{-# LANGUAGE
- BangPatterns
+ DeriveDataTypeable
+ , GeneralizedNewtypeDeriving
+ , MultiParamTypeClasses
+ , TemplateHaskell
, UnicodeSyntax
+ , ViewPatterns
#-}
--- |MIME Type guessing by a file extension. This is a poor man's way
--- of guessing MIME Types. It is simple and fast.
+-- |Guessing MIME Types by file extensions. It's not always accurate
+-- but simple and fast.
--
-- In general you don't have to use this module directly.
module Network.HTTP.Lucu.MIMEType.Guess
- ( ExtMap
+ ( ExtMap(..)
+ , extMap
, guessTypeByFileName
-
- , parseExtMapFile
- , serializeExtMap
)
where
import Control.Applicative
-import qualified Data.Ascii as A
-import Data.Attoparsec.Char8 as P
+import Data.Attoparsec.Char8
import qualified Data.Attoparsec.Lazy as LP
-import qualified Data.ByteString.Lazy.Char8 as B
+import qualified Data.ByteString.Lazy.Char8 as Lazy
+import Data.Convertible.Base
+import Data.Convertible.Instances.Text ()
+import Data.Default
import qualified Data.Map as M
import Data.Map (Map)
-import Data.Maybe
+import Data.Typeable
+import Data.List
+import Data.Monoid
+import Data.Monoid.Unicode
import Data.Text (Text)
-import qualified Data.Text as T
import Data.Text.Encoding
-import Language.Haskell.Pretty
-import Language.Haskell.Syntax
+import Language.Haskell.TH.Syntax
+import Language.Haskell.TH.Quote
import Network.HTTP.Lucu.MIMEType
+import Network.HTTP.Lucu.OrphanInstances ()
+import Network.HTTP.Lucu.Parser
import Prelude.Unicode
import System.FilePath
--- |'Map' from extension to 'MIMEType'.
-type ExtMap = Map Text MIMEType
-
--- |Guess the MIME Type of file.
-guessTypeByFileName ∷ ExtMap → FilePath → Maybe MIMEType
-guessTypeByFileName !extMap !fpath
- = let ext = T.pack $ takeExtension fpath
- in
- M.lookup ext extMap
+-- |A 'Map' from file extensions to 'MIMEType's.
+newtype ExtMap
+ = ExtMap (Map Text MIMEType)
+ deriving (Eq, Show, Read, Monoid, Typeable)
--- |Read an Apache mime.types and parse it.
-parseExtMapFile ∷ FilePath → IO ExtMap
-parseExtMapFile fpath
- = do file ← B.readFile fpath
- case LP.parse extMapP file of
- LP.Done _ xs → return $ compile xs
- LP.Fail _ _ e → fail ("Failed to parse: " ⧺ fpath ⧺ ": " ⧺ e)
+instance Lift ExtMap where
+ lift (ExtMap m) = [| ExtMap $(lift m) |]
-extMapP ∷ Parser [ (MIMEType, [Text]) ]
-extMapP = do xs ← P.many (comment <|> validLine <|> emptyLine)
- endOfInput
- return $ catMaybes xs
+-- |'QuasiQuoter' for 'ExtMap' reading Apache @mime.types@.
+--
+-- @
+-- m :: 'ExtMap'
+-- m = ['extMap'|
+-- # MIME Type Extensions
+-- application/xhtml+xml xhtml
+-- image/jpeg jpeg jpg
+-- image/png png
+-- image/svg+xml svg
+-- text/html html
+-- text/plain txt
+-- |]
+-- @
+extMap ∷ QuasiQuoter
+extMap = QuasiQuoter {
+ quoteExp = lift ∘ parseExtMap ∘ Lazy.pack
+ , quotePat = const unsupported
+ , quoteType = const unsupported
+ , quoteDec = const unsupported
+ }
where
- isSpc ∷ Char → Bool
- isSpc c = c ≡ '\x20' ∨ c ≡ '\x09'
+ parseExtMap ∷ Lazy.ByteString → ExtMap
+ parseExtMap = convertUnsafe
- comment ∷ Parser (Maybe (MIMEType, [Text]))
- comment = try $
- do skipWhile isSpc
- _ ← char '#'
- skipWhile (≢ '\x0A')
- return Nothing
+ unsupported ∷ Monad m ⇒ m α
+ unsupported = fail "Unsupported usage of extMap quasi-quoter."
- validLine ∷ Parser (Maybe (MIMEType, [Text]))
- validLine = try $
- do skipWhile isSpc
- mime ← mimeTypeP
- skipWhile isSpc
- exts ← sepBy extP (skipWhile isSpc)
- return $ Just (mime, exts)
+instance ConvertAttempt Lazy.ByteString ExtMap where
+ convertAttempt src
+ = case LP.parse pairs src of
+ LP.Fail _ eCtx e
+ → fail $ "Unparsable extension map: "
+ ⊕ intercalate ", " eCtx
+ ⊕ ": "
+ ⊕ e
+ LP.Done _ xs
+ → case compile xs of
+ Right m → return $ ExtMap m
+ Left e → fail $ "Duplicate extension: " ⊕ show e
+ where
+ pairs ∷ Parser [(MIMEType, [Text])]
+ pairs = do skipMany linebreak
+ xs ← sepBy pair (skipMany1 linebreak)
+ skipMany linebreak
+ endOfInput
+ return xs
+ <?>
+ "pairs"
- extP ∷ Parser Text
- extP = decodeUtf8 <$> takeWhile1 (\c → (¬) (isSpc c ∨ c ≡ '\x0A'))
+ pair ∷ Parser (MIMEType, [Text])
+ pair = do skipSpace
+ mime ← def
+ skipSpace1
+ exts ← sepBy1 ext $ skipWhile1 (≡ '\x20')
+ return (mime, exts)
+ <?>
+ "pair"
- emptyLine ∷ Parser (Maybe (MIMEType, [Text]))
- emptyLine = try $
- do skipWhile isSpc
- _ ← char '\x0A'
- return Nothing
+ ext ∷ Parser Text
+ ext = (decodeUtf8 <$> takeWhile1 isAlphaNum)
+ <?>
+ "ext"
-compile ∷ [ (MIMEType, [Text]) ] → Map Text MIMEType
-compile = M.fromList ∘ concat ∘ map tr
- where
- tr ∷ (MIMEType, [Text]) → [ (Text, MIMEType) ]
- tr (mime, exts) = [ (ext, mime) | ext ← exts ]
+ linebreak ∷ Parser ()
+ linebreak
+ = ( endOfLine
+ <|>
+ try (skipSpace *> char '#' *> skipManyTill anyChar endOfLine)
+ )
+ <?>
+ "linebreak"
--- |@'serializeExtMap' extMap moduleName variableName@ generates a
--- Haskell source code which contains the following things:
---
--- * A definition of module named @moduleName@.
---
--- * @variableName ∷ 'ExtMap'@ whose content is a serialization of
--- @extMap@.
---
--- The module "Network.HTTP.Lucu.MIMEType.DefaultExtensionMap" is
--- surely generated using this function.
-serializeExtMap ∷ ExtMap → String → String → String
-serializeExtMap extMap moduleName variableName
- = let hsModule = HsModule (⊥) modName (Just exports) imports decls
- modName = Module moduleName
- exports = [HsEVar (UnQual (HsIdent variableName))]
- imports = [ HsImportDecl (⊥) (Module "Network.HTTP.Lucu.MIMEType") False Nothing Nothing
- , HsImportDecl (⊥) (Module "Network.HTTP.Lucu.MIMEType.Guess") False Nothing Nothing
- , HsImportDecl (⊥) (Module "Data.Ascii") True (Just (Module "A")) Nothing
- , HsImportDecl (⊥) (Module "Data.Map") True (Just (Module "M")) Nothing
- , HsImportDecl (⊥) (Module "Data.Text") True (Just (Module "T")) Nothing
- ]
- decls = [ HsTypeSig (⊥) [HsIdent variableName]
- (HsQualType []
- (HsTyCon (UnQual (HsIdent "ExtMap"))))
- , HsFunBind [HsMatch (⊥) (HsIdent variableName)
- [] (HsUnGuardedRhs extMapExp) []]
- ]
- extMapExp = HsApp (HsVar (Qual (Module "M") (HsIdent "fromList"))) (HsList records)
- comment = "{- !!! WARNING !!!\n"
- ⧺ " This file is automatically generated.\n"
- ⧺ " DO NOT EDIT BY HAND OR YOU WILL REGRET -}\n\n"
- in
- comment ⧺ prettyPrint hsModule ⧺ "\n"
+compile ∷ Ord k ⇒ [(v, [k])] → Either (k, v, v) (Map k v)
+compile = go (∅) ∘ concat ∘ (tr <$>)
where
- records ∷ [HsExp]
- records = map record $ M.assocs extMap
+ tr ∷ (v, [k]) → [(k, v)]
+ tr (v, ks) = [(k, v) | k ← ks]
- record ∷ (Text, MIMEType) → HsExp
- record (ext, mime)
- = HsTuple
- [ HsApp (HsVar (Qual (Module "T") (HsIdent "pack")))
- (HsLit (HsString (T.unpack ext)))
- , mimeToExp mime
- ]
-
- mimeToExp ∷ MIMEType → HsExp
- mimeToExp mt
- = HsApp (HsVar (UnQual (HsIdent "parseMIMEType")))
- (HsParen
- (HsApp (HsVar (Qual (Module "A") (HsIdent "unsafeFromString")))
- (HsLit (HsString $ mimeToString mt))))
+ go ∷ Ord k ⇒ Map k v → [(k, v)] → Either (k, v, v) (Map k v)
+ go m [] = Right m
+ go m ((k, v):xs)
+ = case M.insertLookupWithKey' f k v m of
+ (Nothing, m') → go m' xs
+ (Just v0, _ ) → Left (k, v0, v)
- mimeToString ∷ MIMEType → String
- mimeToString = A.toString ∘ A.fromAsciiBuilder ∘ printMIMEType
+ f ∷ k → v → v → v
+ f _ _ = id
+
+-- |Guess the MIME Type of a file.
+guessTypeByFileName ∷ ExtMap → FilePath → Maybe MIMEType
+guessTypeByFileName (ExtMap m) fpath
+ = case takeExtension fpath of
+ [] → Nothing
+ (_:ext) → M.lookup (cs ext) m
projects / Lucu.git / blobdiff