[WIP] Allow Jennifer::Migration::Runner.migrate to specify an adapter.

src/jennifer/migration/runner.cr

@@ -3,25 +3,25 @@ module Jennifer
     # This modules is responsible for processing database migration operations like creation,
     # dropping and migration.
     module Runner
-      @@pending_versions = [] of String
-
       # Invokes migrations. *count* with negative or zero value will invoke all pending migrations.
-      def self.migrate(count : Int = -1)
+      def self.migrate(count : Int = -1, adapter : Adapter::Base = default_adapter)
         performed = false
-        default_adapter.ready_to_migrate!
-        return unless pending_migration?
+        Version.adapter = adapter
+        adapter.ready_to_migrate!
+        pending_versions = get_pending_versions
+        return if pending_versions.empty?
 
-        assert_outdated_pending_migrations
+        assert_outdated_pending_migrations pending_versions
         migrations = Base.migrations
 
         pending_versions.each_with_index do |version, i|
           return if count > 0 && i >= count
 
-          process_up_migration(migrations[version].new)
+          process_up_migration(migrations[version].new, adapter)
           performed = true
         end
       ensure
-        default_adapter.generate_schema if performed && !Config.skip_dumping_schema_sql
+        adapter.generate_schema if performed && !adapter.config.skip_dumping_schema_sql
       end
 
       # Creates database using given *adapter*.
@@ -51,9 +51,9 @@ module Jennifer
       # Allowed options:
       # - *count* - count of migrations to be rolled back
       # - *to* - migration timestamp to which database should be rolled back
-      def self.rollback(options : Hash(Symbol, DBAny))
+      def self.rollback(options : Hash(Symbol, DBAny), *, adapter : Adapter::Base = default_adapter)
         processed = true
-        default_adapter.ready_to_migrate!
+        adapter.ready_to_migrate!
         migrations = Base.migrations
         return if migrations.empty? || !Version.all.exists?
 
@@ -68,43 +68,36 @@ module Jennifer
           end
 
         versions.each do |version|
-          process_down_migration(migrations[version].new)
+          process_down_migration(migrations[version].new, adapter)
           processed = true
         end
       ensure
-        default_adapter.generate_schema if processed && !Config.skip_dumping_schema_sql
+        adapter.generate_schema if processed && !adapter.config.skip_dumping_schema_sql
       end
 
       # Loads schema from the SQL schema file.
-      def self.load_schema
-        return if Config.skip_dumping_schema_sql
+      def self.load_schema(adapter : Adapter::Base = default_adapter)
+        return if adapter.config.skip_dumping_schema_sql
 
-        default_adapter.load_schema
+        adapter.load_schema
         puts "Schema loaded"
       end
 
-      # Returns whether pending migration exists.
-      #
-      # Pending migration - known Jennifer::Migration::Base subclasses that hasn't been run.
-      def self.pending_migration?
-        !pending_versions.empty?
-      end
-
       private def self.default_adapter
         Adapter.default_adapter
       end
 
       # NOTE: pending versions are memorized so reloading should be performed manually.
-      private def self.pending_versions
-        @@pending_versions = (Base.versions - Version.list).sort! if @@pending_versions.empty?
-        @@pending_versions
+      private def self.get_pending_versions
+        pending_versions = (Base.versions - Version.list).sort!
+        pending_versions
       end
 
       private def self.default_adapter_class
         Adapter.default_adapter_class
       end
 
-      private def self.process_up_migration(migration)
+      private def self.process_up_migration(migration, adapter)
         optional_transaction(migration) do
           process_with_announcement(migration, :up) do
             migration.up
@@ -113,17 +106,17 @@ module Jennifer
         end
       rescue e
         optional_transaction(migration) do
-          if Config.instance.migration_failure_handler_method.reverse_direction?
+          if adapter.config.migration_failure_handler_method.reverse_direction?
             migration.down
-          elsif Config.instance.migration_failure_handler_method.callback?
+          elsif adapter.config.migration_failure_handler_method.callback?
             migration.after_up_failure
           end
         end
 
         raise e
       end
 
-      private def self.process_down_migration(migration)
+      private def self.process_down_migration(migration, adapter)
         optional_transaction(migration) do
           process_with_announcement(migration, :down) do
             migration.down
@@ -132,9 +125,9 @@ module Jennifer
         end
       rescue e
         optional_transaction(migration) do
-          if Config.instance.migration_failure_handler_method.reverse_direction?
+          if adapter.config.migration_failure_handler_method.reverse_direction?
             migration.up
-          elsif Config.instance.migration_failure_handler_method.callback?
+          elsif adapter.config.migration_failure_handler_method.callback?
             migration.after_down_failure
           end
         end
@@ -156,7 +149,7 @@ module Jennifer
         puts "#{header} #{words[:end]} (#{time.milliseconds} ms)\n" if Config.config.verbose_migrations
       end
 
-      private def self.assert_outdated_pending_migrations
+      private def self.assert_outdated_pending_migrations(pending_versions)
         return if !Version.all.exists? || Config.config.allow_outdated_pending_migration
 
         db_version = Version.all.order(version: :desc).limit(1).pluck(:version)[0].as(String)

src/jennifer/migration/version.cr

@@ -9,6 +9,17 @@ module Jennifer
         version: String
       )
 
+      @@adapter : Adapter::Base?
+
+      def self.adapter
+        @@adapter.not_nil!
+      end
+
+      def self.adapter=(adapter : Adapter::Base)
+        @@adapter = adapter
+        adapter
+      end
+
       def self.has_table?
         false
       end