fix #453 by sending the request to the db (instead of using the cached data)

src/PostgREST/App.hs

@@ -178,7 +178,7 @@ app dbStructure conf reqBody req =
         else return notFound
 
     (ActionRead, TargetRoot, Nothing) -> do
-      body <- encode <$> accessibleTables (filter ((== cs schema) . tableSchema) (dbTables dbStructure))
+      body <- encode <$> accessibleTables (cs schema)
       return $ responseLBS status200 [jsonH] $ cs body
 
     (ActionUnknown _, _, _) -> return notFound

src/PostgREST/DbStructure.hs

@@ -71,25 +71,33 @@ doesProcReturnJWT = doesProc [H.stmt|
       AND    pg_catalog.pg_get_function_result(p.oid) like '%jwt_claims'
     |]
 
-accessibleTables :: [Table] -> H.Tx P.Postgres s [Table]
-accessibleTables allTabs = do
-  accessible <- H.listEx $ [H.stmt|
-      SELECT
-        n.nspname AS table_schema,
-        c.relname AS table_name
-      FROM pg_class c
-      JOIN pg_namespace n ON n.oid = c.relnamespace
-      WHERE
-        c.relkind IN ('v','r','m') AND
-        n.nspname NOT IN ('pg_catalog', 'information_schema') AND (
-          pg_has_role(c.relowner, 'USAGE'::text) OR
-          has_table_privilege(c.oid, 'SELECT, INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER'::text) OR
-          has_any_column_privilege(c.oid, 'SELECT, INSERT, UPDATE, REFERENCES'::text)
+accessibleTables :: Schema -> H.Tx P.Postgres s [Table]
+accessibleTables schema = do
+  rows <- H.listEx $
+    [H.stmt|
+      select
+        n.nspname as table_schema,
+        relname as table_name,
+        c.relkind = 'r' or (c.relkind IN ('v', 'f')) and (pg_relation_is_updatable(c.oid::regclass, false) & 8) = 8
+        or (exists (
+           select 1
+           from pg_trigger
+           where pg_trigger.tgrelid = c.oid and (pg_trigger.tgtype::integer & 69) = 69)
+        ) as insertable
+      from
+        pg_class c
+        join pg_namespace n on n.oid = c.relnamespace
+      where
+        c.relkind in ('v', 'r', 'm')
+        and n.nspname = ?
+        and (
+          pg_has_role(c.relowner, 'USAGE'::text)
+          or has_table_privilege(c.oid, 'SELECT, INSERT, UPDATE, DELETE, TRUNCATE, REFERENCES, TRIGGER'::text)
+          or has_any_column_privilege(c.oid, 'SELECT, INSERT, UPDATE, REFERENCES'::text)
         )
-      ORDER BY table_schema, table_name
-    |]
-  let isAccessible table = isJust $ find (\(s,n) -> tableSchema table == s && tableName table == n) accessible
-  return $ filter isAccessible allTabs
+      order by relname
+    |] schema
+  return $ map tableFromRow rows
 
 synonymousColumns :: [(Column,Column)] -> [Column] -> [[Column]]
 synonymousColumns allSyns cols = synCols'