[Fencommits] fenserve: prepare for using RDF: use Nodes instead of BlockIds to identify directories, so that we can have blk:...#dir

[Benja Fallenstein]

Sun Mar 18 15:47:56 EET 2007  Benja Fallenstein <benja.fallenstein at gmail.com>
  * prepare for using RDF: use Nodes instead of BlockIds to identify directories, so that we can have blk:...#dir
diff -rN -u old-fenserve/FenServe.hs new-fenserve/FenServe.hs
--- old-fenserve/FenServe.hs	2007-03-22 19:49:20.000000000 +0200
+++ new-fenserve/FenServe.hs	2007-03-22 19:49:20.000000000 +0200
@@ -55,7 +55,9 @@
 fs_language        = IRI "http://fenfire.org/2007/fenserve#language"
 
 rget :: Node -> Node -> Graph -> Node
-rget p s g = fromJust $ getOne g s p Pos
+rget p s g = fromMaybe (error $ "FenServe.rget: not found: " ++ show s
+                             ++ " " ++ show p)
+                       (getOne g s p Pos)
 
 data Entry = DirEntry { entryName :: String, entrySubdir :: Node }
            | FileEntry { entryName :: String, entryRepr :: Node } deriving (Show, Read)
@@ -63,9 +65,10 @@
 data Directory = Dir { dirNode :: Node, dirEntries :: [Entry] } deriving (Show, Read)
 
 emptyState :: Ptr
-emptyState = runStormIO (writeBlock (Dir (IRI "#dir") [])) Map.empty
+emptyState = runStormIO (liftM bIRI $ writeBlock (Dir (IRI "#dir") []))
+                        Map.empty
 
-type Ptr = (BlockId, Pool)
+type Ptr = (Node, Pool)
 
 instance ToRDF Directory where
     toRDF (Dir node entries) = do
@@ -141,16 +144,16 @@
 bID :: Node -> BlockId
 bID (IRI ('b':'l':'k':':':s)) = BlockId $ takeWhile (/= '#') s
   
-readGraph :: BlockId -> StormIO Graph
-readGraph bid = liftM (setGraphURI $ bURI bid) $ readBlock bid
+readGraph :: Node -> StormIO Graph
+readGraph gNode = liftM (setGraphURI $ nodeStr gNode) $ readBlock (bID gNode)
 
-getURI :: [String] -> BlockId -> StormIO ByteString
-getURI [x] bid = readBlock bid >>= f . dirEntries where
+getURI :: [String] -> Node -> StormIO ByteString
+getURI [x] dir = readBlock (bID dir) >>= f . dirEntries where
     f (FileEntry n r : _ ) | n == x = getBlock (bID r)
     f (_             : es) = f es
     f []                   = return $ toUTF $ "not found: " ++ x
-getURI (x:xs) bid = readBlock bid >>= f . dirEntries where
-    f (DirEntry n sub : _ ) | n == x = getURI xs (bID sub)
+getURI (x:xs) dir = readBlock (bID dir) >>= f . dirEntries where
+    f (DirEntry n sub : _ ) | n == x = getURI xs sub
     f (_              : es) = f es
     f []                    = return $ toUTF $ "dir not found: " ++ x
 
@@ -161,20 +164,20 @@
                                 in writeGraph graph' pool
 -}
 
-updateData :: (Read a, Show a) => EndoM StormIO a -> EndoM StormIO BlockId
-updateData f bid = writeBlock =<< f =<< readBlock bid
+updateData :: (Read a, Show a) => EndoM StormIO a -> EndoM StormIO Node
+updateData f node = return . bIRI =<< writeBlock =<< f =<< readBlock (bID node)
 
-putURI :: [String] -> ByteString -> BlockId -> StormIO BlockId
-putURI path s bid = do rid <- addBlock s; putURI' path (bIRI rid) bid where
-  putURI' [x] r bid = do updateData f' bid where
+putURI :: [String] -> ByteString -> Node -> StormIO Node
+putURI path s dir = do rid <- addBlock s; putURI' path (bIRI rid) dir where
+  putURI' [x] r dir = do updateData f' dir where
     f' (Dir n entries) = return $ Dir n (f entries)
     f (FileEntry n _ : es) | n == x = FileEntry n r : es
     f (e             : es) = e : f es
     f []                   = [FileEntry x r]
-  putURI' (x:xs) r bid = updateData f' bid where
-    recurse sub = do sub' <- putURI' xs r sub; return [DirEntry x (bIRI sub')]
+  putURI' (x:xs) r dir = updateData f' dir where
+    recurse sub = do sub' <- putURI' xs r sub; return [DirEntry x sub']
     f' (Dir n entries) = do es' <- f entries; return (Dir n es')
-    f (DirEntry n sub : es) | n == x = liftM (++es) (recurse $ bID sub)
+    f (DirEntry n sub : es) | n == x = liftM (++es) (recurse sub)
     f (e              : es) = do es' <- f es; return (e:es')
     f []                    = recurse (fst $ emptyState)