Merge pull request #203 from iknow/migration-controller-concern

Extract migration parsing to a controller concern

lib/iknow_view_models/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module IknowViewModels
-  VERSION = '3.9.2'
+  VERSION = '3.10.0'
 end

lib/view_model/active_record/controller.rb

@@ -3,6 +3,7 @@
 require 'view_model/active_record/controller_base'
 require 'view_model/active_record/collection_nested_controller'
 require 'view_model/active_record/singular_nested_controller'
+require 'view_model/controller/migration_versions'
 
 # Controller for accessing an ViewModel::ActiveRecord
 # Provides for the following routes:
@@ -16,8 +17,7 @@ module ViewModel::ActiveRecord::Controller
   include ViewModel::ActiveRecord::ControllerBase
   include ViewModel::ActiveRecord::CollectionNestedController
   include ViewModel::ActiveRecord::SingularNestedController
-
-  MIGRATION_VERSION_HEADER = 'X-ViewModel-Versions'
+  include ViewModel::Controller::MigrationVersions
 
   def show(scope: nil, viewmodel_class: self.viewmodel_class, serialize_context: new_serialize_context(viewmodel_class: viewmodel_class))
     view = nil
@@ -95,51 +95,6 @@ def viewmodel_id
     parse_param(:id)
   end
 
-  def migration_versions
-    @migration_versions ||=
-      begin
-        specified_migration_versions.reject do |viewmodel_class, required_version|
-          viewmodel_class.schema_version == required_version
-        end.freeze
-      end
-  end
-
-  def specified_migration_versions
-    @specified_migration_versions ||=
-      begin
-        version_spec =
-          if params.include?(:versions)
-            params[:versions]
-          elsif request.headers.include?(MIGRATION_VERSION_HEADER)
-            begin
-              JSON.parse(request.headers[MIGRATION_VERSION_HEADER])
-            rescue JSON::ParserError
-              raise ViewModel::Error.new(status: 400, detail: "Invalid JSON in #{MIGRATION_VERSION_HEADER}")
-            end
-          else
-            {}
-          end
-
-        versions =
-          IknowParams::Parser.parse_value(
-            version_spec,
-            with: IknowParams::Serializer::HashOf.new(
-              IknowParams::Serializer::String, IknowParams::Serializer::Integer))
-
-        migration_versions = {}
-
-        versions.each do |view_name, required_version|
-          viewmodel_class = ViewModel::Registry.for_view_name(view_name)
-          migration_versions[viewmodel_class] = required_version
-        rescue ViewModel::DeserializationError::UnknownView
-          # Ignore requests to migrate types that no longer exist
-          next
-        end
-
-        migration_versions.freeze
-      end
-  end
-
   def migrated_deep_schema_version
     ViewModel::Migrator.migrated_deep_schema_version(viewmodel_class, migration_versions, include_referenced: true)
   end

lib/view_model/controller/migration_versions.rb

@@ -0,0 +1,52 @@
+# frozen_string_literal: true
+
+module ViewModel::Controller::MigrationVersions
+  extend ActiveSupport::Concern
+
+  MIGRATION_VERSION_HEADER = 'X-ViewModel-Versions'
+
+  def migration_versions
+    @migration_versions ||=
+      begin
+        specified_migration_versions.reject do |viewmodel_class, required_version|
+          viewmodel_class.schema_version == required_version
+        end.freeze
+      end
+  end
+
+  def specified_migration_versions
+    @specified_migration_versions ||=
+      begin
+        version_spec =
+          if params.include?(:versions)
+            params[:versions]
+          elsif request.headers.include?(MIGRATION_VERSION_HEADER)
+            begin
+              JSON.parse(request.headers[MIGRATION_VERSION_HEADER])
+            rescue JSON::ParserError
+              raise ViewModel::Error.new(status: 400, detail: "Invalid JSON in #{MIGRATION_VERSION_HEADER}")
+            end
+          else
+            {}
+          end
+
+        versions =
+          IknowParams::Parser.parse_value(
+            version_spec,
+            with: IknowParams::Serializer::HashOf.new(
+              IknowParams::Serializer::String, IknowParams::Serializer::Integer))
+
+        migration_versions = {}
+
+        versions.each do |view_name, required_version|
+          viewmodel_class = ViewModel::Registry.for_view_name(view_name)
+          migration_versions[viewmodel_class] = required_version
+        rescue ViewModel::DeserializationError::UnknownView
+          # Ignore requests to migrate types that no longer exist
+          next
+        end
+
+        migration_versions.freeze
+      end
+  end
+end