fst <$> treePath
+    ord = parse pOrder ("failed to parse order (" ++ v ++ ")") v
+
 ws :: Parser Text
 ws = cs <$> many (oneOf " \t")
 

test/Feature/QuerySpec.hs

@@ -362,6 +362,28 @@ spec = do
     it "without other constraints" $
       get "/items?order=id.asc" `shouldRespondWith` 200
 
+    it "ordering embeded entities" $
+      get "/projects?id=eq.1&select=id, name, tasks{id, name}&tasks.order=name.asc" `shouldRespondWith`
+        [str|[{"id":1,"name":"Windows 7","tasks":[{"id":2,"name":"Code w7"},{"id":1,"name":"Design w7"}]}]|]
+
+    it "ordering embeded entities with alias" $
+      get "/projects?id=eq.1&select=id, name, the_tasks:tasks{id, name}&tasks.order=name.asc" `shouldRespondWith`
+        [str|[{"id":1,"name":"Windows 7","the_tasks":[{"id":2,"name":"Code w7"},{"id":1,"name":"Design w7"}]}]|]
+
+    it "ordering embeded entities, two levels" $
+      get "/projects?id=eq.1&select=id, name, tasks{id, name, users{id, name}}&tasks.order=name.asc&tasks.users.order=name.desc" `shouldRespondWith`
+        [str|[{"id":1,"name":"Windows 7","tasks":[{"id":2,"name":"Code w7","users":[{"id":1,"name":"Angela Martin"}]},{"id":1,"name":"Design w7","users":[{"id":3,"name":"Dwight Schrute"},{"id":1,"name":"Angela Martin"}]}]}]|]
+
+    it "ordering embeded parents does not break things" $
+      get "/projects?id=eq.1&select=id, name, clients{id, name}&clients.order=name.asc" `shouldRespondWith`
+        [str|[{"id":1,"name":"Windows 7","clients":{"id":1,"name":"Microsoft"}}]|]
+
+    it "ordering embeded parents does not break things when using ducktape names" $
+      get "/projects?id=eq.1&select=id, name, client{id, name}&client.order=name.asc" `shouldRespondWith`
+        [str|[{"id":1,"name":"Windows 7","client":{"id":1,"name":"Microsoft"}}]|]
+
+
+
   describe "Accept headers" $ do
     it "should respond an unknown accept type with 415" $
       request methodGet "/simple_pk"