StatusCode is now a type class, not an algebraic data type.

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

diff --git a/Network/HTTP/Lucu/Utils.hs b/Network/HTTP/Lucu/Utils.hs
index dbc65ac17ad8a52f553af26e5506a33df9aab137..d6e571dd0fcf3ab0a2ad30c4cd1ac8188516d96c 100644 (file)
--- a/Network/HTTP/Lucu/Utils.hs
+++ b/Network/HTTP/Lucu/Utils.hs
@@ -1,74 +1,77 @@
 {-# LANGUAGE
-    BangPatterns
+    OverloadedStrings
+  , TemplateHaskell
   , UnicodeSyntax
   #-}
 -- |Utility functions used internally in the Lucu httpd. These
 -- functions may be useful too for something else.
 module Network.HTTP.Lucu.Utils
     ( splitBy
-    , joinWith
-    , trim
-    , isWhiteSpace
     , quoteStr
     , parseWWWFormURLEncoded
+    , splitPathInfo
+    , trim
+    , liftCIAscii
+    , liftText
+    , liftMap
     )
     where
 import Control.Monad
-import Data.List     hiding (last)
+import Data.Ascii (Ascii, CIAscii, AsciiBuilder)
+import qualified Data.Ascii as A
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as BS
+import Data.Char
+import Data.List hiding (last)
+import Data.Map (Map)
+import qualified Data.Map as M
+import Data.Monoid.Unicode
+import Data.Text (Text)
+import qualified Data.Text as T
+import Language.Haskell.TH.Lib
+import Language.Haskell.TH.Syntax
 import Network.URI
-import Prelude       hiding (last)
+import Prelude hiding (last)
 import Prelude.Unicode
 
--- |> splitBy (== ':') "ab:c:def"
---  > ==> ["ab", "c", "def"]
-splitBy :: (a -> Bool) -> [a] -> [[a]]
+-- |>>> 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
-
--- |> joinWith ":" ["ab", "c", "def"]
---  > ==> "ab:c:def"
-joinWith :: [a] -> [[a]] -> [a]
-joinWith = (join .) . intersperse
-
--- |> trim (== '_') "__ab_c__def___"
---  > ==> "ab_c__def"
-trim :: (a -> Bool) -> [a] -> [a]
-trim !p = trimTail . trimHead
-    where
-      trimHead = dropWhile p
-      trimTail = reverse . trimHead . reverse
-
--- |@'isWhiteSpace' c@ is 'Prelude.True' iff c is one of SP, HT, CR
--- and LF.
-isWhiteSpace :: Char -> Bool
-isWhiteSpace ' '  = True
-isWhiteSpace '\t' = True
-isWhiteSpace '\r' = True
-isWhiteSpace '\n' = True
-isWhiteSpace _    = False
-{-# INLINE isWhiteSpace #-}
+    = case break isSep src of
+        (last , []       ) → [last]
+        (first, _sep:rest) → first : splitBy isSep rest
 
--- |> quoteStr "abc"
---  > ==> "\"abc\""
+-- |>>> quoteStr "abc"
+-- "\"abc\""
 --
---  > quoteStr "ab\"c"
---  > ==> "\"ab\\\"c\""
-quoteStr :: String -> String
-quoteStr !str = concat (["\""] ++ map quote str ++ ["\""])
+-- >>> quoteStr "ab\"c"
+-- "\"ab\\\"c\""
+quoteStr ∷ Ascii → AsciiBuilder
+quoteStr str = A.toAsciiBuilder "\"" ⊕
+               go (A.toByteString str) (∅) ⊕
+               A.toAsciiBuilder "\""
     where
-      quote :: Char -> String
-      quote '"' = "\\\""
-      quote c   = [c]
+      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 "\\\"")
 
+      b2ab ∷ BS.ByteString → AsciiBuilder
+      b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
 
--- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
---  > ==> [("aaa", "bbb"), ("ccc", "ddd")]
-parseWWWFormURLEncoded ∷ String → [(String, String)]
+-- |>>> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
+-- [("aaa", "bbb"), ("ccc", "ddd")]
+parseWWWFormURLEncoded ∷ Ascii → [(ByteString, ByteString)]
 parseWWWFormURLEncoded src
-    | null src  = []
-    | otherwise = do pairStr ← splitBy (\ c → c ≡ ';' ∨ c ≡ '&') 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
@@ -76,9 +79,47 @@ parseWWWFormURLEncoded src
                                            val       → val
                             )
     where
-      unescape ∷ String → String
-      unescape = unEscapeString ∘ map plusToSpace
+      unescape ∷ String → ByteString
+      unescape = BS.pack ∘ unEscapeString ∘ map plusToSpace
 
       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
+
+-- |>>> trim "  ab c d "
+-- "ab c d"
+trim ∷ String → String
+trim = reverse ∘ f ∘ reverse ∘ f
+    where
+      f = dropWhile isSpace
+
+-- |Convert a 'CIAscii' to an 'Exp' representing it as a literal.
+liftCIAscii ∷ CIAscii → Q Exp
+liftCIAscii a = [| A.toCIAscii (A.unsafeFromString $(strLit a)) |]
+    where
+      strLit ∷ CIAscii → Q Exp
+      strLit = liftString ∘ A.toString ∘ A.fromCIAscii
+
+-- |Convert a 'Text' to an 'Exp' representing it as a literal.
+liftText ∷ Text → Q Exp
+liftText t = [| T.pack $(strLit t) |]
+    where
+      strLit ∷ Text → Q Exp
+      strLit = liftString ∘ T.unpack
+
+-- |Convert an arbitrary 'Map' to an 'Exp' representing it as a
+-- literal, using a given key lifter and a value lifter.
+liftMap ∷ Eq k ⇒ (k → Q Exp) → (v → Q Exp) → Map k v → Q Exp
+liftMap liftK liftV m = [| M.fromAscList $(liftPairs $ M.toAscList m) |]
+    where
+      liftPairs       = listE ∘ map liftPair
+      liftPair (k, v) = tupE [liftK k, liftV v]