Initial mr template API setup

Add endpoint to get desired payload
Add namespace and project props

app/assets/javascripts/api.js

@@ -34,6 +34,7 @@ const Api = {
   mergeRequestsPath: '/api/:version/merge_requests',
   groupLabelsPath: '/groups/:namespace_path/-/labels',
   issuableTemplatePath: '/:namespace_path/:project_path/templates/:type/:key',
+  issuableTemplatesPath: '/:namespace_path/:project_path/templates/:type',
   projectTemplatePath: '/api/:version/projects/:id/templates/:type/:key',
   projectTemplatesPath: '/api/:version/projects/:id/templates/:type',
   userCountsPath: '/api/:version/user_counts',
@@ -471,6 +472,17 @@ const Api = {
       .catch(callback);
   },
 
+  issueTemplates(namespacePath, projectPath, type, callback) {
+    const url = Api.buildUrl(Api.issuableTemplatesPath)
+      .replace(':type', type)
+      .replace(':project_path', projectPath)
+      .replace(':namespace_path', namespacePath);
+    return axios
+      .get(url)
+      .then(({ data }) => callback(null, data))
+      .catch(callback);
+  },
+
   users(query, options) {
     const url = Api.buildUrl(this.usersPath);
     return axios.get(url, {

app/assets/javascripts/static_site_editor/components/edit_meta_modal.vue

 <script>
 import { GlModal } from '@gitlab/ui';
 import { __, s__, sprintf } from '~/locale';
+import Api from '~/api';
 import LocalStorageSync from '~/vue_shared/components/local_storage_sync.vue';
 
 import EditMetaControls from './edit_meta_controls.vue';
@@ -18,6 +19,14 @@ export default {
       type: String,
       required: true,
     },
+    namespace: {
+      type: String,
+      required: true,
+    },
+    project: {
+      type: String,
+      required: true,
+    },
   },
   data() {
     return {
@@ -49,10 +58,19 @@ export default {
       };
     },
   },
+  mounted() {
+    this.initTemplates();
+  },
   methods: {
     hide() {
       this.$refs.modal.hide();
     },
+    initTemplates() {
+      Api.issueTemplates(this.namespace, this.project, 'merge_request', (err, templates) => {
+        if (err) return; // Error handled by global AJAX error handler
+        this.mergeRequestTemplates = templates;
+      });
+    },
     show() {
       this.$refs.modal.show();
     },

app/assets/javascripts/static_site_editor/pages/home.vue

@@ -148,6 +148,8 @@ export default {
       <edit-meta-modal
         ref="editMetaModal"
         :source-path="appData.sourcePath"
+        :namespace="appData.project.split('/')[0]"
+        :project="appData.project.split('/')[1]"
         @primary="onSubmit"
         @hide="onHideModal"
       />

app/controllers/projects/templates_controller.rb

@@ -7,6 +7,14 @@ class Projects::TemplatesController < Projects::ApplicationController
 
   feature_category :templates
 
+  def index
+    templates = @template_type.template_subsets(project)
+
+    respond_to do |format|
+      format.json { render json: templates.to_json }
+    end
+  end
+
   def show
     template = @template_type.find(params[:key], project)
 

config/routes/project.rb

@@ -403,6 +403,11 @@ constraints(::Constraints::ProjectUrlConstrainer.new) do
       #
       # Templates
       #
+      get '/templates/:template_type' => 'templates#index', # rubocop:todo Cop/PutProjectRoutesUnderScope
+          as: :templates,
+          defaults: { format: 'json' },
+          constraints: { template_type: %r{issue|merge_request}, format: 'json' }
+
       get '/templates/:template_type/:key' => 'templates#show', # rubocop:todo Cop/PutProjectRoutesUnderScope
           as: :template,
           defaults: { format: 'json' },

lib/gitlab/template/base_template.rb

@@ -105,6 +105,20 @@ module Gitlab
             files.map { |t| { name: t.name } }
           end
         end
+
+        def template_subsets(project = nil)
+          return [] if project && !project.repository.exists?
+
+          if categories.any?
+            categories.keys.map do |category|
+              files = self.by_category(category, project)
+              [category, files.map { |t| { key: t.key, name: t.name, content: t.content} }]
+            end.to_h
+          else
+            files = self.all(project)
+            files.map { |t| { key: t.key, name: t.name, content: t.content} }
+          end
+        end
       end
     end
   end