diff options
Diffstat (limited to 'src/Hakyll/Core/Resource/Provider.hs')
| -rw-r--r-- | src/Hakyll/Core/Resource/Provider.hs | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/src/Hakyll/Core/Resource/Provider.hs b/src/Hakyll/Core/Resource/Provider.hs index ebd5984..2ed7797 100644 --- a/src/Hakyll/Core/Resource/Provider.hs +++ b/src/Hakyll/Core/Resource/Provider.hs @@ -1,3 +1,4 @@ +-------------------------------------------------------------------------------- -- | This module provides an API for resource providers. Resource providers -- allow Hakyll to get content from resources; the type of resource depends on -- the concrete instance. @@ -19,22 +20,30 @@ module Hakyll.Core.Resource.Provider , resourceModified ) where + +-------------------------------------------------------------------------------- import Control.Applicative ((<$>)) import Control.Concurrent (MVar, readMVar, modifyMVar_, newMVar) import Data.Map (Map) import qualified Data.Map as M import qualified Data.Set as S + +-------------------------------------------------------------------------------- import Data.Time (UTCTime) import qualified Crypto.Hash.MD5 as MD5 import qualified Data.ByteString as B import qualified Data.ByteString.Lazy as LB -import Hakyll.Core.Store + +-------------------------------------------------------------------------------- +import Hakyll.Core.Store (Store) import Hakyll.Core.Resource +import qualified Hakyll.Core.Store as Store + +-------------------------------------------------------------------------------- -- | A value responsible for retrieving and listing resources --- data ResourceProvider = ResourceProvider { -- | A set of all resources this provider is able to provide resourceSet :: S.Set Resource @@ -48,8 +57,9 @@ data ResourceProvider = ResourceProvider resourceModifiedCache :: MVar (Map Resource Bool) } + +-------------------------------------------------------------------------------- -- | Create a resource provider --- makeResourceProvider :: [Resource] -- ^ Resource list -> (Resource -> IO String) -- ^ String reader -> (Resource -> IO LB.ByteString) -- ^ ByteString reader @@ -58,22 +68,27 @@ makeResourceProvider :: [Resource] -- ^ Resource list makeResourceProvider l s b t = ResourceProvider (S.fromList l) s b t <$> newMVar M.empty + +-------------------------------------------------------------------------------- -- | Get the list of all resources resourceList :: ResourceProvider -> [Resource] resourceList = S.toList . resourceSet + +-------------------------------------------------------------------------------- -- | Check if a given identifier has a resource --- resourceExists :: ResourceProvider -> Resource -> Bool resourceExists provider = flip S.member $ resourceSet provider + +-------------------------------------------------------------------------------- -- | Retrieve a digest for a given resource --- resourceDigest :: ResourceProvider -> Resource -> IO B.ByteString resourceDigest provider = fmap MD5.hashlazy . resourceLBS provider + +-------------------------------------------------------------------------------- -- | Check if a resource was modified --- resourceModified :: ResourceProvider -> Store -> Resource -> IO Bool resourceModified provider store r = do cache <- readMVar mvar @@ -90,21 +105,21 @@ resourceModified provider store r = do where mvar = resourceModifiedCache provider + +-------------------------------------------------------------------------------- -- | Check if a resource digest was modified --- digestModified :: ResourceProvider -> Store -> Resource -> IO Bool digestModified provider store r = do -- Get the latest seen digest from the store - lastDigest <- storeGet store itemName identifier + lastDigest <- Store.get store key -- Calculate the digest for the resource newDigest <- resourceDigest provider r -- Check digests - if Found newDigest == lastDigest + if Store.Found newDigest == lastDigest -- All is fine, not modified then return False -- Resource modified; store new digest - else do storeSet store itemName identifier newDigest + else do Store.set store key newDigest return True where - identifier = toIdentifier r - itemName = "Hakyll.Core.ResourceProvider.digestModified" + key = ["Hakyll.Core.ResourceProvider.digestModified", unResource r] |