Start working on multiple data backends

- Closes #28

.gitignore

@@ -1,2 +1,6 @@
 dist/
 config/config.dhall
+/ctags
+/TAGS
+/result*
+/backend/config

backend/ChangeLog.md

@@ -0,0 +1,5 @@
+# Revision history for backend
+
+## 0.1.0.0 -- YYYY-mm-dd
+
+* First version. Released on an unsuspecting world.

backend/LICENSE

@@ -0,0 +1,30 @@
+Copyright (c) 2018, Mats Rauhala
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Mats Rauhala nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

backend/Setup.hs

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

backend/backend.cabal

@@ -1,4 +1,7 @@
-name:                ebook-manager
+-- Initial backend.cabal generated by cabal init.  For further
+-- documentation, see http://haskell.org/cabal/users-guide/
+
+name:                backend
 version:             0.1.0.0
 -- synopsis:
 -- description:
@@ -12,7 +15,7 @@ build-type:          Simple
 extra-source-files:  ChangeLog.md
 cabal-version:       >=1.10
 
-executable ebook-manager
+executable backend
   main-is:             Main.hs
   other-modules:       Devel.Main
                      , API
@@ -20,8 +23,6 @@ executable ebook-manager
                      , API.Catalogue
                      , API.Channels
                      , API.Users
-                     , Configuration
-                     , Data.Versioned
                      , Database
                      , Database.Book
                      , Database.Channel
@@ -35,7 +36,10 @@ executable ebook-manager
                      , Types
                      , View
   -- other-extensions:
-  build-depends:       base >=4.10 && <4.11
+  build-depends:       base >=4.10
+                     , exceptions
+                     , monad-control
+                     , common
                      , aeson
                      , asn1-data
                      , asn1-types
@@ -77,8 +81,8 @@ executable ebook-manager
                      , xml-conduit
                      , xml-hamlet
   hs-source-dirs:      src
+  default-language:    Haskell2010
   default-extensions:  DeriveGeneric
                      , NoImplicitPrelude
                      , OverloadedStrings
                      , RecordWildCards
-  default-language:    Haskell2010

backend/src/API/Books.hs

@@ -15,24 +15,25 @@
 {-# Language NamedFieldPuns #-}
 module API.Books where
 
-import Servant hiding (contentType)
-import Types
-import ClassyPrelude
-import Server.Auth
-import Servant.Auth as SA
-import Data.Aeson
-import Database.Book
-import Database.Channel
-import Database.Tag
-import Database
-import Control.Lens
-import Data.Generics.Product
+import           ClassyPrelude
+import           Control.Lens
+import           Control.Monad.Catch (throwM, MonadThrow)
+import           Data.Aeson
+import           Data.Generics.Product
+import           Database
+import           Database.Book
+import           Database.Channel
+import           Database.Tag
+import           Servant hiding (contentType)
+import           Servant.Auth as SA
+import           Server.Auth
+import           Types
 
-import Control.Monad.Trans.Maybe
+import           Control.Monad.Trans.Maybe
 
 import qualified Datastore as DS
-import Data.ByteArray (convert)
-import Crypto.Hash (digestFromByteString)
+import           Data.ByteArray (convert)
+import           Crypto.Hash (digestFromByteString)
 
 data JsonBook = JsonBook { identifier :: BookID
                          , contentType :: Text

backend/src/API/Catalogue.hs

@@ -16,17 +16,17 @@
 {-# Language ScopedTypeVariables #-}
 module API.Catalogue (VersionedAPI, handler) where
 
-import Types
-import Servant hiding (contentType)
-import ClassyPrelude
-import GHC.TypeLits
-import Server.Auth
-import Servant.Auth as SA
-import Servant.XML
-import qualified Database.Channel as Channel
-import Database.Book (Book(..))
-import Database
 import qualified API.Books
+import           ClassyPrelude
+import           Database
+import           Database.Book (Book(..))
+import qualified Database.Channel as Channel
+import           GHC.TypeLits
+import           Servant hiding (contentType)
+import           Servant.Auth as SA
+import           Servant.XML
+import           Server.Auth
+import           Types
 
 -- This is my first try on going to versioned apis, things might change
 -- I think my rule of thumb is that you can add new things as you want, but

backend/src/API/Channels.hs

@@ -15,17 +15,18 @@
 {-# Language NamedFieldPuns #-}
 module API.Channels (API, handler, JsonChannel(..)) where
 
-import Servant
-import Types
 import ClassyPrelude
-import Server.Auth
-import Servant.Auth as SA
+import Control.Lens
+import Control.Monad.Catch (throwM, MonadThrow)
 import Control.Monad.Logger
+import Data.Aeson
+import Data.Generics.Product
 import Database
 import Database.Channel
-import Data.Aeson
-import Control.Lens
-import Data.Generics.Product
+import Servant
+import Servant.Auth as SA
+import Server.Auth
+import Types
 
 data JsonChannel = JsonChannel { channel :: Text
                                , visibility :: Visibility }

backend/src/API/Users.hs

@@ -7,17 +7,18 @@
 {-# Language TypeApplications #-}
 module API.Users  where
 
-import Servant
 import ClassyPrelude
-import Types
+import Control.Monad.Catch (throwM, MonadThrow)
 import Data.Aeson
-import Web.FormUrlEncoded
 import Database (runDB)
-import Database.User
 import Database.Schema
-import Server.Auth
-import Servant.Auth.Server as SAS
+import Database.User
+import Servant
 import Servant.Auth as SA
+import Servant.Auth.Server as SAS
+import Server.Auth
+import Types
+import Web.FormUrlEncoded
 
 
 data RegisterForm = RegisterForm { username :: Username

backend/src/Database.hs

@@ -15,15 +15,17 @@ module Database
   , SeldaT )
   where
 
-import Data.Generics.Product
-import Control.Lens (view)
-import Data.Pool (Pool, withResource)
-import Database.Selda.Backend (SeldaConnection, runSeldaT, SeldaT)
-import Database.Selda (query, select, transaction)
-import Database.Selda.Generic (gen, fromRel, fromRels, toRel)
 import ClassyPrelude
+import Control.Lens (view)
+import Control.Monad.Catch (MonadMask)
+import Control.Monad.Trans.Control (MonadBaseControl)
+import Data.Generics.Product
+import Data.Pool (Pool, withResource)
+import Database.Selda (query, select, transaction)
+import Database.Selda.Backend (SeldaConnection, runSeldaT, SeldaT)
+import Database.Selda.Generic (gen, fromRel, fromRels, toRel)
 
-type DBLike r m = (MonadIO m, MonadReader r m, MonadBaseControl IO m, MonadMask m, HasField' "database" r (Pool SeldaConnection))
+type DBLike r m = (MonadBaseControl IO m, MonadIO m, MonadReader r m, HasField "database" r r (Pool SeldaConnection) (Pool SeldaConnection), MonadMask m)
 
 runDB :: DBLike r m => SeldaT m a -> m a
 runDB q = do

backend/src/Database/Book.hs

@@ -18,18 +18,17 @@ module Database.Book
   , BookID) where
 
 import ClassyPrelude
-import Database.Schema (books, users, Username, Book(..), BookID(..), UserID, HashDigest(..))
+import Control.Lens (view)
+import Control.Monad.Catch (MonadCatch)
+import Data.Generics.Product
 import Database
+import Database.Channel (booksChannels, attachChannel, clearChannels)
+import Database.Schema (books, users, Username, Book(..), BookID(..), UserID, HashDigest(..))
 import Database.Selda
 import Database.Selda.Generic
-
-import Control.Lens (view)
-import Data.Generics.Product
-
 import Database.Tag (booksTags, attachTag, clearTags)
-import Database.Channel (booksChannels, attachChannel, clearChannels)
 
-usersBooks :: (MonadSelda m, MonadMask m, MonadIO m) => Username -> m [Book]
+usersBooks :: (MonadSelda m, MonadIO m) => Username -> m [Book]
 usersBooks username = fromRels <$> query q
   where
     q = do
@@ -41,7 +40,7 @@ usersBooks username = fromRels <$> query q
       return book
 
 
-getBook :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> Username -> m (Maybe Book)
+getBook :: (MonadSelda m, MonadIO m) => BookID -> Username -> m (Maybe Book)
 getBook identifier owner = listToMaybe . fromRels <$> query q
   where
     q = do
@@ -56,7 +55,7 @@ data InsertBook = InsertBook { contentType :: Text
                              , owner :: Username }
 
 -- Always inserts
-insertBook :: (MonadSelda m, MonadMask m, MonadIO m) => InsertBook -> m (Maybe BookID)
+insertBook :: (MonadSelda m, MonadIO m) => InsertBook -> m (Maybe BookID)
 insertBook InsertBook{..} = do
   mUserId <- query $ do
     userId :*: _ :*: username' :*: _ <- select (gen users)
@@ -75,7 +74,7 @@ data UpdateBook = UpdateBook { identifier :: BookID
                              , channels :: [Text] }
                 deriving (Show, Generic)
 
-bookExists :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> m Bool
+bookExists :: (MonadSelda m, MonadIO m) => BookID -> m Bool
 bookExists identifier = not . null <$> query q
   where
     q = do
@@ -83,7 +82,7 @@ bookExists identifier = not . null <$> query q
       restrict (bookId .== literal identifier)
       return bookId
 
-isBookOwner :: (MonadSelda m, MonadIO m, MonadThrow m) => BookID -> Username -> m Bool
+isBookOwner :: (MonadSelda m, MonadIO m) => BookID -> Username -> m Bool
 isBookOwner identifier username = not . null <$> query (bookOwner' identifier username)
 
 bookOwner' :: BookID -> Username -> Query s (Col s UserID :*: Col s BookID)
@@ -95,7 +94,7 @@ bookOwner' identifier username = do
   restrict (bookId .== literal identifier)
   return (userId :*: bookId)
 
-updateBook :: (MonadSelda m, MonadMask m, MonadIO m) => UpdateBook -> m (Maybe UpdateBook)
+updateBook :: (MonadCatch m, MonadSelda m, MonadIO m) => UpdateBook -> m (Maybe UpdateBook)
 updateBook UpdateBook{..} = do
   clearTags identifier >> connectTags
   clearChannels identifier >> connectChannels
@@ -114,7 +113,7 @@ updateBook UpdateBook{..} = do
     predicate (bookId :*: _) = bookId .== literal identifier
 
 
-getUpdateBook :: (MonadMask m, MonadIO m, MonadSelda m) => BookID -> Username -> m (Maybe UpdateBook)
+getUpdateBook :: (MonadIO m, MonadSelda m) => BookID -> Username -> m (Maybe UpdateBook)
 getUpdateBook bookId username = do
   mBook <- getBook bookId username
   forM mBook $ \Book{..} -> do
@@ -122,7 +121,7 @@ getUpdateBook bookId username = do
     tags <- map (view (field @"tag")) <$> booksTags bookId
     return UpdateBook{owner=username,..}
 
-setContent :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> Username -> HashDigest -> m ()
+setContent :: (MonadSelda m, MonadIO m) => BookID -> Username -> HashDigest -> m ()
 setContent identifier owner digest = do
   mOwner <- query (bookOwner' identifier owner)
   void $ forM (listToMaybe mOwner) $ \_ ->

backend/src/Database/Channel.hs

@@ -17,14 +17,15 @@ module Database.Channel
   where
 
 import ClassyPrelude
-import Database.Schema
+import Control.Monad.Catch (MonadMask)
 import Database
+import Database.Schema
 import Database.Selda
 import Database.Selda.Generic
 
 import Control.Monad.Trans.Maybe
 
-getChannel :: (MonadSelda m, MonadMask m, MonadIO m) => ChannelID -> m (Maybe Channel)
+getChannel :: (MonadSelda m, MonadIO m) => ChannelID -> m (Maybe Channel)
 getChannel identifier = listToMaybe . fromRels <$> query q
   where
     q = do
@@ -32,10 +33,10 @@ getChannel identifier = listToMaybe . fromRels <$> query q
       restrict (channelId .== literal identifier)
       return ch
 
-channelExists :: (MonadSelda m, MonadMask m, MonadIO m) => ChannelID -> m Bool
+channelExists :: (MonadSelda m, MonadIO m) => ChannelID -> m Bool
 channelExists identifier = not . null <$> getChannel identifier
 
-isChannelOwner :: (MonadSelda m, MonadIO m, MonadMask m) => ChannelID -> Username -> m Bool
+isChannelOwner :: (MonadSelda m, MonadIO m) => ChannelID -> Username -> m Bool
 isChannelOwner identifier username = not . null <$> query q
   where
     q = do
@@ -56,7 +57,7 @@ userChannels username = fromRels <$> query q
       restrict (username' .== literal username)
       return channel
 
-updateChannelPrivacy :: (MonadMask m, MonadIO m, MonadSelda m) => ChannelID -> Visibility -> m (Maybe Channel)
+updateChannelPrivacy :: (MonadIO m, MonadSelda m) => ChannelID -> Visibility -> m (Maybe Channel)
 updateChannelPrivacy channelId visibility = do
   void $ update (gen channels) predicate (\channel -> channel `with` [pVis := literal visibility])
   getChannel channelId
@@ -81,7 +82,7 @@ insertChannel username channel visibility = runMaybeT $ do
       restrict (user .== literal username)
       return userId
 
-channelBooks :: (MonadSelda m, MonadMask m, MonadIO m) => Username -> ChannelID -> m [Book]
+channelBooks :: (MonadSelda m, MonadIO m) => Username -> ChannelID -> m [Book]
 channelBooks username identifier = fromRels <$> query q
   where
     q = do
@@ -94,7 +95,7 @@ channelBooks username identifier = fromRels <$> query q
       restrict (bookId .== bookId')
       return book
 
-booksChannels :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> m [Channel]
+booksChannels :: (MonadSelda m, MonadIO m) => BookID -> m [Channel]
 booksChannels bookId = fromRels <$> query q
   where
     q = do
@@ -104,7 +105,7 @@ booksChannels bookId = fromRels <$> query q
       restrict (bookId' .== literal bookId)
       return ch
 
-attachChannel :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
+attachChannel :: (MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
 attachChannel username bookId channel = do
   mCh <- fromRels <$> query channelQ
   forM_ mCh $ \Channel{identifier} ->
@@ -123,5 +124,5 @@ attachChannel username bookId channel = do
       restrict (channel' .== literal channel)
       return ch
 
-clearChannels :: (MonadMask m, MonadIO m, MonadSelda m) => BookID -> m Int
+clearChannels :: (MonadIO m, MonadSelda m) => BookID -> m Int
 clearChannels bookId = deleteFrom (gen bookChannels) (\(_ :*: bookId') -> bookId' .== literal bookId)

backend/src/Database/Tag.hs

@@ -12,13 +12,14 @@ module Database.Tag
   , Tag(..) ) where
 
 import ClassyPrelude
-import Database.Schema
+import Control.Monad.Catch (MonadCatch)
+import Control.Monad.Trans.Maybe
 import Database
+import Database.Schema
 import Database.Selda
 import Database.Selda.Generic
-import Control.Monad.Trans.Maybe
 
-upsertTag :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> Text -> m (Maybe Tag)
+upsertTag :: (MonadCatch m, MonadIO m, MonadSelda m) => Username -> Text -> m (Maybe Tag)
 upsertTag username tag = runMaybeT $ do
   userId <- MaybeT (listToMaybe <$> query userQ)
   void $ lift $ upsert (gen tags) (predicate userId) id [toRel (Tag def tag userId)]
@@ -34,7 +35,7 @@ upsertTag username tag = runMaybeT $ do
       restrict (username' .== literal username)
       return userId
 
-booksTags :: (MonadMask m, MonadIO m, MonadSelda m) => BookID -> m [Tag]
+booksTags :: (MonadIO m, MonadSelda m) => BookID -> m [Tag]
 booksTags bookId = fromRels <$> query q
   where
     q = do
@@ -44,7 +45,7 @@ booksTags bookId = fromRels <$> query q
       restrict (bookId' .== literal bookId)
       return tag
 
-attachTag :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
+attachTag :: (MonadCatch m, MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
 attachTag username bookId tag = do
   maybeT <- upsertTag username tag
   forM_ maybeT $ \Tag{identifier} -> do
@@ -56,6 +57,6 @@ attachTag username bookId tag = do
       restrict (tagId' .== literal tagId .&& bookId' .== literal bookId)
       return tagId'
 
-clearTags :: (MonadMask m, MonadIO m, MonadSelda m) => BookID -> m Int
+clearTags :: (MonadIO m, MonadSelda m) => BookID -> m Int
 clearTags bookId = deleteFrom (gen bookTags) (\(_ :*: bookId') -> bookId' .== literal bookId)
 

backend/src/Database/User.hs

@@ -5,20 +5,21 @@
 module Database.User where
 
 import ClassyPrelude
+import Control.Lens (view, over, _Just)
+import Control.Monad (mfilter)
+import Control.Monad.Catch (MonadMask)
+import Control.Monad.Logger
+import Crypto.KDF.BCrypt
+import Crypto.Random.Types (MonadRandom)
+import Data.Generics.Product
 import Database
 import Database.Schema
 import Database.Selda
-import Control.Lens (view, over, _Just)
-import Data.Generics.Product
-import Crypto.KDF.BCrypt
-import Crypto.Random.Types (MonadRandom)
-import Control.Monad.Logger
-import Control.Monad (mfilter)
 
 data UserExistsError = UserExistsError
 
 
-insertUser :: (MonadLogger m, MonadIO m, MonadMask m, MonadRandom m) => Username -> Email -> PlainPassword -> SeldaT m (Either UserExistsError (User NoPassword))
+insertUser :: (MonadMask m, MonadLogger m, MonadIO m, MonadRandom m) => Username -> Email -> PlainPassword -> SeldaT m (Either UserExistsError (User NoPassword))
 insertUser username email (PlainPassword password) =
   getUser' username >>= maybe insert' (const (return $ Left UserExistsError))
   where

backend/src/Datastore.hs

@@ -5,6 +5,7 @@
 {-# Language FlexibleContexts #-}
 {-# Language TypeSynonymInstances #-}
 {-# Language FlexibleInstances #-}
+{-# Language ScopedTypeVariables #-}
 module Datastore where
 
 import ClassyPrelude
@@ -28,26 +29,26 @@ instance MonadDS AppM where
   get = getLocal
 
 putLocal :: ( MonadIO m
-            , HasField' "config" r config
-            , HasField' "store" config store
-            , HasField' "path" store Text
+            , HasField "config" r r config config
+            , HasField "store" config config store store
+            , HasType Text store
             , MonadReader r m)
             => ByteString -> m (Digest SHA256)
 putLocal bs = do
-  store <- unpack <$> view (field @"config" . field @"store" . field @"path")
+  store :: FilePath <- unpack <$> view (field @"config" . field @"store" . typed @Text)
   liftIO $ createDirectoryIfMissing True store
   let key = hashWith SHA256 bs
   writeFile (store </> show key) bs
   return key
 
 getLocal :: ( MonadIO m
-            , HasField' "config" r config
-            , HasField' "store" config store
-            , HasField' "path" store Text
+            , HasField "config" r r config config
+            , HasField "store" config config store store
+            , HasType Text store
             , MonadReader r m)
             => Digest SHA256 -> m (Maybe ByteString)
 getLocal key = do
-  store <- unpack <$> view (field @"config" . field @"store" . field @"path")
+  store <- unpack <$> view (field @"config" . field @"store" . typed @Text)
   liftIO $ createDirectoryIfMissing True store
   let file = store </> show key
   exists <- liftIO $ doesFileExist file

backend/src/Devel/Main.hs

@@ -3,19 +3,18 @@
 {-# Language FlexibleContexts #-}
 module Devel.Main where
 
-import Prelude
-import Control.Monad.Trans.Reader (runReaderT)
-import Main (withApp, defaultMain)
 import Control.Concurrent
 import Control.Monad (void)
+import Control.Monad.Trans.Reader (runReaderT)
 import Data.IORef (IORef, newIORef, readIORef, writeIORef)
-import Foreign.Store (Store(..), lookupStore, readStore, storeAction, withStore)
-import GHC.Word (Word32)
-import Dhall (input, auto)
-
+import Database
 import Database.Schema
 import Database.Selda (tryCreateTable)
-import Database
+import Dhall (input, auto)
+import Foreign.Store (Store(..), lookupStore, readStore, storeAction, withStore)
+import GHC.Word (Word32)
+import Main (withApp, defaultMain)
+import Prelude
 
 update :: IO ()
 update = do
@@ -37,7 +36,7 @@ update = do
 
 develMain :: IO ()
 develMain = do
-  conf <- input auto "./config/devel.dhall"
+  conf <- input auto "../config/devel.dhall"
   withApp conf $ \app -> do
     void $ runReaderT (runDB migrate) app
     defaultMain app

backend/src/Main.hs

@@ -25,6 +25,7 @@ withApp :: Config -> (App -> IO ()) -> IO ()
 withApp config f = do
   let pgHost = view (field @"database" . field @"host") config
       pgPort = 5432
+      pgSchema = Nothing
       pgDatabase = view (field @"database" . field @"database") config
       pgUsername = Just (view (field @"database" . field @"username") config)
       pgPassword = Just (view (field @"database" . field @"password") config)

backend/src/Server.hs

@@ -10,6 +10,7 @@
 {-# Language DeriveGeneric #-}
 {-# Language FlexibleInstances #-}
 {-# Language TypeApplications #-}
+{-# Language ScopedTypeVariables #-}
 module Server where
 
 import qualified API as API
@@ -22,19 +23,21 @@ import Control.Monad.Except
 import Servant.Auth.Server as SAS
 import Control.Lens
 import Data.Generics.Product
+import Server.Auth (SafeUser)
 
 type API = API.API :<|> "static" :> Raw
 
+type Ctx = '[BasicAuthData -> IO (AuthResult SafeUser), CookieSettings, JWTSettings]
 
 server :: App -> Application
-server app = serveWithContext api cfg (enter server' API.handler :<|> serveDirectoryFileServer "static")
+server app = serveWithContext api cfg (hoistServerWithContext (Proxy @ API.API) (Proxy @ Ctx) server' API.handler :<|> serveDirectoryFileServer "static")
   where
     myKey = view (field @"jwk") app
     jwtCfg = defaultJWTSettings myKey
     authCfg = authCheck app
     cookieSettings = SAS.defaultCookieSettings{cookieIsSecure=SAS.NotSecure}
     cfg = jwtCfg :. cookieSettings :. authCfg :. EmptyContext
-    server' :: AppM :~> Servant.Handler
-    server' = NT (Handler . ExceptT . try . (`runReaderT` app) . (runFileLoggingT "logs/server.log"))
+    server' :: AppM a -> Servant.Handler a
+    server' = Handler . ExceptT . try . (`runReaderT` app) . (runFileLoggingT "logs/server.log")
     api :: Proxy API
     api = Proxy

backend/src/Server/Auth.hs

@@ -14,16 +14,17 @@ module Server.Auth
   where
 
 import ClassyPrelude
-import Servant.Auth.Server as SAS
+import Control.Lens (view)
+import Control.Monad.Logger
+import Control.Monad.Catch (throwM, MonadThrow)
 import Data.Aeson
+import Data.Generics.Product
+import Database
 import Database.Schema
 import Database.User
-import Database
-import Types
-import Control.Lens (view)
-import Data.Generics.Product
 import Servant (err401)
-import Control.Monad.Logger
+import Servant.Auth.Server as SAS
+import Types
 
 -- generic-lens can convert similar types to this
 -- I'm trying out servant-auth-server which uses a jwt style login. IIRC anyone
@@ -53,6 +54,6 @@ authCheck app (BasicAuthData username password) = flip runReaderT app $
     password' = PlainPassword $ decodeUtf8 password
     authenticated = SAS.Authenticated . view (super @SafeUser)
 
-requireLoggedIn :: (MonadLogger m, MonadThrow m, Monad m) => (SafeUser -> m a) -> AuthResult SafeUser -> m a
+requireLoggedIn :: (MonadThrow m, MonadLogger m, Monad m) => (SafeUser -> m a) -> AuthResult SafeUser -> m a
 requireLoggedIn f (Authenticated user) = f user
 requireLoggedIn _ u = $logError (pack (show u)) >> throwM err401

common/LICENSE

@@ -0,0 +1,30 @@
+Copyright (c) 2018, Mats Rauhala
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Mats Rauhala nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

common/common.cabal

@@ -0,0 +1,33 @@
+name:                common
+version:             0.1.0.0
+-- synopsis:
+-- description:
+license:             BSD3
+license-file:        LICENSE
+author:              Mats Rauhala
+maintainer:          mats.rauhala@iki.fi
+-- copyright:
+category:            Web
+build-type:          Simple
+extra-source-files:  ChangeLog.md
+cabal-version:       >=1.10
+
+library
+  exposed-modules:     Configuration
+                     , Data.Versioned
+  -- other-extensions:
+  build-depends:       base >=4.10
+                     , classy-prelude
+                     , dhall
+                     , foreign-store
+                     , generic-lens
+                     , lens
+                     , mtl
+                     , text
+                     , transformers
+  hs-source-dirs:      src
+  default-extensions:  DeriveGeneric
+                     , NoImplicitPrelude
+                     , OverloadedStrings
+                     , RecordWildCards
+  default-language:    Haskell2010

common/src/Configuration.hs

@@ -12,7 +12,9 @@ data Pg = Pg { username :: Text
              , database :: Text }
         deriving (Show, Generic)
 
-newtype Store = Store { path :: Text } deriving (Show, Generic)
+data Store = Filestore { path :: Text }
+           | IPFS { common :: Text }
+           deriving (Show, Generic)
 
 data Config = Config { database :: Pg
                      , store :: Store }

default.nix

@@ -1,10 +1,15 @@
-{ mkDerivation, base, stdenv }:
-mkDerivation {
-  pname = "ebook-manager";
-  version = "0.1.0.0";
-  src = ./.;
-  isLibrary = false;
-  isExecutable = true;
-  executableHaskellDepends = [ base ];
-  license = stdenv.lib.licenses.bsd3;
+{ nixpkgs, haskellPackages }:
+
+(import ./project.nix nixpkgs) {
+  packages = {
+    common = ./common;
+    backend = ./backend;
+  };
+  overrides = self: super: {
+    generic-lens = nixpkgs.haskell.lib.dontCheck super.generic-lens;
+  };
+  tools = with haskellPackages; [
+    ghcid
+    hasktags
+  ];
 }

nixpkgs-version.json

@@ -1,7 +1,7 @@
 {
   "url": "https://github.com/nixos/nixpkgs.git",
-  "rev": "83a5765b1fea2472ec9cf9d179d3efd18b45c77e",
+  "rev": "e0d250e5cf6d179e1ccc775472d89718f61fcfd1",
   "date": "2018-01-08T11:52:28+01:00",
-  "sha256": "01rb61dkbzjbwnb3p8lgs03a94f4584199dlr0cwdmqzaxnp506h",
+  "sha256": "1iqpjz4czcpghbv924a5h4jvfmj6c8q6sl3b1z7blz3mi740aivs",
   "fetchSubmodules": true
 }

project.nix

@@ -0,0 +1,39 @@
+nixpkgs:
+
+let
+
+  inherit (nixpkgs.lib) mapAttrs mapAttrsToList escapeShellArg optionalString concatStringsSep concatMapStringsSep;
+
+in
+
+{ packages
+, overrides ? _ : _ : {}
+, tools ? []
+}:
+
+let
+
+  overrides' = nixpkgs.lib.foldr nixpkgs.lib.composeExtensions (_: _: {}) [
+    (self: super: mapAttrs (name: path: self.callCabal2nix name path {}) packages)
+    overrides
+  ];
+  haskellPackages = nixpkgs.haskellPackages.override { overrides = overrides'; };
+  packages' = mapAttrs (name: _: haskellPackages."${name}") packages;
+  mkShell = name: pkg:
+  let
+    n =  "${name}-shell";
+    deps = haskellPackages.ghcWithHoogle (pkgs: pkg.buildInputs ++ pkg.propagatedBuildInputs);
+  in
+  {
+    name = "${n}";
+    value = nixpkgs.buildEnv {
+      name = "${n}";
+      paths = tools;
+      buildInputs = tools ++ [deps];
+    };
+  };
+  shells = nixpkgs.lib.listToAttrs (mapAttrsToList mkShell packages');
+
+in
+
+packages' // shells

release.nix

@@ -0,0 +1,15 @@
+{ nixpkgs ? import <nixpkgs> {} }:
+
+let
+
+  pinnedVersion = nixpkgs.lib.importJSON ./nixpkgs-version.json;
+  pinnedPkgs = import (nixpkgs.fetchFromGitHub {
+    owner = "NixOS";
+    repo = "nixpkgs";
+    inherit (pinnedVersion) rev sha256;
+  }) {};
+  inherit (pinnedPkgs) pkgs;
+
+  in
+
+import ./default.nix { nixpkgs = pinnedPkgs; haskellPackages = pinnedPkgs.haskellPackages; }