feat: add related filters

src/PostgREST/ApiRequest/QueryParams.hs

@@ -79,7 +79,7 @@ data QueryParams =
     , qsSelect         :: [Tree SelectItem]
     -- ^ &select parameter used to shape the response
     , qsFilters        :: [(EmbedPath, Filter)]
-    -- ^ Filters on the result from e.g. &id=e.10
+    -- ^ Filters on the result from e.g. &id=eq.10
     , qsFiltersRoot    :: [Filter]
     -- ^ Subset of the filters that apply on the root table. These are used on UPDATE/DELETE.
     , qsFiltersNotRoot :: [(EmbedPath, Filter)]
@@ -227,15 +227,24 @@ pRequestOnConflict oncStr =
 -- >>> pRequestFilter True ("id", "val")
 -- Right ([],Filter {field = ("id",[]), opExpr = NoOpExpr "val"})
 pRequestFilter :: Bool -> (Text, Text) -> Either QPError (EmbedPath, Filter)
-pRequestFilter isRpcRead (k, v) = mapError $ (,) <$> path <*> (Filter <$> fld <*> oper)
+pRequestFilter isRpcRead (k, v) = mapError $ (,) <$> path <*> (flt <*> oper)
   where
-    treePath = P.parse pTreePath ("failed to parse tree path (" ++ toS k ++ ")") $ toS k
+    treePath = P.parse (try pRelTreePath <|> pTreePath') ("failed to parse tree path (" ++ toS k ++ ")") $ toS k
+    path = fst <$> treePath
+    flt = snd <$> treePath
     oper = P.parse parseFlt ("failed to parse filter (" ++ toS v ++ ")") $ toS v
     parseFlt = if isRpcRead
       then pOpExpr pSingleVal <|> pure (NoOpExpr v)
       else pOpExpr pSingleVal
-    path = fst <$> treePath
-    fld = snd <$> treePath
+
+    pTreePath' :: Parser (EmbedPath, OpExpr -> Filter)
+    pTreePath' = second Filter <$> pTreePath
+
+    pRelTreePath :: Parser (EmbedPath, OpExpr -> Filter)
+    pRelTreePath = do
+      p <- pFieldName `sepBy1` pDelimiter
+      f <- between (char '(') (char ')') pField
+      return (init p, RelFilter (last p) f)
 
 pRequestOrder :: (Text, Text) -> Either QPError (EmbedPath, [OrderTerm])
 pRequestOrder (k, v) = mapError $ (,) <$> path <*> ord'
@@ -813,11 +822,18 @@ pOrder = lexeme (try pOrderRelationTerm <|> pOrderTerm) `sepBy1` char ','
 -- unexpected "x"
 -- expecting logic operator (and, or)
 pLogicTree :: Parser LogicTree
-pLogicTree = Stmnt <$> try pLogicFilter
+pLogicTree = try pLogicEmbedFilter
+             <|> Stmnt <$> try pLogicFilter
              <|> Expr <$> pNot <*> pLogicOp <*> (lexeme (char '(') *> pLogicTree `sepBy1` lexeme (char ',') <* lexeme (char ')'))
   where
     pLogicFilter :: Parser Filter
     pLogicFilter = Filter <$> pField <* pDelimiter <*> pOpExpr pLogicSingleVal
+    pLogicEmbedFilter :: Parser LogicTree
+    pLogicEmbedFilter = do
+      pth <- pFieldName
+      fld <- between (char '(') (char ')') pField
+      opx <- pDelimiter *> pOpExpr pLogicSingleVal
+      return $ Stmnt (RelFilter pth fld opx)
     pNot :: Parser Bool
     pNot = try (string "not" *> pDelimiter $> True)
            <|> pure False

src/PostgREST/ApiRequest/Types.hs

@@ -148,9 +148,14 @@
 
 data Filter
   = Filter
-  { field  :: Field
-  , opExpr :: OpExpr
-  }
+    { field  :: Field
+    , opExpr :: OpExpr
+    }
+  | RelFilter
+    { relation :: FieldName
+    , field    :: Field
+    , opExpr   :: OpExpr
+    }
   deriving (Eq, Show)
 
 data OpExpr

src/PostgREST/Plan.hs

@@ -797,19 +797,38 @@ findTable qi@QualifiedIdentifier{..} tableMap =
 
 addFilters :: ResolverContext -> ApiRequest -> ReadPlanTree -> Either Error ReadPlanTree
 addFilters ctx ApiRequest{..} rReq =
-  foldr addFilterToNode (Right rReq) flts
+  foldr addFilterToNode (Right rReq) (flts ++ getFiltersFromLogicTree ++ getNullFiltersFromRelFilters)
   where
     QueryParams.QueryParams{..} = iQueryParams
     flts =
       case iAction of
-        ActDb (ActRelationRead _  _) -> qsFilters
-        ActDb (ActRoutine _ _)       -> qsFilters
-        _                            -> qsFiltersNotRoot
+        ActDb (ActRelationRead _  _) -> newFilter <$> qsFilters
+        ActDb (ActRoutine _ _)       -> newFilter <$> qsFilters
+        _                            -> newFilter <$> qsFiltersNotRoot
 
     addFilterToNode :: (EmbedPath, Filter) -> Either Error ReadPlanTree ->  Either Error ReadPlanTree
     addFilterToNode =
       updateNode (\flt (Node q@ReadPlan{from=fromTable, where_=lf} f) -> Node q{ReadPlan.where_=addFilterToLogicForest (resolveFilter ctx{qi=fromTable} flt) lf}  f)
 
+    newFilter :: (EmbedPath, Filter) -> (EmbedPath, Filter)
+    newFilter (ep, rf@(RelFilter rel _ _)) = (ep ++ [rel], rf)
+    newFilter flt = flt
+
+    getNullFiltersFromRelFilters :: [(EmbedPath, Filter)]
+    getNullFiltersFromRelFilters = concatMap (uncurry relToFlt) qsFilters
+
+    relToFlt :: EmbedPath -> Filter -> [(EmbedPath, Filter)]
+    relToFlt ep (RelFilter rel _ _) = [(ep, relEmbedPathToNotIsNull rel)]
+    relToFlt _ _ = []
+
+    getFiltersFromLogicTree :: [(EmbedPath, Filter)]
+    getFiltersFromLogicTree = concatMap (uncurry logicRelToFlt) qsLogic
+
+    logicRelToFlt :: EmbedPath -> LogicTree -> [(EmbedPath, Filter)]
+    logicRelToFlt ep (Stmnt rf@(RelFilter path _ _)) = [(ep ++ [path], rf)]
+    logicRelToFlt ep (Expr _ _ lstTree) = concatMap (logicRelToFlt ep) lstTree
+    logicRelToFlt _ _ = []
+
 addOrders :: ResolverContext -> ApiRequest -> ReadPlanTree -> Either Error ReadPlanTree
 addOrders ctx ApiRequest{..} rReq = foldr addOrderToNode (Right rReq) qsOrder
   where
@@ -950,11 +969,16 @@ addLogicTrees ctx ApiRequest{..} rReq =
     addLogicTreeToNode = updateNode (\t (Node q@ReadPlan{from=fromTable, where_=lf} f) -> Node q{ReadPlan.where_=resolveLogicTree ctx{qi=fromTable} t:lf} f)
 
 resolveLogicTree :: ResolverContext -> LogicTree -> CoercibleLogicTree
+resolveLogicTree ctx (Stmnt (RelFilter ep _ _)) = CoercibleStmnt $ resolveFilter ctx (relEmbedPathToNotIsNull ep)
 resolveLogicTree ctx (Stmnt flt) = CoercibleStmnt $ resolveFilter ctx flt
 resolveLogicTree ctx (Expr b op lts) = CoercibleExpr b op (map (resolveLogicTree ctx) lts)
 
 resolveFilter :: ResolverContext -> Filter -> CoercibleFilter
 resolveFilter ctx (Filter fld opExpr) = CoercibleFilter{field=resolveQueryInputField ctx fld opExpr, opExpr=opExpr}
+resolveFilter ctx (RelFilter _ fld opExpr) = CoercibleFilter{field=resolveQueryInputField ctx fld opExpr, opExpr=opExpr}
+
+relEmbedPathToNotIsNull :: FieldName -> Filter
+relEmbedPathToNotIsNull ep = Filter (ep, []) (OpExpr True (Is IsNull))
 
 -- Find a Node of the Tree and apply a function to it
 updateNode :: (a -> ReadPlanTree -> ReadPlanTree) -> (EmbedPath, a) -> Either Error ReadPlanTree -> Either Error ReadPlanTree

test/spec/Feature/Query/RelatedQueriesSpec.hs

@@ -378,3 +378,182 @@ spec = describe "related queries" $ do
         , matchHeaders = [ matchContentTypeJson
                          , "Content-Range" <:> "0-1/952" ]
         }
+
+  context "related conditions using the embed(column) syntax" $ do
+    it "works on a many-to-one relationship" $ do
+      get "/projects?select=name,clients()&clients(name)=eq.Microsoft" `shouldRespondWith`
+        [json|[
+          {"name":"Windows 7"},
+          {"name":"Windows 10"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+      get "/projects?select=name,computed_clients()&computed_clients(name)=eq.Apple" `shouldRespondWith`
+        [json|[
+          {"name":"IOS"},
+          {"name":"OSX"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+
+    it "works on a one-to-many relationship" $ do
+      get "/entities?select=name,child_entities()&child_entities(name)=like.child*" `shouldRespondWith`
+        [json|[
+          {"name":"entity 1"},
+          {"name":"entity 2"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+      get "/entities?select=name,child_entities()&child_entities(name)=like(any).{*1,*2}" `shouldRespondWith`
+        [json|[
+          {"name":"entity 1"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+
+    it "works on a many-to-many relationship" $ do
+      get "/users?select=name,tasks()&tasks(id)=eq.1" `shouldRespondWith`
+        [json|[
+          {"name":"Angela Martin"},
+          {"name":"Dwight Schrute"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+      get "/users?select=name,tasks()&tasks(id)=eq.7" `shouldRespondWith`
+        [json|[
+          {"name":"Michael Scott"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+{-- TODO(draft): make nesting work
+    it "works on nested embeds" $ do
+      get "/entities?select=name,child_entities(name,grandchild_entities())&child_entities(grandchild_entities(name))=like.*1" `shouldRespondWith`
+        [json|[
+          {"name":"entity 1","child_entities":[{"name":"child entity 1"}, {"name":"child entity 2"}]}]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+--}
+    it "can do an or across embeds" $
+      get "/client?select=*,clientinfo(),contact()&or=(clientinfo(other).like.*Main*,contact(name).like.*Tabby*)" `shouldRespondWith`
+        [json|[
+          {"id":1,"name":"Walmart"},
+          {"id":2,"name":"Target"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+
+    it "works when the embedding uses the column name" $ do
+      get "/projects?select=name,c_id:client_id,client_id(name)&client_id(name)=like.Apple" `shouldRespondWith`
+        [json|[
+          {"name":"IOS","c_id":2,"client_id":{"name":"Apple"}},
+          {"name":"OSX","c_id":2,"client_id":{"name":"Apple"}}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+      get "/projects?select=name,client_id(name)&client_id(name)=like.Apple" `shouldRespondWith`
+        [json|[
+          {"name":"IOS","client_id":{"name":"Apple"}},
+          {"name":"OSX","client_id":{"name":"Apple"}}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+
+    -- "?table=not.is.null" does a "table IS DISTINCT FROM NULL" instead of a "table IS NOT NULL"
+    -- https://github.com/PostgREST/postgrest/issues/2800#issuecomment-1720315818
+    it "embeds verifying that the entire target table row is not null" $ do
+      get "/table_b?select=name,table_a(name)&table_a(id)=eq(any).{1,2}" `shouldRespondWith`
+        [json|[
+          {"name":"Test 1","table_a":{"name":"Not null 1"}},
+          {"name":"Test 2","table_a":{"name":null}}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [matchContentTypeJson]
+        }
+
+    it "works with count=exact" $ do
+      request methodGet "/projects?select=name,clients(name)&clients(id)=gt.0"
+        [("Prefer", "count=exact")] ""
+       `shouldRespondWith`
+        [json|[
+          {"name":"Windows 7", "clients":{"name":"Microsoft"}},
+          {"name":"Windows 10", "clients":{"name":"Microsoft"}},
+          {"name":"IOS", "clients":{"name":"Apple"}},
+          {"name":"OSX", "clients":{"name":"Apple"}}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-3/4" ]
+        }
+      request methodGet "/client?select=*,clientinfo(),contact()&or=(clientinfo(other).ilike.*main*,contact(name).ilike.*tabby*)"
+        [("Prefer", "count=exact")] ""
+       `shouldRespondWith`
+        [json|[
+          {"id":1,"name":"Walmart"},
+          {"id":2,"name":"Target"}
+        ]|]
+        { matchStatus  = 200
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-1/2" ]
+        }
+
+    it "works with count=planned" $ do
+      request methodGet "/projects?select=name,clients(name)&clients(id)=gt.0"
+        [("Prefer", "count=planned")] ""
+       `shouldRespondWith`
+        [json|[
+          {"name":"Windows 7", "clients":{"name":"Microsoft"}},
+          {"name":"Windows 10", "clients":{"name":"Microsoft"}},
+          {"name":"IOS", "clients":{"name":"Apple"}},
+          {"name":"OSX", "clients":{"name":"Apple"}}
+        ]|]
+        { matchStatus  = 206
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-3/400" ]
+        }
+      request methodGet "/client?select=*,clientinfo(),contact()&or=(clientinfo(other).ilike.*main*,contact(name).ilike.*tabby*)"
+        [("Prefer", "count=planned")] ""
+       `shouldRespondWith`
+        [json|[
+          {"id":1,"name":"Walmart"},
+          {"id":2,"name":"Target"}
+        ]|]
+        { matchStatus  = 206
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-1/952" ]
+        }
+
+    it "works with count=estimated" $ do
+      request methodGet "/projects?select=name,clients(name)&clients(id)=gt.0"
+        [("Prefer", "count=estimated")] ""
+       `shouldRespondWith`
+        [json|[
+          {"name":"Windows 7", "clients":{"name":"Microsoft"}},
+          {"name":"Windows 10", "clients":{"name":"Microsoft"}},
+          {"name":"IOS", "clients":{"name":"Apple"}},
+          {"name":"OSX", "clients":{"name":"Apple"}}
+        ]|]
+        { matchStatus  = 206
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-3/400" ]
+        }
+      request methodGet "/client?select=*,clientinfo(),contact()&or=(clientinfo(other).ilike.*main*,contact(name).ilike.*tabby*)"
+        [("Prefer", "count=estimated")] ""
+       `shouldRespondWith`
+        [json|[
+          {"id":1,"name":"Walmart"},
+          {"id":2,"name":"Target"}
+        ]|]
+        { matchStatus  = 206
+        , matchHeaders = [ matchContentTypeJson
+                         , "Content-Range" <:> "0-1/952" ]
+        }