Reimplement MultipartForm

[Lucu.git] / Network / HTTP / Lucu / Utils.hs

diff --git a/Network/HTTP/Lucu/Utils.hs b/Network/HTTP/Lucu/Utils.hs
index 58da6f50c2612ac1e64e4d8366e17dfa21712f50..3d38b8b3aec36c9dff990cb4c7e66d05995ad27e 100644 (file)
--- a/Network/HTTP/Lucu/Utils.hs
+++ b/Network/HTTP/Lucu/Utils.hs
@@ -1,51 +1,100 @@
+{-# LANGUAGE
+    OverloadedStrings
+  , UnicodeSyntax
+  #-}
+-- |Utility functions used internally in the Lucu httpd. These
+-- functions may be useful too for something else.
 module Network.HTTP.Lucu.Utils
-    ( splitBy      -- (a -> Bool) -> [a] -> [[a]]
-    , joinWith     -- [a] -> [[a]] -> [a]
-    , trim         -- (a -> Bool) -> [a] -> [a]
-    , noCaseEq     -- String -> String -> Bool
-    , isWhiteSpace -- Char -> Bool
-    , quoteStr     -- String -> String
+    ( splitBy
+    , quoteStr
+    , parseWWWFormURLEncoded
+    , splitPathInfo
+    , show3
     )
     where
+import Blaze.ByteString.Builder.ByteString as B
+import Blaze.Text.Int as BT
+import Control.Monad
+import Data.Ascii (Ascii, AsciiBuilder)
+import qualified Data.Ascii as A
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as BS
+import Data.List hiding (last)
+import Data.Monoid.Unicode
+import Network.URI
+import Prelude hiding (last)
+import Prelude.Unicode
 
-import Control.Monad.Trans
-import Data.Char
-import Data.List
-import Foreign
-import Foreign.C
+-- |> splitBy (== ':') "ab:c:def"
+--  > ==> ["ab", "c", "def"]
+splitBy ∷ (a → Bool) → [a] → [[a]]
+{-# INLINEABLE splitBy #-}
+splitBy isSep src
+    = case break isSep src of
+        (last , []       ) → [last]
+        (first, _sep:rest) → first : splitBy isSep rest
 
-
-splitBy :: (a -> Bool) -> [a] -> [[a]]
-splitBy isSeparator src
-    = case break isSeparator src
-      of (last , []      ) -> last  : []
-         (first, sep:rest) -> first : splitBy isSeparator rest
-
-
-joinWith :: [a] -> [[a]] -> [a]
-joinWith separator xs
-    = foldr (++) [] $ intersperse separator xs
-
-
-trim :: (a -> Bool) -> [a] -> [a]
-trim p = trimTail . trimHead
+-- |> quoteStr "abc"
+--  > ==> "\"abc\""
+--
+--  > quoteStr "ab\"c"
+--  > ==> "\"ab\\\"c\""
+quoteStr ∷ Ascii → AsciiBuilder
+quoteStr str = A.toAsciiBuilder "\"" ⊕
+               go (A.toByteString str) (∅) ⊕
+               A.toAsciiBuilder "\""
     where
-      trimHead = dropWhile p
-      trimTail = reverse . trimHead . reverse
-
+      go ∷ BS.ByteString → AsciiBuilder → AsciiBuilder
+      go bs ab
+          = case BS.break (≡ '"') bs of
+              (x, y)
+                  | BS.null y → ab ⊕ b2ab x
+                  | otherwise → go (BS.tail y) (ab ⊕ b2ab x
+                                                   ⊕ A.toAsciiBuilder "\\\"")
 
-noCaseEq :: String -> String -> Bool
-noCaseEq a b
-    = (map toLower a) == (map toLower b)
+      b2ab ∷ BS.ByteString → AsciiBuilder
+      b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
 
+-- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
+--  > ==> [("aaa", "bbb"), ("ccc", "ddd")]
+parseWWWFormURLEncoded ∷ Ascii → [(ByteString, ByteString)]
+parseWWWFormURLEncoded src
+    -- THINKME: We could gain some performance by using attoparsec
+    -- here.
+    | src ≡ ""  = []
+    | otherwise = do pairStr ← splitBy (\ c → c ≡ ';' ∨ c ≡ '&') (A.toString src)
+                     let (key, value) = break (≡ '=') pairStr
+                     return ( unescape key
+                            , unescape $ case value of
+                                           ('=':val) → val
+                                           val       → val
+                            )
+    where
+      unescape ∷ String → ByteString
+      unescape = BS.pack ∘ unEscapeString ∘ map plusToSpace
 
-isWhiteSpace :: Char -> Bool
-isWhiteSpace = flip elem " \t\r\n"
+      plusToSpace ∷ Char → Char
+      plusToSpace '+' = ' '
+      plusToSpace c   = c
 
+-- |> splitPathInfo "http://example.com/foo/bar"
+--  > ==> ["foo", "bar"]
+splitPathInfo ∷ URI → [ByteString]
+splitPathInfo uri
+    = let reqPathStr = uriPath uri
+          reqPath    = [unEscapeString x | x ← splitBy (≡ '/') reqPathStr, (¬) (null x)]
+      in
+        map BS.pack reqPath
 
-quoteStr :: String -> String
-quoteStr str = foldr (++) "" (["\""] ++ map quote str ++ ["\""])
+-- |> show3 5
+--  > ==> "005"
+show3 ∷ Integral n ⇒ n → AsciiBuilder
+{-# INLINEABLE show3 #-}
+show3 = A.unsafeFromBuilder ∘ go
     where
-      quote :: Char -> String
-      quote '"' = "\\\""
-      quote c   = [c]
\ No newline at end of file
+      go i | i ≥ 0 ∧ i < 10   = B.fromByteString "00" ⊕ BT.digit    i
+           | i ≥ 0 ∧ i < 100  = B.fromByteString "0"  ⊕ BT.integral i
+           | i ≥ 0 ∧ i < 1000 =                         BT.integral i
+           | otherwise        = error ("show3: the integer i must satisfy 0 <= i < 1000: " ⧺ show i)
+-- FIXME: Drop this function as soon as possible, to eliminate the
+-- dependency on blaze-textual.