use a ReaderT to pass environment around

.gitignore

@@ -1,16 +1,3 @@
 dist
-cabal-dev
-*.o
-*.hi
-*.chi
-*.chs.h
-*.dyn_o
-*.dyn_hi
-.virtualenv
-.hpc
-.hsenv
-.cabal-sandbox/
-cabal.sandbox.config
-*.prof
-*.aux
-*.hp
+result
+default.nix

LICENSE

@@ -1,3 +1,674 @@
-Dual licensed under the MIT and GPL licenses:
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-http://www.gnu.org/licenses/gpl.html
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+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+              END OF TERMS AND CONDITIONS
+
+     How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.

README.md

@@ -27,13 +27,15 @@ The app will start serving on `https://localhost:3000`, listening on every activ
 
 You can change the options by editing the config file.
 When you start the app an empty one will be created in:
-`$XDG_CONFIG_HOME/breve` or `~/.config/breve` if unset.
+`$XDG_CONFIG_HOME/breve`, `~/.config/breve` if unset,
+or you can pass a path as the first argument of breve.
 
 The default values are:
 
 ```ini
 hostname = "localhost"
 port     = 3000
+baseurl  = "https://localhost:3000/"
 urltable = "$XDG_CONFIG_HOME/breve"
 tls {
   cert  = "/usr/share/tls/breve.crt"
@@ -48,6 +50,10 @@ tls {
 
 ## License
 
-Dual licensed under the MIT and GPL licenses:  
-http://www.opensource.org/licenses/mit-license.php  
-http://www.gnu.org/licenses/gpl.html
+Copyright (C) 2019 Michele Guerini Rocco
+
+This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.

Setup.hs

@@ -1,2 +0,0 @@
-import Distribution.Simple
-main = defaultMain

breve.cabal

@@ -1,39 +1,43 @@
 name:                breve
-version:             0.4.3.1
+version:             0.5.0.0
 synopsis:            a url shortener
 description:
 
   Breve is a web application that provides a simple interface to
   shortening long urls creating links smaller and easier to remember.
 
-homepage:            https://github.com/rnhmjoj/breve
-license:             MIT
+homepage:            https://maxwell.ydns.eu/git/rnhmjoj/breve
+license:             GPL-3
 license-file:        LICENSE
 author:              rnhmjoj
-maintainer:          micheleguerinirocco@me.com
-copyright:           (C) Michele Guerini Rocco 2015
+maintainer:          rnhmjoj@inventati.org
+copyright:           (C) Michele Guerini Rocco 2019
 category:            Web
 build-type:          Simple
 extra-source-files:  README.md, LICENSE
-data-files:          static/*.png, static/*.css
+data-files:          static/*.png, static/*.css static/*.woff
 cabal-version:       >=1.10
 
 source-repository head
   type: git
-  location: https://github.com/rnhmjoj/breve
+  location: https://maxwell.ydns.eu/git/rnhmjoj/breve
 
 executable breve
   main-is:            Main.hs
   hs-source-dirs:     src
   default-language:   Haskell2010
   other-modules:      Application, Views, Breve.Settings,
-                     Breve.Generator, Breve.UrlTable
-  other-extensions:  OverloadedStrings
-  build-depends:     base >=4.8 && <5.0, warp, warp-tls, tls,
-                     Spock, Spock-core, blaze-html, http-types,
-                     wai, wai-middleware-static, wai-extra,
-                     transformers, mtl,
-                     text, aeson, bytestring, binary,
+                      Breve.Generator, Breve.UrlTable,
+                      Paths_breve
+  default-extensions: OverloadedStrings
+  other-extensions:   RecordWildCards, DeriveGeneric,
+                      DataKinds, KindSignatures, TypeOperators
+  build-depends:      base >=4.8 && <5.0,
+                      warp, warp-tls, tls, blaze-html,
+                      servant-server, servant-rawm, servant-blaze,
+                      wai, wai-extra, streaming-commons, http-api-data,
+
+                      mtl, text, aeson, bytestring, binary,
                       hashtables, cryptohash, random,
-                     xdg-basedir, configurator, directory
-  ghc-options:       -threaded -O2
+                      configurator, directory
+  ghc-options:        -threaded -O2 "-with-rtsopts=-N -qg"

src/Application.hs

@@ -1,79 +1,205 @@
-{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE DataKinds            #-}
+{-# LANGUAGE KindSignatures       #-}
+{-# LANGUAGE TypeOperators        #-}
+{-# LANGUAGE DeriveGeneric        #-}
+
+{-|
+This module contains the web application
+and API implementation of Breve.
+-}
 module Application where
 
+-- Breve modules
 import Breve.Generator
 import Breve.UrlTable
-import Paths_breve             (getDataFileName)
 import Views
 
-import Data.Monoid
+-- Misc
 import Control.Monad.IO.Class   (liftIO)
-import Data.Aeson hiding       (json)
-import Data.Text               (Text)
+import Control.Monad.Reader     (ReaderT, runReaderT, asks)
 import qualified Data.Text.IO   as T
 
-import Web.Spock.Core
-import Network.HTTP.Types.Status
-import Network.Wai (Middleware)
-import Network.Wai.Middleware.Static
-import Network.Wai.Middleware.RequestLogger
+-- JSON conversion
+import Data.Text                (Text)
+import Data.Aeson               (ToJSON)
+import GHC.Generics             (Generic)
+
+-- HTML replies
+import Text.Blaze.Html5              (Html)
+import Text.Blaze.Html.Renderer.Utf8 (renderHtml)
+
+-- API definition
+import Servant
+import Servant.HTML.Blaze       (HTML)
+import Servant.RawM             as R
+import Web.FormUrlEncoded       (FromForm(..), parseUnique)
 
 
-serveStatic :: FilePath -> Middleware
-serveStatic = staticPolicy . addBase
+-- * Types
+
+-- | Custom handler type with a
+-- reader environment
+type AppM = ReaderT AppEnv Handler
+
+-- | The environment associated
+-- to 'AppM'
+data AppEnv = AppEnv
+  { bindUrl   :: Text
+  , urlTable  :: UrlTable
+  , staticDir :: FilePath
+  }
+
+-- | API successful reply
+--
+-- This is the reply returned by the JSON API
+-- handler when the url has been shortned
+-- successfully.
+data ApiReply = ApiReply
+  { link     :: Url  -- ^ shortened url
+  , name     :: Name -- ^ just the name
+  , original :: Url  -- ^ original url
+  } deriving Generic
+
+instance ToJSON ApiReply
+
+-- | This type is just a wrapper around a 'Text'
+-- value. It's used to create a 'FromForm' instance
+-- for a 'Url'.
+newtype UrlForm = UrlForm Text
+
+instance FromForm UrlForm where
+  fromForm f = UrlForm <$> parseUnique "url" f
 
 
-reply :: Status -> Text -> ActionT IO ()
-reply code text = setStatus code >> render (message text)
+-- * Breve API
 
+-- | API spec
+--
+-- Breve has two main components:
+--
+-- 1. the web app
+-- 2. the JSON API itself
+type Breve = API :<|> App
 
-logStr :: Text -> ActionT IO ()
-logStr = liftIO . T.putStrLn
+-- | Web app spec
+--
+-- +----------+------+----------------------+
+-- | path     | type | description          |
+-- +==========+======+======================+
+-- | /        | GET  | homepage             |
+-- +----------+------+----------------------+
+-- | /        | POST | upload a new url     |
+-- +----------+------+----------------------+
+-- | /static  | GET  | static assets        |
+-- +----------+------+----------------------+
+-- | /:name   | GET  | resolves a short url |
+-- +----------+------+----------------------+
+type App =
+       Get '[HTML] Html
+  :<|> "static" :> RawM
+  :<|> Capture "name" Name :> Redirect
+  :<|> ReqBody '[FormUrlEncoded] UrlForm :> Post '[HTML] Html
 
+-- | JSON API spec
+--
+-- +----------+------+----------------------+
+-- | path     | type | description          |
+-- +==========+======+======================+
+-- | /api     | POST | upload a new url     |
+-- +----------+------+----------------------+
+type API =
+  "api" :> ReqBody '[FormUrlEncoded] UrlForm :> Post '[JSON] ApiReply
 
-app :: Url -> UrlTable -> SpockT IO ()
-app url' table = do
-  static <- liftIO (getDataFileName "static/")
+-- | Breve application
+--
+-- Notes:
+--
+-- * @api@ is an empty value that brings the type
+-- 'Breve' to the 'serve' function. If Haskell were
+-- depedently typed it would just be @serve Breve@
+--
+-- * hoistServer flattens the AppM monad stack
+-- in the breveServer definition
+breve :: AppEnv -> Application
+breve env = serve api (hoistServer api nt breveServer)
+  where api = Proxy :: Proxy Breve
+        nt x = runReaderT x env
 
-  middleware (serveStatic static)
-  middleware logStdout
+-- | Empty application
+--
+-- This app does *nothing* but it's useful nonetheless:
+-- it will be used as a basis to run the 'forceSSL'
+-- middleware.
+emptyApp :: Application
+emptyApp = serve (Proxy :: Proxy EmptyAPI) emptyServer
 
-  get "/" $ render index
+-- * Handlers
 
-  get var $ \name -> do
+-- | Breve server
+--
+-- This is just an ordered collection of handlers
+-- following the 'Breve' API spec.
+--
+-- Note: 'RawM' is  required because Servant doesn't
+-- allow the creation of a raw 'Application' from a
+-- monadic value.
+breveServer :: ServerT Breve AppM
+breveServer = api :<|> app
+  where app =  homepage
+          :<|> (R.serveDirectoryWebApp =<< asks staticDir)
+          :<|> resolver
+          :<|> uploader
+
+-- | Serves the homepage
+homepage :: AppM Html
+homepage = pure index
+
+-- | Resolves a 'Name' to the full 'Url'
+resolver :: Name -> AppM Redirection
+resolver name = do
+  table <- asks urlTable
   url   <- liftIO (extract table name)
   case url of
-      Nothing  -> reply status404 "404: does not exist"
+    Nothing  ->
+      throwError $ err404 { errBody = renderHtml (message "404: not found") }
     Just url -> do
       logStr ("Resolved " <> name <> " -> " <> url)
-        redirect url
+      pure (addHeader url NoContent)
 
-  post "/" $ do
-    url <- param "url"
-    case url of
-      Nothing  -> reply status400 "400: bad request"
-      Just url -> do
+
+-- | Takes a 'UrlForm' via POST
+-- and prints the shortned one
+uploader :: UrlForm -> AppM Html
+uploader (UrlForm url) = do
+  table <- asks urlTable
+  bind  <- asks bindUrl
   name  <- liftIO (insert table url)
   logStr ("Registered " <> url <> " -> " <> name)
-        render (done $ url' <> name)
+  pure (done $ bind <> name)
 
-  post "api" $ do
-    url <- param "url"
-    case url of
-      Nothing  -> do
-        setStatus status400
-        json $ object [ "error" .= ("bad request"       :: Text )
-                      , "msg"   .= ("missing url field" :: Text ) ]
-      Just url -> do
+-- | Takes a 'Url' via POST and returns
+-- the shortned one in an 'ApiReply' as JSON.
+api :: UrlForm -> AppM ApiReply
+api (UrlForm url) = do
+  table <- asks urlTable
+  bind  <- asks bindUrl
   name  <- liftIO (insert table url)
   logStr ("Registered " <> url <> " -> " <> name)
-        json $ object [ "link"     .= (url' <> name)
-                      , "name"     .= name
-                      , "original" .= url ]
+  pure $ ApiReply { link     = (bind <> name)
+                  , name     = name
+                  , original = url
+                  }
 
+-- * Misc
 
-toTLS :: Text -> SpockT IO ()
-toTLS host = do
-  get var (redirect . new)
-  get "/" (redirect $ new "")
-  where new url = "https://" <> host <> "/" <> url
+-- | Handy function to log to stdout
+logStr :: Text -> AppM ()
+logStr = liftIO . T.putStrLn . ("[breve] " <>)
+
+-- | Verb that encodes an HTTP 302 redirection
+type Redirect =
+  Verb 'GET 302 '[PlainText] Redirection
+
+-- | Reply with Location redirect header
+type Redirection =
+  Headers '[Header "Location" Text] NoContent

src/Breve/Generator.hs

@@ -1,8 +1,12 @@
+{-|
+This module implements the algorithm
+by which a URL is converted into a word.
+-}
 module Breve.Generator
-( nameHash
-, intHash
-, Name
+( Name
 , Url
+, nameHash
+, intHash
 ) where
 
 import Control.Monad.State
@@ -13,25 +17,32 @@ import Data.ByteString.Lazy   (fromStrict)
 import Data.Text              (Text, pack)
 import Data.Text.Encoding     (encodeUtf8)
 
+-- | A phonetic word associated to a URL
 type Name = Text
+
+-- | Any kind of URL
 type Url  = Text
 
--- Choose a random element of a list
+-- | Takes a random element of a list
 choice :: [a] -> State StdGen a
 choice xs = (xs !!) <$> randomSt (0, length xs - 1)
   where randomSt = state . randomR
 
--- Generate a random phonetic string
+-- | Generates a random phonetic string
 word :: State StdGen Name
 word = pack <$> replicateM 10 letter where
   vowels     = "aeiou"
   consonants = "bcdfghjklmnpqrstvwxyz"
   letter     = choice [vowels, consonants] >>= choice
 
--- SHA256 hash to seed a generator
+-- | SHA256 hash to seed a generator
 intHash :: Url -> Int
 intHash = decode . fromStrict . hash . encodeUtf8
 
--- Assign a unique name to the url
+-- | Assigns a unique name to the given URL
+--
+-- The result is a computation based on a RNG
+-- seeded by URL itself and is therefore
+-- deterministic.
 nameHash :: Url -> Name
 nameHash = evalState word . mkStdGen . intHash

src/Breve/Settings.hs

@@ -1,11 +1,18 @@
-{-# LANGUAGE OverloadedStrings #-}
+{-|
+This module defines the Breve configuration
+parser and application settings.
+-}
+module Breve.Settings
+( AppSettings(..)
+, createEmptyIfMissing
+, settings
+) where
 
-module Breve.Settings where
+import Paths_breve (getDataFileName)
 
 import Control.Monad                  (when)
 import System.Environment             (lookupEnv)
-import System.Environment.XDG.BaseDir
-import System.Directory                (doesFileExist)
+import System.Directory               (doesFileExist, getXdgDirectory, XdgDirectory(..))
 import Data.Text                      (Text, pack)
 import Data.Configurator
 import Data.Monoid
@@ -14,49 +21,56 @@ import Network.Wai.Handler.WarpTLS     (TLSSettings (..), tlsSettingsChain)
 import Network.TLS                    (Version (..))
 import Network.TLS.Extra              (ciphersuite_strong)
 
+-- | Breve settings
 data AppSettings = AppSettings
-  { bindHost    :: Text
-  , bindPort    :: Int
-  , bindUrl     :: Text
-  , urlTable    :: FilePath
-  , tlsSettings :: TLSSettings
+  { bindHost    :: Text         -- ^ the host to bind to
+  , bindPort    :: Int          -- ^ the port to bind to
+  , bindUrl     :: Text         -- ^ the url used to reach breve
+  , urlTable    :: FilePath     -- ^ path where to save the url table
+  , staticDir   :: FilePath     -- ^ path of the static assets
+  , tlsSettings :: TLSSettings  -- ^ warp TLS settings
   }
 
-
+-- | Initialises a file if it doesn't exist
 createEmptyIfMissing :: FilePath -> IO ()
 createEmptyIfMissing file = do
   exists <- doesFileExist file
   when (not exists) (writeFile file "")
 
+-- | Configuration file parser
+settings :: Maybe FilePath -> IO AppSettings
+settings path = do
+  configPath <- case path of
+    Just path -> return path
+    Nothing   -> getXdgDirectory XdgConfig "breve"
 
-settings :: IO AppSettings
-settings = do
-  urlsPath   <- getUserDataFile   "breve" ""
-  configPath <- getUserConfigFile "breve" ""
+  urlsPath  <- getXdgDirectory XdgData "breve"
 
   config  <- load [Required configPath]
   host    <- lookupDefault "localhost"                config "hostname"
-  port   <- lookupDefault 3000                       config "port"    
+  portnum <- lookupDefault 3000                       config "port"
   urls    <- lookupDefault urlsPath                   config "urltable"
   cert    <- lookupDefault "/usr/share/tls/breve.crt" config "tls.cert"
   key     <- lookupDefault "/usr/share/tls/breve.key" config "tls.key"
   chain   <- lookupDefault []                         config "tls.chain"
 
-  createEmptyIfMissing urls
+  let
+    port = if portnum == 443 then "" else ":" <> pack (show portnum)
+    url  = "https://" <> host <> port <> "/"
 
-  let base = "https://" <> host
-      url  = if port == 443
-               then base
-               else base <> ":" <> pack (show port)
-      tls = (tlsSettingsChain cert chain key)
-        { tlsAllowedVersions = [TLS12, TLS11]
-        , tlsCiphers = ciphersuite_strong
-        }
+  baseURL <- lookupDefault url config "baseurl"
+  static <- getDataFileName "static/"
+
+  createEmptyIfMissing urls
 
   return AppSettings
     { bindHost  = host
-    , bindPort = port
-    , bindUrl  = url <> "/"
+    , bindPort  = portnum
+    , bindUrl   = baseURL
     , urlTable  = urls
-    , tlsSettings = tls
+    , staticDir = static
+    , tlsSettings = (tlsSettingsChain cert chain key)
+      { tlsAllowedVersions = [TLS12, TLS11]
+      , tlsCiphers = ciphersuite_strong
+      }
     }

src/Breve/UrlTable.hs

@@ -1,6 +1,11 @@
+{-|
+This modules defines the data structure used
+to store the URLs in memory and on disk.
+-}
 module Breve.UrlTable
 ( UrlTable
 , load
+, save
 , insert
 , extract
 ) where
@@ -12,16 +17,29 @@ import Control.Concurrent  (forkIO, threadDelay)
 import Text.Read           (readMaybe)
 import qualified Data.HashTable.IO as H
 
+-- | The hash table that stores URLs
 type UrlTable = H.CuckooHashTable Name Url
 
--- Periodically write a url table to a file
+-- | Periodically save a 'UrlTable' to a file
 sync :: UrlTable -> FilePath -> IO ()
 sync table file = forever $ do
   threadDelay (round 3.0e8)
+  save table file
+
+-- | Writes a 'UrlTable' to a file
+--
+-- The table is stored in a text file
+-- as Haskell code for semplicity.
+save :: UrlTable -> FilePath -> IO ()
+save table file = do
   content <- show <$> H.toList table
   writeFile file content
+  putStrLn "\n[breve] url table synced."
 
--- Load a url table from a file
+-- | Loads a URL table from a file
+--
+-- Once the file is loaded it will be synced
+-- periodically (every 5min) on the disk.
 load :: FilePath -> IO UrlTable
 load file = do
   content <- readFile file
@@ -31,11 +49,11 @@ load file = do
   forkIO (sync table file)
   return table
 
--- Insert the url in a table and return the name
+-- | Insert the URL in a table and return the name
 insert :: UrlTable -> Url -> IO Name
 insert table url = H.insert table new url >> return new
   where new = nameHash url
 
--- Lookup a table for the associated url
+-- | Lookup a table for the associated URL
 extract :: UrlTable -> Name -> IO (Maybe Url)
 extract = H.lookup

src/Main.hs

@@ -1,37 +1,75 @@
-{-# LANGUAGE OverloadedStrings, RecordWildCards #-}
+{-# LANGUAGE RecordWildCards #-}
 
-import Application
-import Breve.Settings
+{-|
+This is the main module, which actually
+run the Breve webserver.
+-}
+module Main where
+
+-- Breve modules
+import Application     (AppEnv(..), breve, emptyApp)
+import Breve.Settings  (AppSettings(..), settings)
 import Breve.UrlTable
 
-import Data.Text          (Text, unpack)
+-- Data conversions
+import Data.String     (IsString(..))
+import Data.Maybe      (listToMaybe)
+import Data.Text       (unpack)
+
+-- IO
+import Data.Text.IO        as T
+import Control.Exception   as E
+import Control.Monad       (when, void)
 import Control.Concurrent  (forkIO)
-import Control.Monad
+import System.Environment  (getArgs)
 
-import Web.Spock.Core
-import Network.Wai.Handler.WarpTLS (runTLS, TLSSettings)
-import Network.Wai.Handler.Warp    (run, defaultSettings, setPort)
+-- Web server
+import Servant                      (Application)
+import Network.Wai.Handler.Warp     (run, defaultSettings, setPort, setHost)
+import Network.Wai.Handler.WarpTLS  (runTLS)
 
-runBreve :: TLSSettings -> Int -> SpockT IO () -> IO ()
-runBreve tlsSettings port spock =
-  spockAsApp (spockT id spock) >>= runTLS tlsSettings settings
-  where settings = setPort port defaultSettings
+-- Middlewares
+import Network.Wai.Middleware.RequestLogger (logStdout)
+import Network.Wai.Middleware.ForceSSL      (forceSSL)
 
 
-runTLSRedirect :: Text -> IO ()
-runTLSRedirect = spockAsApp . spockT id . toTLS >=> run 80
-
-
-forkIO' :: IO () -> IO ()
-forkIO' = fmap (const ()) . forkIO
+-- * Helpers
 
+-- | Runs Breve on the Warp webserver
+runApp :: AppSettings -> Application -> IO ()
+runApp (AppSettings{..}) =
+  runTLS tlsSettings warpSettings
+  where
+    host = unpack bindHost
+    warpSettings = setPort bindPort $
+                   setHost (fromString host) defaultSettings
 
+-- | Main
+--
+-- Reads the configuration (given as the unique cli argument),
+-- sets things accordingly and runs the webserver.
 main :: IO ()
 main = do
-  AppSettings {..} <- settings
+  configPath               <- fmap listToMaybe getArgs
+  config@(AppSettings{..}) <- settings configPath
   table                    <- load urlTable
 
-  when (bindPort == 443) (forkIO' $ runTLSRedirect bindHost)
+  -- Redirect from HTTP to HTTPS when listening
+  -- on the standard port
+  when (bindPort == 443) $ void $
+    forkIO (run 80 $ forceSSL emptyApp)
 
-  putStrLn ("Serving on " ++ unpack bindUrl)
-  runBreve tlsSettings bindPort (app bindUrl table)
+  -- Save the table just before exiting
+  let exit E.UserInterrupt = save table urlTable
+      exit e               = throwIO e
+
+  -- Middlewares are functions (Application -> Application).
+  -- We use one here to add requests
+  let middlewares = logStdout
+
+  -- The environment needed while running
+  let env = AppEnv bindUrl table staticDir
+
+  handle exit $ do
+    T.putStrLn ("Serving on " <> bindUrl)
+    runApp config (middlewares $ breve env)

src/Views.hs

@@ -1,22 +1,15 @@
-{-# LANGUAGE OverloadedStrings #-}
-
+{-|
+This module contains the HTML pages used by the
+web application. These are all obtained by filling
+a single template with the page structure.
+-}
 module Views where
 
 import Data.Text                   (Text)
-import Data.Text.Lazy                (toStrict)
-import Text.Blaze.Html.Renderer.Text (renderHtml)
 import Text.Blaze.Html5            as H
 import Text.Blaze.Html5.Attributes as A
-import qualified Web.Spock.Core      as S
-
-render :: Html -> S.ActionT IO ()
-render = S.html . toStrict . renderHtml
-
-done :: Text -> Html
-done url = template $ do
-  "here's your new link: "
-  a ! href (toValue url) $ (toHtml url)
 
+-- | The homepage
 index :: Html
 index = template $ do
   H.form ! method "POST" $ do
@@ -24,9 +17,22 @@ index = template $ do
     input ! type_ "text" ! name "url"
     input ! type_ "submit" ! value "go"
 
+-- | The page shown when a new url has been
+-- submitted successfully. Takes the resulting
+-- url as an argument.
+done :: Text -> Html
+done url = template $ do
+  "here's your new link: "
+  a ! href (toValue url) $ (toHtml url)
+
+-- | Displays a text message in the page center
 message :: Text -> Html
 message = template . toHtml
 
+-- | The main Breve template
+--
+-- Takes HTML code and embeds it in the
+-- inner page container.
 template :: Html -> Html
 template fill =
   docTypeHtml $ do
@@ -36,17 +42,16 @@ template fill =
       meta ! name "keywords" ! content "url, shortener"
       meta ! name "author" ! content "Michele Guerini Rocco"
       meta ! charset "utf-8"
-      link ! rel "stylesheet" ! href "main.css" ! type_ "text/css"
-      link ! rel "apple-touch-icon" ! href "icon-big.png"
-      link ! rel "icon" ! type_ "image/png" ! href "/icon-medium.png" ! sizes "96x96"
-      link ! rel "icon" ! type_ "image/png" ! href "/icon-small.png" ! sizes "16x16"
-      script ! src "https://cdn.rawgit.com/LeaVerou/prefixfree/gh-pages/prefixfree.min.js" $ mempty
+      link ! rel "stylesheet" ! href "/static/main.css" ! type_ "text/css"
+      link ! rel "apple-touch-icon" ! href "static/icon-big.png"
+      link ! rel "icon" ! type_ "image/png" ! href "/static/icon-medium.png" ! sizes "96x96"
+      link ! rel "icon" ! type_ "image/png" ! href "/static/icon-small.png" ! sizes "16x16"
     body $ do
       header $ do
           h1 $ a ! href "/" $ "BREVE"
           h2 "a url shortener"
       H.div ! A.id "center" $ fill
       footer $ do
-          "breve is open "
-          a ! href "https://github.com/rnhmjoj/breve" $ "source"
-          H.span "© Rnhmjoj"
+          "breve is "
+          a ! href "https://maxwell.ydns.eu/git/rnhmjoj/breve" $ "free software"
+          H.span "© rnhmjoj"

static/main.css

@@ -1,5 +1,17 @@
-@import url(https://fonts.googleapis.com/css?family=Inconsolata:400,700);
-@import url(https://cdn.rawgit.com/necolas/normalize.css/master/normalize.css);
+@import url('normalize.css');
+
+@font-face {
+  font-family: Inconsolata;
+  src: local(Inconsolata),
+       url('inconsolata-regular.woff') format('woff');
+}
+
+@font-face {
+  font-family: Inconsolata;
+  font-weight: bold;
+  src: local(Inconsolata), local(Inconsolata Bold),
+       url('inconsolata-bold.woff') format('woff');
+}
 
 body {
     background-color: #181b20;

static/normalize.css

@@ -0,0 +1,349 @@
+/*! normalize.css v8.0.1 | MIT License | github.com/necolas/normalize.css */
+
+/* Document
+   ========================================================================== */
+
+/**
+ * 1. Correct the line height in all browsers.
+ * 2. Prevent adjustments of font size after orientation changes in iOS.
+ */
+
+html {
+  line-height: 1.15; /* 1 */
+  -webkit-text-size-adjust: 100%; /* 2 */
+}
+
+/* Sections
+   ========================================================================== */
+
+/**
+ * Remove the margin in all browsers.
+ */
+
+body {
+  margin: 0;
+}
+
+/**
+ * Render the `main` element consistently in IE.
+ */
+
+main {
+  display: block;
+}
+
+/**
+ * Correct the font size and margin on `h1` elements within `section` and
+ * `article` contexts in Chrome, Firefox, and Safari.
+ */
+
+h1 {
+  font-size: 2em;
+  margin: 0.67em 0;
+}
+
+/* Grouping content
+   ========================================================================== */
+
+/**
+ * 1. Add the correct box sizing in Firefox.
+ * 2. Show the overflow in Edge and IE.
+ */
+
+hr {
+  box-sizing: content-box; /* 1 */
+  height: 0; /* 1 */
+  overflow: visible; /* 2 */
+}
+
+/**
+ * 1. Correct the inheritance and scaling of font size in all browsers.
+ * 2. Correct the odd `em` font sizing in all browsers.
+ */
+
+pre {
+  font-family: monospace, monospace; /* 1 */
+  font-size: 1em; /* 2 */
+}
+
+/* Text-level semantics
+   ========================================================================== */
+
+/**
+ * Remove the gray background on active links in IE 10.
+ */
+
+a {
+  background-color: transparent;
+}
+
+/**
+ * 1. Remove the bottom border in Chrome 57-
+ * 2. Add the correct text decoration in Chrome, Edge, IE, Opera, and Safari.
+ */
+
+abbr[title] {
+  border-bottom: none; /* 1 */
+  text-decoration: underline; /* 2 */
+  text-decoration: underline dotted; /* 2 */
+}
+
+/**
+ * Add the correct font weight in Chrome, Edge, and Safari.
+ */
+
+b,
+strong {
+  font-weight: bolder;
+}
+
+/**
+ * 1. Correct the inheritance and scaling of font size in all browsers.
+ * 2. Correct the odd `em` font sizing in all browsers.
+ */
+
+code,
+kbd,
+samp {
+  font-family: monospace, monospace; /* 1 */
+  font-size: 1em; /* 2 */
+}
+
+/**
+ * Add the correct font size in all browsers.
+ */
+
+small {
+  font-size: 80%;
+}
+
+/**
+ * Prevent `sub` and `sup` elements from affecting the line height in
+ * all browsers.
+ */
+
+sub,
+sup {
+  font-size: 75%;
+  line-height: 0;
+  position: relative;
+  vertical-align: baseline;
+}
+
+sub {
+  bottom: -0.25em;
+}
+
+sup {
+  top: -0.5em;
+}
+
+/* Embedded content
+   ========================================================================== */
+
+/**
+ * Remove the border on images inside links in IE 10.
+ */
+
+img {
+  border-style: none;
+}
+
+/* Forms
+   ========================================================================== */
+
+/**
+ * 1. Change the font styles in all browsers.
+ * 2. Remove the margin in Firefox and Safari.
+ */
+
+button,
+input,
+optgroup,
+select,
+textarea {
+  font-family: inherit; /* 1 */
+  font-size: 100%; /* 1 */
+  line-height: 1.15; /* 1 */
+  margin: 0; /* 2 */
+}
+
+/**
+ * Show the overflow in IE.
+ * 1. Show the overflow in Edge.
+ */
+
+button,
+input { /* 1 */
+  overflow: visible;
+}
+
+/**
+ * Remove the inheritance of text transform in Edge, Firefox, and IE.
+ * 1. Remove the inheritance of text transform in Firefox.
+ */
+
+button,
+select { /* 1 */
+  text-transform: none;
+}
+
+/**
+ * Correct the inability to style clickable types in iOS and Safari.
+ */
+
+button,
+[type="button"],
+[type="reset"],
+[type="submit"] {
+  -webkit-appearance: button;
+}
+
+/**
+ * Remove the inner border and padding in Firefox.
+ */
+
+button::-moz-focus-inner,
+[type="button"]::-moz-focus-inner,
+[type="reset"]::-moz-focus-inner,
+[type="submit"]::-moz-focus-inner {
+  border-style: none;
+  padding: 0;
+}
+
+/**
+ * Restore the focus styles unset by the previous rule.
+ */
+
+button:-moz-focusring,
+[type="button"]:-moz-focusring,
+[type="reset"]:-moz-focusring,
+[type="submit"]:-moz-focusring {
+  outline: 1px dotted ButtonText;
+}
+
+/**
+ * Correct the padding in Firefox.
+ */
+
+fieldset {
+  padding: 0.35em 0.75em 0.625em;
+}
+
+/**
+ * 1. Correct the text wrapping in Edge and IE.
+ * 2. Correct the color inheritance from `fieldset` elements in IE.
+ * 3. Remove the padding so developers are not caught out when they zero out
+ *    `fieldset` elements in all browsers.
+ */
+
+legend {
+  box-sizing: border-box; /* 1 */
+  color: inherit; /* 2 */
+  display: table; /* 1 */
+  max-width: 100%; /* 1 */
+  padding: 0; /* 3 */
+  white-space: normal; /* 1 */
+}
+
+/**
+ * Add the correct vertical alignment in Chrome, Firefox, and Opera.
+ */
+
+progress {
+  vertical-align: baseline;
+}
+
+/**
+ * Remove the default vertical scrollbar in IE 10+.
+ */
+
+textarea {
+  overflow: auto;
+}
+
+/**
+ * 1. Add the correct box sizing in IE 10.
+ * 2. Remove the padding in IE 10.
+ */
+
+[type="checkbox"],
+[type="radio"] {
+  box-sizing: border-box; /* 1 */
+  padding: 0; /* 2 */
+}
+
+/**
+ * Correct the cursor style of increment and decrement buttons in Chrome.
+ */
+
+[type="number"]::-webkit-inner-spin-button,
+[type="number"]::-webkit-outer-spin-button {
+  height: auto;
+}
+
+/**
+ * 1. Correct the odd appearance in Chrome and Safari.
+ * 2. Correct the outline style in Safari.
+ */
+
+[type="search"] {
+  -webkit-appearance: textfield; /* 1 */
+  outline-offset: -2px; /* 2 */
+}
+
+/**
+ * Remove the inner padding in Chrome and Safari on macOS.
+ */
+
+[type="search"]::-webkit-search-decoration {
+  -webkit-appearance: none;
+}
+
+/**
+ * 1. Correct the inability to style clickable types in iOS and Safari.
+ * 2. Change font properties to `inherit` in Safari.
+ */
+
+::-webkit-file-upload-button {
+  -webkit-appearance: button; /* 1 */
+  font: inherit; /* 2 */
+}
+
+/* Interactive
+   ========================================================================== */
+
+/*
+ * Add the correct display in Edge, IE 10+, and Firefox.
+ */
+
+details {
+  display: block;
+}
+
+/*
+ * Add the correct display in all browsers.
+ */
+
+summary {
+  display: list-item;
+}
+
+/* Misc
+   ========================================================================== */
+
+/**
+ * Add the correct display in IE 10+.
+ */
+
+template {
+  display: none;
+}
+
+/**
+ * Add the correct display in IE 10.
+ */
+
+[hidden] {
+  display: none;
+}