Project serve based on lang (#160)

# What's Changed?

- Added ability to specify preferred locale(s) in the REST API
request/GraphQL query that will determine the version of the project
loaded
- Created `ProjectLoader` to choose which version of the project to load
based on preferred locales
- Refactored GraphQL `project` query and `ProjectsController#show` to
use the `ProjectLoader`

closes #146

---------

Co-authored-by: loiswells97 <[email protected]>
Co-authored-by: Lois Wells <[email protected]>
Co-authored-by: Lois Wells <[email protected]>

Author: create-issue-branch[bot]

app/controllers/api/projects_controller.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require 'project_loader'
+
 module Api
   class ProjectsController < ApiController
     before_action :authorize_user, only: %i[create update index destroy]
@@ -49,7 +51,8 @@ def destroy
     private
 
     def load_project
-      @project = Project.find_by!(identifier: params[:id])
+      project_loader = ProjectLoader.new(params[:id], [params[:locale]])
+      @project = project_loader.load
     end
 
     def load_projects

app/graphql/types/query_type.rb

@@ -11,14 +11,17 @@ class QueryType < Types::BaseObject
 
     field :project, Types::ProjectType, 'Find a project by identifier' do
       argument :identifier, String, required: true, description: 'Project identifier'
+      argument :preferred_locales, [String], required: false,
+                                             description: 'List of preferred project locales, defaults to ["en"]'
     end
 
     field :projects, Types::ProjectType.connection_type, 'All viewable projects' do
       argument :user_id, String, required: false, description: 'Filter by user ID'
     end
 
-    def project(identifier:)
-      Project.find_by(identifier:)
+    def project(identifier:, preferred_locales: ['en'])
+      project_loader = ProjectLoader.new(identifier, preferred_locales)
+      project_loader.load
     end
 
     def projects(user_id: nil)

db/schema.graphql

@@ -549,6 +549,11 @@ type Query {
     Project identifier
     """
     identifier: String!
+
+    """
+    List of preferred project locales, defaults to ["en"]
+    """
+    preferredLocales: [String!]
   ): Project
 
   """

lib/project_loader.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+class ProjectLoader
+  attr_reader :identifier, :locale
+
+  def initialize(identifier, locales)
+    @identifier = identifier
+    @locales = [*locales, 'en', nil]
+  end
+
+  def load
+    projects = Project.where(identifier:, locale: @locales)
+    projects.min_by { |project| @locales.find_index(project.locale) }
+  end
+end

spec/graphql/queries/project_query_spec.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 require 'rails_helper'
+require 'project_loader'
 
 RSpec.describe 'query { project { ... } }' do
   subject(:result) { execute_query(query:, variables:) }
@@ -13,13 +14,20 @@
     it { expect(query).not_to be_a_valid_graphql_query }
   end
 
-  context 'with an identifier' do
-    let(:query) { 'query ($identifier: String!) { project(identifier: $identifier) { id } }' }
+  context 'with an identifier and locales' do
+    let(:query) { 'query ($identifier: String!, $preferred_locales: [String!]) { project(identifier: $identifier, preferredLocales: $preferred_locales) { id } }' }
     let(:project) { create(:project, user_id: nil) }
-    let(:variables) { { identifier: project.identifier } }
+    let(:variables) { { identifier: project.identifier, preferred_locales: [project.locale, 'another_locale'] } }
 
     it { expect(query).to be_a_valid_graphql_query }
 
+    it 'instantiates ProjectLoader with correct arguments' do
+      allow(ProjectLoader).to receive(:new).and_call_original
+      result
+      expect(ProjectLoader).to have_received(:new)
+        .with(project.identifier, [project.locale, 'another_locale'])
+    end
+
     it 'returns the project global id' do
       expect(result.dig('data', 'project', 'id')).to eq project.to_gid_param
     end
@@ -41,7 +49,7 @@
     end
 
     context 'when introspecting project components' do
-      let(:query) { 'query ($identifier: String!) { project(identifier: $identifier) { components { __typename } } }' }
+      let(:query) { 'query ($identifier: String!, $preferred_locales: [String!]) { project(identifier: $identifier, preferredLocales: $preferred_locales) { components { __typename } } }' }
 
       it { expect(query).to be_a_valid_graphql_query }
 
@@ -51,7 +59,7 @@
     end
 
     context 'when introspecting project images' do
-      let(:query) { 'query ($identifier: String!) { project(identifier: $identifier) { images { __typename } } }' }
+      let(:query) { 'query ($identifier: String!, $preferred_locales: [String!]) { project(identifier: $identifier, preferredLocales: $preferred_locales) { images { __typename } } }' }
 
       it { expect(query).to be_a_valid_graphql_query }
 
@@ -61,7 +69,7 @@
     end
 
     context 'when introspecting a remixed project parent' do
-      let(:query) { 'query ($identifier: String!) { project(identifier: $identifier) { remixedFrom { __typename } } }' }
+      let(:query) { 'query ($identifier: String!, $preferred_locales: [String!]) { project(identifier: $identifier, preferredLocales: $preferred_locales) { remixedFrom { __typename } } }' }
       let(:project) { create(:project, user_id: nil, parent: create(:project, user_id: nil)) }
 
       it { expect(query).to be_a_valid_graphql_query }

spec/project_importer_spec.rb renamed to spec/lib/project_importer_spec.rb

@@ -0,0 +1,57 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+require 'project_loader'
+
+RSpec.describe ProjectLoader do
+  let(:identifier) { PhraseIdentifier.generate }
+  let(:preferred_locales) { %w[locale1 locale2] }
+  let(:loaded_project) do
+    described_class.new(
+      identifier,
+      preferred_locales
+    ).load
+  end
+
+  context 'when projects exist in both preferred locales' do
+    let!(:preferred_project) { create(:project, identifier:, locale: 'locale1', user_id: nil) }
+
+    before do
+      create(:project, identifier:, locale: 'locale2', user_id: nil)
+    end
+
+    it 'returns the project with the locale highest on list' do
+      expect(loaded_project).to eq(preferred_project)
+    end
+  end
+
+  context 'when project exists in second locale but not first' do
+    let!(:preferred_project) { create(:project, identifier:, locale: 'locale2', user_id: nil) }
+
+    it 'returns the project with the locale highest on list' do
+      expect(loaded_project).to eq(preferred_project)
+    end
+  end
+
+  context 'when English project with identifier exists' do
+    let!(:english_project) { create(:project, identifier:, locale: 'en') }
+
+    it 'defaults to en' do
+      expect(loaded_project).to eq(english_project)
+    end
+  end
+
+  context 'when no preferred locale or English versions but user version exists' do
+    let!(:user_project) { create(:project, identifier:, locale: nil) }
+
+    it 'loads user project' do
+      expect(loaded_project).to eq(user_project)
+    end
+  end
+
+  context 'when no project with identifier' do
+    it 'returns nil' do
+      expect(loaded_project).to be_nil
+    end
+  end
+end

spec/lib/project_loader_spec.rb

@@ -6,7 +6,7 @@
   let(:user_id) { 'e0675b6c-dc48-4cd6-8c04-0f7ac05af51a' }
 
   context 'when user is logged in' do
-    let!(:project) { create(:project, user_id:) }
+    let!(:project) { create(:project, user_id:, locale: nil) }
     let(:headers) { { Authorization: 'dummy-token' } }
 
     before do
@@ -28,7 +28,7 @@
     end
 
     context 'when attempting to delete another users project' do
-      let(:non_owned_project) { create(:project) }
+      let(:non_owned_project) { create(:project, locale: nil) }
 
       it 'returns forbidden' do
         delete("/api/projects/#{non_owned_project.identifier}", headers:)

spec/requests/projects/destroy_spec.rb

@@ -3,7 +3,7 @@
 require 'rails_helper'
 
 RSpec.describe 'Project show requests' do
-  let!(:project) { create(:project) }
+  let!(:project) { create(:project, locale: nil) }
   let(:project_json) do
     {
       identifier: project.identifier,
@@ -43,12 +43,13 @@
     end
 
     context 'when loading another user\'s project' do
-      let!(:another_project) { create(:project) }
+      let!(:another_project) { create(:project, locale: nil) }
       let(:another_project_json) do
         {
           identifier: another_project.identifier,
           project_type: 'python',
           name: another_project.name,
+          locale: another_project.locale,
           user_id: another_project.user_id,
           components: [],
           image_list: []
@@ -70,7 +71,7 @@
 
   context 'when user is not logged in' do
     context 'when loading a starter project' do
-      let!(:starter_project) { create(:project, user_id: nil) }
+      let!(:starter_project) { create(:project, user_id: nil, locale: 'ja-JP') }
       let(:starter_project_json) do
         {
           identifier: starter_project.identifier,
@@ -84,25 +85,31 @@
       end
 
       it 'returns success response' do
-        get("/api/projects/#{starter_project.identifier}", headers:)
-
+        get("/api/projects/#{starter_project.identifier}?locale=#{starter_project.locale}", headers:)
         expect(response).to have_http_status(:ok)
       end
 
       it 'returns json' do
-        get("/api/projects/#{starter_project.identifier}", headers:)
+        get("/api/projects/#{starter_project.identifier}?locale=#{starter_project.locale}", headers:)
         expect(response.content_type).to eq('application/json; charset=utf-8')
       end
 
       it 'returns the project json' do
-        get("/api/projects/#{starter_project.identifier}", headers:)
+        get("/api/projects/#{starter_project.identifier}?locale=#{starter_project.locale}", headers:)
         expect(response.body).to eq(starter_project_json)
       end
 
       it 'returns 404 response if invalid project' do
         get('/api/projects/no-such-project', headers:)
         expect(response).to have_http_status(:not_found)
       end
+
+      it 'creates a new ProjectLoader with the correct parameters' do
+        allow(ProjectLoader).to receive(:new).and_call_original
+        get("/api/projects/#{starter_project.identifier}?locale=#{starter_project.locale}", headers:)
+        expect(ProjectLoader).to have_received(:new)
+          .with(starter_project.identifier, [starter_project.locale])
+      end
     end
 
     context 'when loading an owned project' do

spec/requests/projects/show_spec.rb

@@ -5,10 +5,10 @@
 RSpec.describe 'Project update requests' do
   let(:headers) { { Authorization: 'dummy-token' } }
   let(:user_id) { 'e0675b6c-dc48-4cd6-8c04-0f7ac05af51a' }
-  let(:project) { create(:project, user_id:) }
+  let(:project) { create(:project, user_id:, locale: nil) }
 
   context 'when authed user is project creator' do
-    let(:project) { create(:project, :with_default_component) }
+    let(:project) { create(:project, :with_default_component, locale: nil) }
     let!(:component) { create(:component, project:) }
     let(:default_component_params) do
       project.components.first.attributes.symbolize_keys.slice(
@@ -79,7 +79,7 @@
   end
 
   context 'when authed user is not creator' do
-    let(:project) { create(:project) }
+    let(:project) { create(:project, locale: nil) }
     let(:params) { { project: { components: [] } } }
 
     before do