Db layout, persistent-inst. & printer framework

3 files changed, 66 insertions, 1 deletions

diff --git a/server/src/Thermoprint/Server/Database.hs b/server/src/Thermoprint/Server/Database.hs
index 61179e6..65bfc37 100644
--- a/server/src/Thermoprint/Server/Database.hs
+++ b/server/src/Thermoprint/Server/Database.hs
@@ -11,13 +11,16 @@ module Thermoprint.Server.Database
        , migrateAll
        ) where
 
-import Thermoprint.API (Printout, DraftTitle)
+import Thermoprint.API (Printout, DraftTitle, JobStatus)
 
 import Database.Persist.TH
 
+import Thermoprint.Server.Database.Instances
+
 share [mkPersist sqlSettings, mkMigrate "migrateAll"] [persistLowerCase|
 Job
     content Printout
+    status JobStatus
 Draft
     title DraftTitle Maybe
     content Printout
diff --git a/server/src/Thermoprint/Server/Database/Instances.hs b/server/src/Thermoprint/Server/Database/Instances.hs
new file mode 100644
index 0000000..f5c22fd
--- /dev/null
+++ b/server/src/Thermoprint/Server/Database/Instances.hs
@@ -0,0 +1,33 @@
+{-# LANGUAGE TemplateHaskell            #-}
+{-# LANGUAGE TypeSynonymInstances       #-}
+{-# LANGUAGE FlexibleInstances          #-}
+
+module Thermoprint.Server.Database.Instances where
+
+import Thermoprint.API (Printout, JobStatus, PrintingError)
+
+import Database.Persist (PersistField(..))
+import Database.Persist.Sql (PersistFieldSql(..))
+import Database.Persist.TH
+
+import Control.Monad ((<=<))
+import Data.Bifunctor
+
+import qualified Data.Aeson as JSON (encode, eitherDecodeStrict')
+
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Lazy as LBS (toStrict)
+import qualified Data.Text as T (pack)
+
+import Data.Proxy
+
+-- | Instead of deriving an instance using 'derivePersistField', which would use 'show' and 'read', we write our own by hand in order to use json
+instance PersistField Printout where
+  toPersistValue   = toPersistValue . LBS.toStrict . JSON.encode
+  fromPersistValue = first T.pack . JSON.eitherDecodeStrict' <=< fromPersistValue
+
+instance PersistFieldSql Printout where
+  sqlType _ = sqlType (Proxy :: Proxy ByteString)
+
+derivePersistField "PrintingError"
+derivePersistField "JobStatus"
diff --git a/server/src/Thermoprint/Server/Printer.hs b/server/src/Thermoprint/Server/Printer.hs
new file mode 100644
index 0000000..e66afff
--- /dev/null
+++ b/server/src/Thermoprint/Server/Printer.hs
@@ -0,0 +1,29 @@
+{-# LANGUAGE RankNTypes #-}
+
+module Thermoprint.Server.Printer
+       ( Printer
+       ) where
+
+import Thermoprint.API (PrintingError(..), Printout)
+
+import Thermoprint.Server.Database
+
+import Database.Persist
+import Database.Persist.Sql
+
+import Data.Sequence (Seq, ViewL(..))
+import qualified Data.Sequence as Seq
+import Data.Map (Map)
+import qualified Data.Map as Map
+
+import Control.Monad.IO.Class (MonadIO)
+
+import Control.Concurrent.STM
+
+data Printer = Printer
+  { print :: forall m. (MonadIO m) => Printout -> m (Maybe PrintingError)
+  , queue :: TVar (Seq JobId)
+  }
+
+runPrinter :: Printer -> IO ()
+runPrinter = undefined