wip

Suggestions for integrating the new migrations into the `withDBOpenFromFile` function

lib/wallet/src/Cardano/Wallet/DB/Layer.hs

@@ -387,6 +387,20 @@ withDBOpenFromFile
        -- ^ Action to run.
     -> IO a
 withDBOpenFromFile walletF tr defaultFieldValues dbFile action = do
+    let trDB = contramap MsgDB tr
+    runOldMigrations trDB dbFile defaultFieldValues
+    runMigrationSteps trDB dbFile $
+        newMigrations
+    withConnectionPool trDB dbFile $ \pool -> do
+        res <- newSqliteContext trDB pool [] (pure ())
+        case res of
+            Left err -> throwIO err
+            Right sqliteContext -> action =<< newQueryLock sqliteContext
+
+runOldMigrations
+    :: FilePath
+    -> IO ()
+runOldMigrations … dbFile = do
     let trDB = contramap MsgDB tr
     let manualMigrations =
             maybe [] (migrateManually trDB $ keyOfWallet walletF)
@@ -396,8 +410,7 @@ withDBOpenFromFile walletF tr defaultFieldValues dbFile action = do
         res <- newSqliteContext trDB pool manualMigrations autoMigrations
         case res of
             Left err -> throwIO err
-            Right sqliteContext -> action =<< newQueryLock sqliteContext
-
+            Right _ -> pure ()
 
 -- | Open an SQLite database in-memory.
 --

lib/wallet/src/Cardano/Wallet/DB/Migration.hs

@@ -70,12 +70,12 @@ instance Category (Migration m) where
     Migration s2 . Migration s1 = Migration (s1 <> s2)
 
 -- | Functions to interact with the database.
-data MigrationInterface m handle = MigrationInterface
-    { backupDatabaseFile :: FilePath -> Version -> m ()
+data MigrationInterface m filePath handle = MigrationInterface
+    { backupDatabaseFile :: filePath -> Version -> m ()
         -- ^ Back up the (closed) database file.
         -- The 'Version' argument can be used to find a new file path
         -- for the backup copy.
-    , withDatabaseFile :: forall r. FilePath -> (handle -> m r) -> m r
+    , withDatabaseFile :: forall r. filePath -> (handle -> m r) -> m r
         -- ^ Open a database file and close it after use or on exception.
     , getVersion :: handle -> m Version
         -- ^ Get the current version.

lib/wallet/src/Cardano/Wallet/DB/Sqlite/MigrationNew.hs

@@ -0,0 +1,26 @@
+{-
+
+1. implement
+
+    mkMigrationInterfaceFile
+        :: MigrationInterface IO FilePath Sqlite.Connection
+
+    Duplicate raw SQL statements form `getVersion` and `setVersion`
+
+        withDatabaseFile = do
+            …
+            withConnectionPool $ \pool ->
+                …
+
+2. implement
+
+    newMigrationInterfaceInMemory
+        :: Sqlite.Connection
+        -> MigrationInterface IO () Sqlite.Connection
+
+        backupDatabaseFile = nop
+        withDatabaseFile = \_ -> …
+            -- in memory,
+            -- do not close the database context on exiting this function
+
+-}