6 -- |Utility functions used internally in the Lucu httpd. These
7 -- functions may be useful too for something else.
8 module Network.HTTP.Lucu.Utils
12 , parseWWWFormURLEncoded
17 import Blaze.ByteString.Builder.ByteString as B
18 import Blaze.Text.Int as BT
20 import Data.Ascii (Ascii, AsciiBuilder)
21 import qualified Data.Ascii as A
22 import Data.ByteString (ByteString)
23 import qualified Data.ByteString.Char8 as BS
24 import Data.List hiding (last)
25 import Data.Monoid.Unicode
26 import Data.Text (Text)
27 import Data.Text.Encoding as T
29 import Prelude hiding (last)
30 import Prelude.Unicode
32 -- |> splitBy (== ':') "ab:c:def"
33 -- > ==> ["ab", "c", "def"]
34 splitBy ∷ (a → Bool) → [a] → [[a]]
36 = case break isSep src
37 of (last , [] ) → [last]
38 (first, _sep:rest) → first : splitBy isSep rest
40 -- |> joinWith ":" ["ab", "c", "def"]
42 joinWith ∷ Ascii → [AsciiBuilder] → AsciiBuilder
43 {-# INLINEABLE joinWith #-}
44 joinWith sep = flip go (∅)
46 go ∷ [AsciiBuilder] → AsciiBuilder → AsciiBuilder
50 go (x:xs) ab = go xs (ab ⊕ A.toAsciiBuilder sep ⊕ x)
56 -- > ==> "\"ab\\\"c\""
57 quoteStr ∷ Ascii → AsciiBuilder
58 quoteStr str = A.toAsciiBuilder "\"" ⊕
59 go (A.toByteString str) (∅) ⊕
62 go ∷ BS.ByteString → AsciiBuilder → AsciiBuilder
64 = case BS.break (≡ '"') bs of
66 | BS.null y → ab ⊕ b2ab x
67 | otherwise → go (BS.tail y) (ab ⊕ b2ab x
68 ⊕ A.toAsciiBuilder "\\\"")
70 b2ab ∷ BS.ByteString → AsciiBuilder
71 b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
73 -- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
74 -- > ==> [("aaa", "bbb"), ("ccc", "ddd")]
75 parseWWWFormURLEncoded ∷ Ascii → [(ByteString, ByteString)]
76 parseWWWFormURLEncoded src
77 -- THINKME: We could gain some performance by using attoparsec
80 | otherwise = do pairStr ← splitBy (\ c → c ≡ ';' ∨ c ≡ '&') (A.toString src)
81 let (key, value) = break (≡ '=') pairStr
83 , unescape $ case value of
88 unescape ∷ String → ByteString
89 unescape = BS.pack ∘ unEscapeString ∘ map plusToSpace
91 plusToSpace ∷ Char → Char
95 -- |> splitPathInfo "http://example.com/foo/bar"
96 -- > ==> ["foo", "bar"]
97 splitPathInfo ∷ URI → [Text]
99 = let reqPathStr = uriPath uri
100 reqPath = [unEscapeString x | x ← splitBy (≡ '/') reqPathStr, (¬) (null x)]
102 map (T.decodeUtf8 ∘ BS.pack) reqPath
106 show3 ∷ Integral n ⇒ n → AsciiBuilder
107 {-# INLINEABLE show3 #-}
108 show3 = A.unsafeFromBuilder ∘ go
110 go i | i ≥ 0 ∧ i < 10 = B.fromByteString "00" ⊕ BT.digit i
111 | i ≥ 0 ∧ i < 100 = B.fromByteString "0" ⊕ BT.integral i
112 | i ≥ 0 ∧ i < 1000 = BT.integral i
113 | otherwise = error ("show3: the integer i must satisfy 0 <= i < 1000: " ⧺ show i)