1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116
|
--------------------------------------------------------------------------------
{-# LANGUAGE CPP #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE Rank2Types #-}
module Hakyll.Core.Rules.Internal
( RulesRead (..)
, RuleSet (..)
, RulesState (..)
, emptyRulesState
, Rules (..)
, runRules
) where
--------------------------------------------------------------------------------
#if !MIN_VERSION_base(4,13,0)
import Control.Monad.Fail (MonadFail)
#endif
import Control.Monad.Reader (ask)
import Control.Monad.RWS (RWST, runRWST)
import Control.Monad.Trans (liftIO)
import qualified Data.Map as M
import Data.Set (Set)
--------------------------------------------------------------------------------
import Hakyll.Core.Compiler.Internal
import Hakyll.Core.Identifier
import Hakyll.Core.Identifier.Pattern
import Hakyll.Core.Item.SomeItem
import Hakyll.Core.Metadata
import Hakyll.Core.Provider
import Hakyll.Core.Routes
--------------------------------------------------------------------------------
data RulesRead = RulesRead
{ rulesProvider :: Provider
, rulesMatches :: [Identifier]
, rulesVersion :: Maybe String
}
--------------------------------------------------------------------------------
data RuleSet = RuleSet
{ -- | Accumulated routes
rulesRoutes :: Routes
, -- | Accumulated compilers
rulesCompilers :: [(Identifier, Compiler SomeItem)]
, -- | A set of the actually used files
rulesResources :: Set Identifier
, -- | A pattern we can use to check if a file *would* be used. This is
-- needed for the preview server.
rulesPattern :: Pattern
}
--------------------------------------------------------------------------------
instance Semigroup RuleSet where
(<>) (RuleSet r1 c1 s1 p1) (RuleSet r2 c2 s2 p2) =
RuleSet (mappend r1 r2) (mappend c1 c2) (mappend s1 s2) (p1 .||. p2)
instance Monoid RuleSet where
mempty = RuleSet mempty mempty mempty mempty
mappend = (<>)
--------------------------------------------------------------------------------
data RulesState = RulesState
{ rulesRoute :: Maybe Routes
, rulesCompiler :: Maybe (Compiler SomeItem)
}
--------------------------------------------------------------------------------
emptyRulesState :: RulesState
emptyRulesState = RulesState Nothing Nothing
--------------------------------------------------------------------------------
-- | The monad used to compose rules
newtype Rules a = Rules
{ unRules :: RWST RulesRead RuleSet RulesState IO a
} deriving (Monad, MonadFail, Functor, Applicative)
--------------------------------------------------------------------------------
instance MonadMetadata Rules where
getMetadata identifier = Rules $ do
provider <- rulesProvider <$> ask
liftIO $ resourceMetadata provider identifier
getMatches pattern = Rules $ do
provider <- rulesProvider <$> ask
return $ filterMatches pattern $ resourceList provider
--------------------------------------------------------------------------------
-- | Run a Rules monad, resulting in a 'RuleSet'
runRules :: Rules a -> Provider -> IO RuleSet
runRules rules provider = do
(_, _, ruleSet) <- runRWST (unRules rules) env emptyRulesState
-- Ensure compiler uniqueness
let ruleSet' = ruleSet
{ rulesCompilers = M.toList $
M.fromListWith (flip const) (rulesCompilers ruleSet)
}
return ruleSet'
where
env = RulesRead
{ rulesProvider = provider
, rulesMatches = []
, rulesVersion = Nothing
}
|