X-Git-Url: http://git.cielonegro.org/gitweb.cgi?a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FETag.hs;h=056f14fa4c8f847512abd93c1cf4af62de25006d;hb=50a37a0b36af70046b57472d314195bd8d99fed8;hp=86dd429e265100b8318716679ebfd4d0554120b0;hpb=c6b11025d1f81c668e9995e856b7bb34175230d3;p=Lucu.git diff --git a/Network/HTTP/Lucu/ETag.hs b/Network/HTTP/Lucu/ETag.hs index 86dd429..056f14f 100644 --- a/Network/HTTP/Lucu/ETag.hs +++ b/Network/HTTP/Lucu/ETag.hs @@ -1,54 +1,70 @@ +{-# LANGUAGE + OverloadedStrings + , UnicodeSyntax + #-} +{-# OPTIONS_HADDOCK prune #-} + +-- |Manipulation of entity tags. module Network.HTTP.Lucu.ETag - ( ETag - , mkETag -- Bool -> String -> ETag - , strongETag -- String -> ETag - , weakETag -- String -> ETag - , eTagP -- Parser ETag - , eTagListP -- Parser [ETag] - ) - where + ( ETag(..) -import Control.Monad -import Network.HTTP.Lucu.Parser -import Network.HTTP.Lucu.Parser.Http -import Network.HTTP.Lucu.Utils + , printETag + , strongETag + , weakETag + , eTagP + , eTagListP + ) + where +import Control.Monad +import Control.Monad.Unicode +import Data.Ascii (Ascii) +import qualified Data.Ascii as A +import Data.Attoparsec.Char8 +import Data.Monoid.Unicode +import Network.HTTP.Lucu.Parser.Http hiding (token) +import Network.HTTP.Lucu.Utils +-- |An entity tag is made of a weakness flag and a opaque string. data ETag = ETag { - etagIsWeak :: Bool - , etagToken :: String - } deriving (Eq) - -instance Show ETag where - show (ETag isWeak token) = (if isWeak then - "W/" - else - "") - ++ - quoteStr token + -- |The weakness flag. Weak tags looks like W\/\"blahblah\" and + -- strong tags are like \"blahblah\". + etagIsWeak ∷ !Bool + -- |An opaque string. Only characters from 0x20 (sp) to 0x7e (~) + -- are allowed. + , etagToken ∷ !Ascii + } deriving (Eq, Show) +-- |Convert an 'ETag' to 'Ascii'. +printETag ∷ ETag → Ascii +printETag et + = A.fromAsciiBuilder $ + ( ( if etagIsWeak et then + A.toAsciiBuilder "W/" + else + (∅) + ) + ⊕ + quoteStr (etagToken et) ) -mkETag :: Bool -> String -> ETag -mkETag = ETag - - -strongETag :: String -> ETag +-- |This is equivalent to @'ETag' 'Prelude.False'@. If you want to +-- generate an ETag from a file, try using +-- 'Network.HTTP.Lucu.StaticFile.generateETagFromFile'. +strongETag ∷ Ascii → ETag strongETag = ETag False - -weakETag :: String -> ETag +-- |This is equivalent to @'ETag' 'Prelude.True'@. +weakETag ∷ Ascii → ETag weakETag = ETag True +eTagP ∷ Parser ETag +eTagP = try $ + do isWeak ← option False (string "W/" ≫ return True) + str ← quotedStr + return $ ETag isWeak str -eTagP :: Parser ETag -eTagP = do isWeak <- option False (string "W/" >> return True) - str <- quotedStr - return $ mkETag isWeak str - - -eTagListP :: Parser [ETag] -eTagListP = allowEOF - $ do xs <- listOf eTagP - when (null xs) - $ fail "" - return xs +eTagListP ∷ Parser [ETag] +eTagListP = do xs ← listOf eTagP + when (null xs) $ + fail "empty list of ETags" + return xs