{-# LANGUAGE OverloadedStrings #-}
module Main where
-import Web.Scotty
+import Web.Scotty.Cookie
+import Web.Scotty.Trans
import qualified Data.Text.Lazy as T
-import qualified Data.Text.Lazy.IO as T
-import Control.Monad.IO.Class
+import Data.List
+import Data.Time
+import qualified Data.Map.Lazy as Map
+import Data.Maybe
+import Data.Ord
+import Data.IORef
+import Control.Exception
import Control.Monad
+import Control.Monad.IO.Class
+import Control.Monad.Trans.Class
+import qualified Control.Monad.Trans.State as S
import qualified Text.MMark as M
import qualified Text.MMark.Extension.Common as M
+import Text.Casing
+import Text.Read (readMaybe)
import Lucid
import Lucid.Base
import System.Directory
import System.FilePath
+import System.Random
+import System.IO.Error
import Network.HTTP.Types
+type Sessions = Map.Map T.Text T.Text
+type ActionM = ActionT T.Text (S.StateT Sessions IO)
+
+-- | Makes a function that carries over the state from one
+-- request to the next
+mkPreserve :: s -> IO ((S.StateT s IO) a -> IO a)
+mkPreserve initS = do
+ ref <- newIORef initS
+ return $ \f -> do
+ s <- readIORef ref
+ (x, s') <- S.runStateT f s
+ writeIORef ref s'
+ return x
+
+-- TODO: Use hashes
+logins :: Map.Map T.Text T.Text
+logins = Map.fromList
+ [ ("luke", "pass")
+ , ("dave", "abcd")
+ , ("antonia", "1234")
+ , ("owen", "haskell")
+ ]
+-- | Checks if the user is logged in
+loggedIn :: ActionM Bool
+loggedIn = do
+ mCookie <- getCookie "session"
+ case mCookie of
+ Nothing -> return False
+ Just cookie -> Map.member (T.fromStrict cookie) <$> lift S.get
+
+-- | Returns the current username
+currentUser :: ActionM (Maybe T.Text)
+currentUser = do
+ mCookie <- getCookie "session"
+ case mCookie of
+ Nothing -> return Nothing
+ Just cookie -> Map.lookup (T.fromStrict cookie) <$> lift S.get
+
main :: IO ()
-main = scotty 3000 $ do
+main = do
+ preserve <- mkPreserve mempty
+ createDirectory "posts" `catch` (\e -> unless (isAlreadyExistsError e) (throw e))
+ scottyT 3000 preserve $ do
get "/style.css" $ file "style.css"
- get "/create" $ html $ renderText $ html_ $ do
- head_ style
- body_ $ with form_ [action_ "create", method_ "post"] $ do
- input_ [name_ "title", type_ "text"]
- with textarea_ [name_ "body", placeholder_ "body"] ""
- input_ [type_ "submit"]
+ get "/create" $ do
+ authed <- loggedIn
+ if authed
+ then template "Create" $ do
+ h1_ "Create a new post"
+ form_ [action_ "create", method_ "post"] $ do
+ input_ [name_ "title", type_ "text", placeholder_ "Title"]
+ br_ []
+ textarea_ [name_ "body", placeholder_ "# Your markdown here"] ""
+ br_ []
+ input_ [type_ "submit", value_ "Post"]
+ else do
+ text "You're not logged in"
+ status unauthorized401
post "/create" $ do
- title <- param "title"
- body <- param "body"
- let fp = "posts" </> T.unpack title <.> "md"
- liftIO $ T.writeFile fp body
- redirect ("post/" <> title)
+ t <- param "title"
+ b <- param "body"
+ p <- createPost t b
+ redirect (linkToPost p)
post "/login" $ do
username <- param "username"
password <- param "password"
- if username /= ("luke" :: T.Text) || password /= ("pass" :: T.Text)
- then status unauthorized401
- else redirect "/create"
+ if Map.lookup username logins /= Just password
+ then do
+ text "Invalid username and/or password"
+ status unauthorized401
+ else do
+ session <- T.pack . show <$> liftIO (randomIO :: IO Int)
+ lift $ S.modify (Map.insert session username)
+ setSimpleCookie "session" (T.toStrict session)
+ redirect "/"
+
+ post "/logout" $ deleteCookie "session" >> redirect "/"
get "/" $ do
- posts <- fmap dropExtension <$> liftIO (listDirectory "posts")
- contents <- mapM render posts
+ posts <- take 5 <$> liftIO loadAll
+ template "Cool blog" $ sequence (mapMaybe render posts)
+
+ get "/posts/:post" $ do
+ name <- param "post"
+ mPost <- liftIO (load name)
+ case mPost of
+ Nothing -> status notFound404
+ Just p -> case render p of
+ Nothing -> status internalServerError500
+ Just content -> template (postTitle p) content
+
+ get "/author/:author" $ do
+ author <- param "author"
+ posts <- filter ((== author) . postAuthor) <$> liftIO loadAll
+ let title = "Posts by " <> author
+ template title $ do
+ h1_ (toHtml title)
+ sequence (mapMaybe render posts)
+
+template :: T.Text -> Html a -> ActionM ()
+template title content = do
+ authed <- loggedIn
html $ renderText $ html_ $ do
- head_ style
+ head_ $ style >> title_ (toHtml title)
body_ $ do
- with form_ [action_ "/login", method_ "post"] $ do
- input_ [name_ "username", placeholder_ "username", type_ "text"]
- input_ [name_ "password", placeholder_ "password", type_ "password"]
- input_ [type_ "submit"]
- sequence contents
+ term "nav" $ do
+ a_ [href_ "/"] "🏠 Cool Blog"
+ if authed
+ then do
+ " " >> a_ [href_ "/create"] "Create a Post"
+ form_ [action_ "/logout", method_ "post", class_ "login-form"] $
+ input_ [type_ "submit", value_ "Log Out"]
+ else form_ [action_ "/login", method_ "post", class_ "login-form"] $ do
+ input_ [name_ "username", placeholder_ "Username", type_ "text"]
+ input_ [name_ "password", placeholder_ "Password", type_ "password"]
+ input_ [type_ "submit", value_ "Log In"]
+ content
+ where style = link_ [Attribute "rel" "stylesheet", Attribute "href" "/style.css"]
+data Post = Post
+ { postBody :: T.Text
+ , postTitle :: T.Text
+ , postDate :: UTCTime
+ , postAuthor :: T.Text
+ } deriving (Read, Show)
- get "/post/:post" $ do
- post <- param "post"
- content <- render post
- html $ renderText $ html_ $ do
- head_ style
- body_ content
-
- where
- style = link_ [Attribute "rel" "stylesheet", Attribute "href" "style.css"]
-
-render :: String -> ActionM (Html ())
-render post = do
- let name = "posts" </> post <.> ".md"
- markdown <- T.toStrict <$> liftIO (T.readFile name)
- case M.parse name markdown of
- Left e -> return "shit"
- Right doc -> return $ M.render (M.useExtensions extensions doc)
+loadAll :: IO [Post]
+loadAll = do
+ fps <- listDirectory "posts"
+ posts <- catMaybes <$> mapM load fps
+ return $ sortOn (Down . postDate) posts
+
+load :: String -> IO (Maybe Post)
+load name = do
+ let fp = "posts" </> name
+ guard =<< doesFileExist fp
+ readMaybe <$> readFile fp
+
+render :: Post -> Maybe (Html ())
+render p@(Post markdown title date author) =
+ case M.parse (pathToPost p) (T.toStrict markdown) of
+ Left _ -> Nothing
+ Right doc -> Just $
+ article_ [id_ (T.toStrict title)] $ do
+ header_ $ do
+ a_ [href_ (T.toStrict $ linkToPost p)] $
+ h1_ $ toHtml title
+ a_ [href_ (T.toStrict $ "/author/" <> postAuthor p)] $
+ address_ ("By " >> toHtml author)
+ time_ [datetime_ (T.toStrict $ T.pack (show date))] $ toHtml dateStr
+ M.render (M.useExtensions extensions doc)
where extensions = [M.ghcSyntaxHighlighter, M.skylighting, M.footnotes]
+ dateStr = T.pack $ formatTime defaultTimeLocale "%a %e %B %Y" date
+
+linkToPost :: Post -> T.Text
+linkToPost p = T.pack $ "/posts" </> kebab (T.unpack (postTitle p))
+
+pathToPost :: Post -> FilePath
+pathToPost p = "posts" </> kebab (T.unpack (postTitle p))
+
+-- | Creates and saves a new post
+createPost :: T.Text
+ -- ^ The title of the post
+ -> T.Text
+ -- ^ The markdown body
+ -> ActionM Post
+ -- ^ The freshly created post
+createPost title markdown = do
+ auth <- do
+ ma <- currentUser
+ case ma of
+ Just a -> return a
+ Nothing -> raise "Not logged in"
+ curTime <- liftIO getCurrentTime
+ let p = Post markdown title curTime auth
+ liftIO $ writeFile (pathToPost p) (show p)
+ return p
projects / blog.git / blobdiff