Updating channels (visibility)

- closes #13

migrations/V1.1__Channel_visibility.sql

@@ -0,0 +1 @@
+alter table channels add column visibility text NOT NULL default 'Private';

src/API/Books.hs

@@ -97,9 +97,9 @@ postBookMetaHandler auth PostBook{..} = flip requireLoggedIn auth $ \SafeUser{us
 
 
 putBookMetaHandler :: AuthResult SafeUser -> BookID -> JsonBook -> AppM JsonBook
-putBookMetaHandler auth bookId b@JsonBook{..}
+putBookMetaHandler auth bookId JsonBook{..}
   | bookId == identifier = requireBookOwner auth bookId $ \SafeUser{username=owner} ->
-        maybe (throwM err403) (const (return b)) =<< runDB (updateBook UpdateBook{..})
+        maybe (throwM err403) (return . view (super @JsonBook)) =<< runDB (updateBook UpdateBook{..})
   | otherwise = throwM err403
 
 listBooksHandler :: AuthResult SafeUser -> AppM [JsonBook]

src/API/Channels.hs

@@ -11,6 +11,8 @@
 {-# Language FlexibleInstances #-}
 {-# Language TypeApplications #-}
 {-# Language DataKinds #-}
+{-# Language DuplicateRecordFields #-}
+{-# Language NamedFieldPuns #-}
 module API.Channels (API, handler, JsonChannel(..)) where
 
 import Servant
@@ -25,18 +27,37 @@ import Data.Aeson
 import Control.Lens
 import Data.Generics.Product
 
-data JsonChannel = JsonChannel { channel :: Text } deriving (Show, Generic)
+data JsonChannel = JsonChannel { channel :: Text
+                               , visibility :: Visibility }
+                 deriving (Show, Generic)
+data UpdateChannel = UpdateChannel { identifier :: ChannelID
+                                   , channel :: Text
+                                   , visibility :: Visibility }
+                 deriving (Show, Generic)
 
 instance ToJSON JsonChannel
 instance FromJSON JsonChannel
+instance ToJSON UpdateChannel
+instance FromJSON UpdateChannel
 
 type API = Auth '[SA.BasicAuth, SA.Cookie, SA.JWT] SafeUser :> BaseAPI
 
-type BaseAPI = "channels" :> ReqBody '[JSON] JsonChannel :> Put '[JSON] JsonChannel
+type BaseAPI = "channels" :> ReqBody '[JSON] JsonChannel :> Post '[JSON] UpdateChannel
+          :<|> "channels" :> Capture "channel_id" ChannelID :> ReqBody '[JSON] UpdateChannel :> Put '[JSON] UpdateChannel
           :<|> "channels" :> Get '[JSON] [JsonChannel]
 
 handler :: ServerT API AppM
-handler user = newChannelHandler user :<|> listChannelsHandler user
+handler user = newChannelHandler user :<|> updateChannelHandler user :<|> listChannelsHandler user
+
+requireChannelOwner :: AuthResult SafeUser -> ChannelID -> (SafeUser -> AppM a) -> AppM a
+requireChannelOwner auth channelId f = flip requireLoggedIn auth $ \u@SafeUser{username} -> do
+  unlessM (runDB . channelExists $ channelId) $ throwM err404
+  runDB (isChannelOwner channelId username) >>= \o -> if o then f u else throwM err403
+
+updateChannelHandler :: AuthResult SafeUser -> ChannelID -> UpdateChannel -> AppM UpdateChannel
+updateChannelHandler auth channelId UpdateChannel{visibility} = requireChannelOwner auth channelId $ \_ -> do
+  mChannel <- fmap toChannel <$> runDB (updateChannelPrivacy channelId visibility)
+  maybe (throwM err403) return mChannel
 
 listChannelsHandler :: AuthResult SafeUser -> AppM [JsonChannel]
 listChannelsHandler = requireLoggedIn $ \user ->
@@ -44,8 +65,11 @@ listChannelsHandler = requireLoggedIn $ \user ->
   -- use the 'channel' accessor somehow or export it
   fmap (\Channel{..} -> JsonChannel{..}) <$> runDB (userChannels (view (field @"username") user))
 
-newChannelHandler :: AuthResult SafeUser -> JsonChannel -> AppM JsonChannel
-newChannelHandler auth ch@JsonChannel{..} = flip requireLoggedIn auth $ \user -> do
+newChannelHandler :: AuthResult SafeUser -> JsonChannel -> AppM UpdateChannel
+newChannelHandler auth JsonChannel{..} = flip requireLoggedIn auth $ \user -> do
   $logInfo $ "Creating channel for user " <> pack (show user)
-  runDB (insertChannel (view (field @"username") user) channel)
-  return ch
+  mChannel <- fmap toChannel <$> runDB (insertChannel (view (field @"username") user) channel visibility)
+  maybe (throwM err403{errBody="Could not create the channel"}) return mChannel
+
+toChannel :: Channel -> UpdateChannel
+toChannel Channel{..} = UpdateChannel{..}

src/Database/Book.hs

@@ -23,8 +23,11 @@ import Database
 import Database.Selda
 import Database.Selda.Generic
 
-import Database.Tag (attachTag, clearTags)
-import Database.Channel (attachChannel, clearChannels)
+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 username = fromRels <$> query q
@@ -70,6 +73,7 @@ data UpdateBook = UpdateBook { identifier :: BookID
                              , owner :: Username
                              , tags :: [Text]
                              , channels :: [Text] }
+                deriving (Show, Generic)
 
 bookExists :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> m Bool
 bookExists identifier = not . null <$> query q
@@ -92,23 +96,32 @@ bookOwner' identifier username = do
   return (userId :*: bookId)
 
 updateBook :: (MonadSelda m, MonadMask m, MonadIO m) => UpdateBook -> m (Maybe UpdateBook)
-updateBook book@UpdateBook{..} = do
+updateBook UpdateBook{..} = do
   clearTags identifier >> connectTags
   clearChannels identifier >> connectChannels
   updateBook'
+  getUpdateBook identifier owner
   where
     connectTags = mapM_ (attachTag owner identifier) tags
     connectChannels = mapM_ (attachChannel owner identifier) channels
     updateBook' = do
       mUserId <- query (bookOwner' identifier owner)
-      forM (listToMaybe mUserId) $ \_userId -> do
+      forM_ (listToMaybe mUserId) $ \_userId -> do
         update_ (gen books) predicate (\b -> b `with` [ pContentType := literal contentType
                                                       , pTitle := literal title
                                                       , pDescription := literal description ])
-        return book
     _ :*: _ :*: pContentType :*: pTitle :*: pDescription :*: _ = selectors (gen books)
     predicate (bookId :*: _) = bookId .== literal identifier
 
+
+getUpdateBook :: (MonadMask m, MonadIO m, MonadSelda m) => BookID -> Username -> m (Maybe UpdateBook)
+getUpdateBook bookId username = do
+  mBook <- getBook bookId username
+  forM mBook $ \Book{..} -> do
+    channels <- map (view (field @"channel")) <$> booksChannels bookId
+    tags <- map (view (field @"tag")) <$> booksTags bookId
+    return UpdateBook{owner=username,..}
+
 setContent :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> Username -> HashDigest -> m ()
 setContent identifier owner digest = do
   mOwner <- query (bookOwner' identifier owner)

src/Database/Channel.hs

@@ -4,7 +4,11 @@
 module Database.Channel
   ( userChannels
   , insertChannel
+  , channelExists
+  , isChannelOwner
+  , updateChannelPrivacy
   , attachChannel
+  , Visibility(..)
   , clearChannels
   , booksChannels
   , Channel(..)
@@ -17,29 +21,66 @@ import Database
 import Database.Selda
 import Database.Selda.Generic
 
+import Control.Monad.Trans.Maybe
+
+getChannel :: (MonadSelda m, MonadMask m, MonadIO m) => ChannelID -> m (Maybe Channel)
+getChannel identifier = listToMaybe . fromRels <$> query q
+  where
+    q = do
+      ch@(channelId :*: _) <- select (gen channels)
+      restrict (channelId .== literal identifier)
+      return ch
+
+channelExists :: (MonadSelda m, MonadMask m, MonadIO m) => ChannelID -> m Bool
+channelExists identifier = not . null <$> getChannel identifier
+
+isChannelOwner :: (MonadSelda m, MonadIO m, MonadMask m) => ChannelID -> Username -> m Bool
+isChannelOwner identifier username = not . null <$> query q
+  where
+    q = do
+      userId :*: _ :*: username' :*: _ <- select (gen users)
+      channelId :*: _ :*: channelOwner :*: _ <- select (gen channels)
+      restrict (userId .== channelOwner)
+      restrict (username' .== literal username)
+      restrict (channelId .== literal identifier)
+      return channelId
+
 userChannels :: (MonadMask m, MonadIO m) => Username -> SeldaT m [Channel]
 userChannels username = fromRels <$> query q
   where
     q = do
       userId :*: _ :*: username' :*: _ <- select (gen users)
-      channel@(_ :*: _ :*: owner) <- select (gen channels)
+      channel@(_ :*: _ :*: owner :*: _) <- select (gen channels)
       restrict (owner .== userId)
       restrict (username' .== literal username)
       return channel
 
-insertChannel :: (MonadMask m, MonadIO m) => Username -> Text -> SeldaT m ()
-insertChannel username channel = do
-  mUserId <- listToMaybe <$> getUser
-  void $ forM mUserId $ \userId ->
-    insertUnless (gen channels) (doesNotExist userId) [ def :*: channel :*: userId ]
+updateChannelPrivacy :: (MonadMask m, 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
   where
-    doesNotExist userId (_ :*: channel' :*: userId') = channel' .== literal channel .&& userId' .== literal userId
+    predicate (channelId' :*: _) = channelId' .== literal channelId
+    _ :*: _ :*: _ :*: pVis = selectors (gen channels)
+
+insertChannel :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> Text -> Visibility -> m (Maybe Channel)
+insertChannel username channel visibility = runMaybeT $ do
+  userId <- MaybeT (listToMaybe <$> getUser)
+  channelId <- toChannelId <$> MaybeT (insertUnless (gen channels) (doesNotExist userId) [ def :*: channel :*: userId :*: visibility ])
+  MaybeT (listToMaybe . fromRels <$> query (q channelId))
+  where
+    q channelId = do
+      ch@(channelId' :*: _) <- select (gen channels)
+      restrict (channelId' .== literal channelId)
+      return ch
+    toChannelId = ChannelID . fromRowId
+    doesNotExist userId (_ :*: channel' :*: userId' :*: _) = channel' .== literal channel .&& userId' .== literal userId
     getUser = query $ do
       userId :*: _ :*: user :*: _ <- select (gen users)
       restrict (user .== literal username)
       return userId
 
-booksChannels :: (MonadMask m, MonadIO m) => BookID -> SeldaT m [Channel]
+booksChannels :: (MonadSelda m, MonadMask m, MonadIO m) => BookID -> m [Channel]
 booksChannels bookId = fromRels <$> query q
   where
     q = do
@@ -51,8 +92,8 @@ booksChannels bookId = fromRels <$> query q
 
 attachChannel :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
 attachChannel username bookId channel = do
-  -- XXX: test what happens if channel doesn't exist
-  [Channel{identifier}] <- fromRels <$> query channelQ
+  mCh <- fromRels <$> query channelQ
+  forM_ mCh $ \Channel{identifier} ->
     whenM (null <$> query (attachQ identifier)) $
       void $ insertGen bookChannels [BookChannel identifier bookId]
   where
@@ -62,7 +103,7 @@ attachChannel username bookId channel = do
       return channelId'
     channelQ = do
       userId :*: _ :*: username' :*: _ <- select (gen users)
-      ch@(_ :*: channel' :*: owner) <- select (gen channels)
+      ch@(_ :*: channel' :*: owner :*: _) <- select (gen channels)
       restrict (username' .== literal username)
       restrict (owner .== userId)
       restrict (channel' .== literal channel)

src/Database/Schema.hs

@@ -44,7 +44,7 @@ newtype UserID = UserID {unUserID :: Int} deriving (Show)
 
 newtype BookID = BookID {unBookID :: Int} deriving (Show, ToJSON, FromJSON, FromHttpApiData, Eq, Ord)
 
-newtype ChannelID = ChannelID {unChannelID :: Int} deriving (Show, ToHttpApiData, FromHttpApiData)
+newtype ChannelID = ChannelID {unChannelID :: Int} deriving (Show, ToHttpApiData, FromHttpApiData, ToJSON, FromJSON)
 
 newtype TagID = TagID {unTagID :: Int} deriving (Show)
 
@@ -124,9 +124,22 @@ data Tag = Tag { identifier :: TagID
                , owner :: UserID }
          deriving (Show, Generic)
 
+data Visibility = Public | Private | Followers
+                deriving (Show, Read, Generic)
+
+instance ToJSON Visibility
+instance FromJSON Visibility
+
+instance SqlType Visibility where
+  mkLit = LCustom . LText . pack . show
+  fromSql (SqlString x) = fromMaybe (error "fromSql: Not a valid visibility token") . readMay . unpack $ x
+  fromSql _             = error "fromSql: Not a valid visibility token"
+  defaultValue = mkLit Private
+
 data Channel = Channel { identifier :: ChannelID
                        , channel :: Text
-                       , owner :: UserID }
+                       , owner :: UserID
+                       , visibility :: Visibility }
              deriving (Show, Generic)
 
 tags :: GenTable Tag

src/Database/Tag.hs

@@ -16,15 +16,13 @@ import Database.Schema
 import Database
 import Database.Selda
 import Database.Selda.Generic
+import Control.Monad.Trans.Maybe
 
-upsertTag :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> Text -> m Tag
-upsertTag username tag = do
-  -- I want this to error out if some data is invariant is wrong and roll back
-  -- the transaction. Also as a side note, run this in a transaction plz
-  [userId] <- query userQ
-  void $ upsert (gen tags) (predicate userId) id [toRel (Tag def tag userId)]
-  [t] <- fromRels <$> query (tagQ userId)
-  return t
+upsertTag :: (MonadMask 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)]
+  MaybeT (listToMaybe . fromRels <$> query (tagQ userId))
   where
     predicate userId (_ :*: tag' :*: owner) = tag' .== literal tag .&& owner .== literal userId
     tagQ userId = do
@@ -48,7 +46,8 @@ booksTags bookId = fromRels <$> query q
 
 attachTag :: (MonadMask m, MonadIO m, MonadSelda m) => Username -> BookID -> Text -> m ()
 attachTag username bookId tag = do
-  Tag{identifier} <- upsertTag username tag
+  maybeT <- upsertTag username tag
+  forM_ maybeT $ \Tag{identifier} -> do
     whenM (null <$> query (tagQ identifier)) $
       void $ insertGen bookTags [BookTag identifier bookId]
   where