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{-# LANGUAGE DeriveDataTypeable #-}
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE TypeFamilies #-}
module Main where
import Control.Monad.Reader (ask)
import Control.Monad.State (get, put)
import Data.Acid
import Data.Acid.Advanced
import Data.Acid.Local
import Data.ByteString (ByteString)
import Data.Char (toLower)
import Data.Data (Data, Typeable)
import Data.IxSet (Indexable (..), IxSet (..), Proxy (..),
getOne, ixFun, ixSet, (@=))
import Data.List (insert)
import Data.SafeCopy
import Data.Text (Text, pack)
import Data.Text.Lazy (toStrict)
import Data.Time
import Happstack.Server (FromReqURI (..))
import System.Environment (getEnv)
import qualified Crypto.Hash.SHA512 as SHA (hash)
import qualified Data.ByteString.Base64 as B64 (encode)
import qualified Data.ByteString.Char8 as B
import qualified Data.IxSet as IxSet
import qualified Data.Text as Text
newtype EntryId = EntryId { unEntryId :: Integer }
deriving (Eq, Ord, Data, Enum, Typeable)
$(deriveSafeCopy 2 'base ''EntryId)
instance Show EntryId where
show = show . unEntryId
data BlogLang = EN | DE
deriving (Eq, Ord, Data, Typeable)
instance Show BlogLang where
show DE = "de"
show EN = "en"
instance FromReqURI BlogLang where
fromReqURI sub =
case map toLower sub of
"de" -> Just DE
"en" -> Just EN
_ -> Nothing
$(deriveSafeCopy 0 'base ''BlogLang)
data Comment = Comment {
cdate :: UTCTime,
cauthor :: Text,
ctext :: Text
} deriving (Eq, Ord, Show, Data, Typeable)
$(deriveSafeCopy 0 'base ''Comment)
data Entry_v0 = Entry_v0 {
entryId_v0 :: EntryId,
lang_v0 :: BlogLang,
author_v0 :: Text,
title_v0 :: Text,
btext_v0 :: Text,
mtext_v0 :: Text,
edate_v0 :: UTCTime,
tags :: [Text],
comments :: [Comment]
} deriving (Eq, Ord, Show, Data, Typeable)
$(deriveSafeCopy 0 'base ''Entry_v0)
data Entry = Entry {
entryId :: EntryId,
lang :: BlogLang,
author :: Text,
title :: Text,
btext :: Text,
mtext :: Text,
edate :: UTCTime
} deriving (Eq, Ord, Show, Data, Typeable)
$(deriveSafeCopy 2 'extension ''Entry)
instance Migrate Entry where
type MigrateFrom Entry = Entry_v0
migrate (Entry_v0 ei l a t b m ed _ _) =
Entry ei l a t b m ed
-- ixSet requires different datatypes for field indexes, so let's define some
newtype Author_v0 = Author_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype Author = Author Text deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''Author)
instance Migrate Author where
type MigrateFrom Author = Author_v0
migrate (Author_v0 x) = Author x
newtype Title_v0 = Title_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype Title = Title Text deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''Title)
instance Migrate Title where
type MigrateFrom Title = Title_v0
migrate (Title_v0 x) = Title x
newtype BText_v0 = BText_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype BText = BText Text deriving (Eq, Ord, Data, Typeable) -- standard text
$(deriveSafeCopy 2 'extension ''BText)
instance Migrate BText where
type MigrateFrom BText = BText_v0
migrate (BText_v0 x) = BText x
newtype MText_v0 = MText_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype MText = MText Text deriving (Eq, Ord, Data, Typeable) -- "read more" text
$(deriveSafeCopy 2 'extension ''MText)
instance Migrate MText where
type MigrateFrom MText = MText_v0
migrate (MText_v0 x) = MText x
newtype Tag_v0 = Tag_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype Tag = Tag Text deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''Tag)
instance Migrate Tag where
type MigrateFrom Tag = Tag_v0
migrate (Tag_v0 x) = Tag x
newtype EDate_v0 = EDate_v0 UTCTime deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype EDate = EDate UTCTime deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''EDate)
instance Migrate EDate where
type MigrateFrom EDate = EDate_v0
migrate (EDate_v0 x) = EDate x
newtype SDate_v0 = SDate_v0 UTCTime deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype SDate = SDate UTCTime deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''SDate)
instance Migrate SDate where
type MigrateFrom SDate = SDate_v0
migrate (SDate_v0 x) = SDate x
newtype Username_v0 = Username_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype Username = Username Text deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''Username)
instance Migrate Username where
type MigrateFrom Username = Username_v0
migrate (Username_v0 x) = Username x
newtype SessionID_v0 = SessionID_v0 Text deriving (Eq, Ord, Data, Typeable, SafeCopy)
newtype SessionID = SessionID Text deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 2 'extension ''SessionID)
instance Migrate SessionID where
type MigrateFrom SessionID = SessionID_v0
migrate (SessionID_v0 x) = SessionID x
instance Indexable Entry where
empty = ixSet [ ixFun $ \e -> [ entryId e]
, ixFun $ (:[]) . lang
, ixFun $ \e -> [ Author $ author e ]
, ixFun $ \e -> [ Title $ title e]
, ixFun $ \e -> [ BText $ btext e]
, ixFun $ \e -> [ MText $ mtext e]
, ixFun $ \e -> [ EDate $ edate e]
]
data User = User {
username :: Text,
password :: ByteString
} deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 0 'base ''User)
data Session = Session {
sessionID :: Text,
user :: User,
sdate :: UTCTime
} deriving (Eq, Ord, Data, Typeable)
$(deriveSafeCopy 0 'base ''Session)
instance Indexable User where
empty = ixSet [ ixFun $ \u -> [Username $ username u]
, ixFun $ (:[]) . password
]
instance Indexable Session where
empty = ixSet [ ixFun $ \s -> [SessionID $ sessionID s]
, ixFun $ (:[]) . user
, ixFun $ \s -> [SDate $ sdate s]
]
data Blog = Blog {
blogSessions :: IxSet Session,
blogUsers :: IxSet User,
blogEntries :: IxSet Entry
} deriving (Data, Typeable)
latestEntries :: BlogLang -> Query Blog [Entry]
latestEntries lang =
do b@Blog{..} <- ask
return $ IxSet.toDescList (Proxy :: Proxy EDate) $ blogEntries @= lang
$(deriveSafeCopy 0 'base ''Blog)
$(makeAcidic ''Blog ['latestEntries])
initialBlogState :: Blog
initialBlogState =
Blog { blogSessions = empty
, blogUsers = empty
, blogEntries = empty }
main :: IO ()
main = do
putStrLn "Opening state"
acid <- openLocalStateFrom "/var/tazblog/BlogState" initialBlogState
entries <- query acid (LatestEntries EN)
print $ length entries
print $ head entries
putStrLn "Creating checkpoint"
createCheckpoint acid
putStrLn "Closing state"
closeAcidState acid
|
