Changed autocomplete_sources into an action that returns a single 'at' type of sources at a time

Finished up autocomplete_sources action and added frontend to fetch data only when its needed

Added wait_for_ajax to specs

Fixed builds and improved the setup/destroy lifecycle

Changed global namespace and DRYed up loading logic

Added safety for accidentally loading data twice

Removed destroy as its not necessary and is messing with click events from a blur race condition

Created AutocompleteSourcesController and updated routes

Fixed @undefined from tabbing before load ends

Disable tabSelectsMatch until we have loaded data

Review changes

app/assets/javascripts/gl_form.js

@@ -30,7 +30,7 @@
         this.form.addClass('gfm-form');
         // remove notify commit author checkbox for non-commit notes
         gl.utils.disableButtonIfEmptyField(this.form.find('.js-note-text'), this.form.find('.js-comment-button'));
-        GitLab.GfmAutoComplete.setup(this.form.find('.js-gfm-input'));
+        gl.GfmAutoComplete.setup(this.form.find('.js-gfm-input'));
         new DropzoneInput(this.form);
         autosize(this.textarea);
         // form and textarea event listeners

app/assets/javascripts/issuable_form.js

@@ -19,7 +19,7 @@
       this.renderWipExplanation = bind(this.renderWipExplanation, this);
       this.resetAutosave = bind(this.resetAutosave, this);
       this.handleSubmit = bind(this.handleSubmit, this);
-      GitLab.GfmAutoComplete.setup();
+      gl.GfmAutoComplete.setup();
       new UsersSelect();
       new ZenMode();
       this.titleField = this.form.find("input[name*='[title]']");

app/controllers/projects/autocomplete_sources_controller.rb

+class Projects::AutocompleteSourcesController < Projects::ApplicationController
+  before_action :load_autocomplete_service, except: [:emojis, :members]
+
+  def emojis
+    render json: Gitlab::AwardEmoji.urls
+  end
+
+  def members
+    render json: ::Projects::ParticipantsService.new(@project, current_user).execute(noteable)
+  end
+
+  def issues
+    render json: @autocomplete_service.issues
+  end
+
+  def merge_requests
+    render json: @autocomplete_service.merge_requests
+  end
+
+  def labels
+    render json: @autocomplete_service.labels
+  end
+
+  def milestones
+    render json: @autocomplete_service.milestones
+  end
+
+  def commands
+    render json: @autocomplete_service.commands(noteable, params[:type])
+  end
+
+  private
+
+  def load_autocomplete_service
+    @autocomplete_service = ::Projects::AutocompleteService.new(@project, current_user)
+  end
+
+  def noteable
+    case params[:type]
+    when 'Issue'
+      IssuesFinder.new(current_user, project_id: @project.id).execute.find_by(iid: params[:type_id])
+    when 'MergeRequest'
+      MergeRequestsFinder.new(current_user, project_id: @project.id).execute.find_by(iid: params[:type_id])
+    when 'Commit'
+      @project.commit(params[:type_id])
+    end
+  end
+end

app/controllers/projects_controller.rb

@@ -127,39 +127,6 @@ class ProjectsController < Projects::ApplicationController
     redirect_to edit_project_path(@project), alert: ex.message
   end
 
-  def autocomplete_sources
-    noteable =
-      case params[:type]
-      when 'Issue'
-        IssuesFinder.new(current_user, project_id: @project.id).
-          execute.find_by(iid: params[:type_id])
-      when 'MergeRequest'
-        MergeRequestsFinder.new(current_user, project_id: @project.id).
-          execute.find_by(iid: params[:type_id])
-      when 'Commit'
-        @project.commit(params[:type_id])
-      else
-        nil
-      end
-
-    autocomplete = ::Projects::AutocompleteService.new(@project, current_user)
-    participants = ::Projects::ParticipantsService.new(@project, current_user).execute(noteable)
-
-    @suggestions = {
-      emojis: Gitlab::AwardEmoji.urls,
-      issues: autocomplete.issues,
-      milestones: autocomplete.milestones,
-      mergerequests: autocomplete.merge_requests,
-      labels: autocomplete.labels,
-      members: participants,
-      commands: autocomplete.commands(noteable, params[:type])
-    }
-
-    respond_to do |format|
-      format.json { render json: @suggestions }
-    end
-  end
-
   def new_issue_address
     return render_404 unless Gitlab::IncomingEmail.supports_issue_creation?
 

app/views/layouts/_init_auto_complete.html.haml

@@ -3,6 +3,14 @@
 
 - if project
   :javascript
-    GitLab.GfmAutoComplete.dataSource = "#{autocomplete_sources_namespace_project_path(project.namespace, project, type: noteable_type, type_id: params[:id])}"
-    GitLab.GfmAutoComplete.cachedData = undefined;
-    GitLab.GfmAutoComplete.setup();
+    gl.GfmAutoComplete.dataSources = {
+      emojis: "#{emojis_namespace_project_autocomplete_sources_path(project.namespace, project)}",
+      members: "#{members_namespace_project_autocomplete_sources_path(project.namespace, project, type: noteable_type, type_id: params[:id])}",
+      issues: "#{issues_namespace_project_autocomplete_sources_path(project.namespace, project)}",
+      mergeRequests: "#{merge_requests_namespace_project_autocomplete_sources_path(project.namespace, project)}",
+      labels: "#{labels_namespace_project_autocomplete_sources_path(project.namespace, project)}",
+      milestones: "#{milestones_namespace_project_autocomplete_sources_path(project.namespace, project)}",
+      commands: "#{commands_namespace_project_autocomplete_sources_path(project.namespace, project, type: noteable_type, type_id: params[:id])}"
+    };
+
+    gl.GfmAutoComplete.setup();

changelogs/unreleased/18435-autocomplete-is-not-performant.yml

+---
+title: Made comment autocomplete more performant and removed some loading bugs
+merge_request: 6856
+author: 

config/routes/project.rb

@@ -11,6 +11,18 @@ constraints(ProjectUrlConstrainer.new) do
           module: :projects,
           as: :project) do
 
+      resources :autocomplete_sources, only: [] do
+        collection do
+          get 'emojis'
+          get 'members'
+          get 'issues'
+          get 'merge_requests'
+          get 'labels'
+          get 'milestones'
+          get 'commands'
+        end
+      end
+
       #
       # Templates
       #
@@ -316,7 +328,6 @@ constraints(ProjectUrlConstrainer.new) do
         post :remove_export
         post :generate_new_export
         get :download_export
-        get :autocomplete_sources
         get :activity
         get :refs
         put :new_issue_address

spec/features/participants_autocomplete_spec.rb

 require 'spec_helper'
 
 feature 'Member autocomplete', feature: true do
+  include WaitForAjax
+
   let(:project) { create(:project, :public) }
   let(:user) { create(:user) }
   let(:participant) { create(:user) }
@@ -79,11 +81,10 @@ feature 'Member autocomplete', feature: true do
   end
 
   def open_member_suggestions
-    sleep 1
     page.within('.new-note') do
-      sleep 1
-      find('#note_note').native.send_keys('@')
+      find('#note_note').send_keys('@')
     end
+    wait_for_ajax
   end
 
   def visit_issue(project, issue)

spec/features/projects/gfm_autocomplete_load_spec.rb

@@ -10,12 +10,12 @@ describe 'GFM autocomplete loading', feature: true, js: true do
   end
 
   it 'does not load on project#show' do
-    expect(evaluate_script('GitLab.GfmAutoComplete.dataSource')).to eq('')
+    expect(evaluate_script('gl.GfmAutoComplete.dataSources')).to eq({})
   end
 
   it 'loads on new issue page' do
     visit new_namespace_project_issue_path(project.namespace, project)
 
-    expect(evaluate_script('GitLab.GfmAutoComplete.dataSource')).not_to eq('')
+    expect(evaluate_script('gl.GfmAutoComplete.dataSources')).not_to eq({})
   end
 end

spec/routing/project_routing_spec.rb

@@ -80,10 +80,6 @@ describe 'project routing' do
       expect(get('/gitlab/gitlabhq/edit')).to route_to('projects#edit', namespace_id: 'gitlab', id: 'gitlabhq')
     end
 
-    it 'to #autocomplete_sources' do
-      expect(get('/gitlab/gitlabhq/autocomplete_sources')).to route_to('projects#autocomplete_sources', namespace_id: 'gitlab', id: 'gitlabhq')
-    end
-
     describe 'to #show' do
       context 'regular name' do
         it { expect(get('/gitlab/gitlabhq')).to route_to('projects#show', namespace_id: 'gitlab', id: 'gitlabhq') }
@@ -117,6 +113,21 @@ describe 'project routing' do
     end
   end
 
+  # emojis_namespace_project_autocomplete_sources_path         GET /:project_id/autocomplete_sources/emojis(.:format)         projects/autocomplete_sources#emojis
+  # members_namespace_project_autocomplete_sources_path        GET /:project_id/autocomplete_sources/members(.:format)        projects/autocomplete_sources#members
+  # issues_namespace_project_autocomplete_sources_path         GET /:project_id/autocomplete_sources/issues(.:format)         projects/autocomplete_sources#issues
+  # merge_requests_namespace_project_autocomplete_sources_path GET /:project_id/autocomplete_sources/merge_requests(.:format) projects/autocomplete_sources#merge_requests
+  # labels_namespace_project_autocomplete_sources_path         GET /:project_id/autocomplete_sources/labels(.:format)         projects/autocomplete_sources#labels
+  # milestones_namespace_project_autocomplete_sources_path     GET /:project_id/autocomplete_sources/milestones(.:format)     projects/autocomplete_sources#milestones
+  # commands_namespace_project_autocomplete_sources_path       GET /:project_id/autocomplete_sources/commands(.:format)       projects/autocomplete_sources#commands
+  describe Projects::AutocompleteSourcesController, 'routing' do
+    [:emojis, :members, :issues, :merge_requests, :labels, :milestones, :commands].each do |action|
+      it "to ##{action}" do
+        expect(get("/gitlab/gitlabhq/autocomplete_sources/#{action}")).to route_to("projects/autocomplete_sources##{action}", namespace_id: 'gitlab', project_id: 'gitlabhq')
+      end
+    end
+  end
+
   #  pages_project_wikis GET    /:project_id/wikis/pages(.:format)       projects/wikis#pages
   # history_project_wiki GET    /:project_id/wikis/:id/history(.:format) projects/wikis#history
   #        project_wikis POST   /:project_id/wikis(.:format)             projects/wikis#create