Listing books

src/Database/Book.hs

@@ -0,0 +1,21 @@
+{-# Language TypeApplications #-}
+{-# Language DataKinds #-}
+module Database.Book (usersBooks, Book(..)) where
+
+import ClassyPrelude
+import Database.Schema
+import Database
+import Database.Selda
+
+usersBooks :: (MonadMask m, MonadIO m) => Username -> SeldaT m [Book]
+usersBooks username = fromRels <$> query q
+  where
+    q = do
+      userId :*: _ :*: username' :*: _ <- select (gen users)
+      userId' :*: bookHash' <- select (gen userBooks)
+      book@(bookHash :*: _) <- select (gen books)
+      restrict (bookHash .== bookHash')
+      restrict (username' .== literal username)
+      restrict (userId .== userId')
+      return book
+

src/Database/Channel.hs

@@ -3,6 +3,7 @@
 module Database.Channel
   ( userChannels
   , insertChannel
+  , booksChannels
   , Channel(..) )
   where
 
@@ -32,3 +33,13 @@ insertChannel username channel = do
       userId :*: _ :*: user :*: _ <- select (gen users)
       restrict (user .== literal username)
       return userId
+
+booksChannels :: (MonadMask m, MonadIO m) => HashDigest -> SeldaT m [Channel]
+booksChannels contentHash = fromRels <$> query q
+  where
+    q = do
+      channelId :*: contentHash' <- select (gen bookChannels)
+      ch@(channelId' :*: _) <- select (gen channels)
+      restrict (channelId .== channelId')
+      restrict (contentHash' .== literal contentHash)
+      return ch

src/Database/Schema.hs

@@ -83,15 +83,15 @@ instance SqlType HashDigest where
 books :: GenTable Book
 books = genTable "books" [ contentHash :- primaryGen ]
 
-data UserBook = UserBook { email :: Text
+data UserBook = UserBook { user :: RowID
                          , book :: HashDigest }
               deriving (Generic, Show)
 
 userBooks :: GenTable UserBook
-userBooks = genTable "user_book" [ (email :: UserBook -> Text) :- fkGen (gen users) userEmail
+userBooks = genTable "user_book" [ (user :: UserBook -> RowID) :- fkGen (gen users) userId
                                  , (book :: UserBook -> HashDigest) :- fkGen (gen books) bookHash ]
   where
-    _ :*: userEmail :*: _ = selectors (gen users)
+    userId :*: _ = selectors (gen users)
     bookHash :*: _ = selectors (gen books)
 
 -- | Categorizing books