Merge branch 'gokmengoksel/gitlab-ce-koding' into 'master'

Koding Integration

## What does this MR do?

Will provide Koding integration with GitLab services. Forked from !4914.

## Are there points in the code the reviewer needs to double check?
I've introduced new layouts which might not be necessary, first time contributor. 

## Why was this MR needed?
We're planning to ship Koding with GitLab.

## What are the relevant issue numbers?
#12759 #14698 

## Screenshots (if relevant)

### Screencasts

http://recordit.co/BDMbhwgxPD
http://recordit.co/By0qiz1ClC

### Enable Koding in Application Settings

![image](/uploads/73a69421105c03aa2b0b47e2617d3fbc/image.png)

### Koding Dashboard
![image](/uploads/6c7dda34792280c0e4791e36af4eba11/image.png)

### Set up Koding Stack
1 - ![image](/uploads/d5c2b93f8e61b5cbffdb06f0267d485f/image.png)
2 - ![image](/uploads/44d9a9b574b8ac0c5eb553fb9653d5da/image.png)

### Run on Koding on Project Page

![image](/uploads/7d2b46221009074ffff75d66d5a1a555/image.png)

### Run in IDE on Merge Requests
![image](/uploads/65eed90c34c34b5fe7ad29ef9c717640/image.png)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5909

CHANGELOG

@@ -4,6 +4,7 @@ v 8.11.0 (unreleased)
   - Use test coverage value from the latest successful pipeline in badge. !5862
   - Add test coverage report badge. !5708
   - Remove the http_parser.rb dependency by removing the tinder gem. !5758 (tbalthazar)
+  - Add Koding (online IDE) integration
   - Ability to specify branches for Pivotal Tracker integration (Egor Lynko)
   - Fix don't pass a local variable called `i` to a partial. !20510 (herminiotorres)
   - Add delimiter to project stars and forks count (ClemMakesApps)

app/assets/images/koding-logo.svg

+<?xml version="1.0" encoding="utf-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 12 14">
+    <g fill="#d6d7d9">
+        <path d="M8.7 0L5.3.3l3.2 6.8-3.2 6.6 3.5.3L12 6.9z"/>
+        <ellipse cx="1.7" cy="11.1" rx="1.7" ry="1.7"/>
+        <ellipse cx="1.7" cy="5.6" rx="1.7" ry="1.7"/>
+    </g>
+</svg>
\ No newline at end of file

app/controllers/admin/application_settings_controller.rb

@@ -109,6 +109,8 @@ class Admin::ApplicationSettingsController < Admin::ApplicationController
       :sentry_dsn,
       :akismet_enabled,
       :akismet_api_key,
+      :koding_enabled,
+      :koding_url,
       :email_author_in_body,
       :repository_checks_enabled,
       :metrics_packet_size,

app/controllers/koding_controller.rb

+class KodingController < ApplicationController
+  before_action :check_integration!, :authenticate_user!, :reject_blocked!
+  layout 'koding'
+
+  def index
+    path = File.join(Rails.root, 'doc/integration/koding-usage.md')
+    @markdown = File.read(path)
+  end
+
+  private
+
+  def check_integration!
+    render_404 unless current_application_settings.koding_enabled?
+  end
+end

app/helpers/application_settings_helper.rb

@@ -31,6 +31,10 @@ module ApplicationSettingsHelper
     current_application_settings.akismet_enabled?
   end
 
+  def koding_enabled?
+    current_application_settings.koding_enabled?
+  end
+
   def allowed_protocols_present?
     current_application_settings.enabled_git_access_protocol.present?
   end

app/helpers/projects_helper.rb

@@ -236,6 +236,60 @@ module ProjectsHelper
     )
   end
 
+  def add_koding_stack_path(project)
+    namespace_project_new_blob_path(
+      project.namespace,
+      project,
+      project.default_branch || 'master',
+      file_name:      '.koding.yml',
+      commit_message: "Add Koding stack script",
+      content: <<-CONTENT.strip_heredoc
+        provider:
+          aws:
+            access_key: '${var.aws_access_key}'
+            secret_key: '${var.aws_secret_key}'
+        resource:
+          aws_instance:
+            #{project.path}-vm:
+              instance_type: t2.nano
+              user_data: |-
+
+                # Created by GitLab UI for :>
+
+                echo _KD_NOTIFY_@Installing Base packages...@
+
+                apt-get update -y
+                apt-get install git -y
+
+                echo _KD_NOTIFY_@Cloning #{project.name}...@
+
+                export KODING_USER=${var.koding_user_username}
+                export REPO_URL=#{root_url}${var.koding_queryString_repo}.git
+                export BRANCH=${var.koding_queryString_branch}
+
+                sudo -i -u $KODING_USER git clone $REPO_URL -b $BRANCH
+
+                echo _KD_NOTIFY_@#{project.name} cloned.@
+      CONTENT
+    )
+  end
+
+  def koding_project_url(project = nil, branch = nil, sha = nil)
+    if project
+      import_path = "/Home/Stacks/import"
+
+      repo = project.path_with_namespace
+      branch ||= project.default_branch
+      sha ||= project.commit.short_id
+
+      path = "#{import_path}?repo=#{repo}&branch=#{branch}&sha=#{sha}"
+
+      return URI.join(current_application_settings.koding_url, path).to_s
+    end
+
+    current_application_settings.koding_url
+  end
+
   def contribution_guide_path(project)
     if project && contribution_guide = project.repository.contribution_guide
       namespace_project_blob_path(

app/models/application_setting.rb

@@ -55,6 +55,10 @@ class ApplicationSetting < ActiveRecord::Base
             presence: true,
             if: :akismet_enabled
 
+  validates :koding_url,
+            presence: true,
+            if: :koding_enabled
+
   validates :max_attachment_size,
             presence: true,
             numericality: { only_integer: true, greater_than: 0 }
@@ -149,6 +153,8 @@ class ApplicationSetting < ActiveRecord::Base
       two_factor_grace_period: 48,
       recaptcha_enabled: false,
       akismet_enabled: false,
+      koding_enabled: false,
+      koding_url: nil,
       repository_checks_enabled: true,
       disabled_oauth_sign_in_sources: [],
       send_user_confirmation_email: false,

app/models/repository.rb

@@ -277,7 +277,7 @@ class Repository
   def cache_keys
     %i(size commit_count
        readme version contribution_guide changelog
-       license_blob license_key gitignore)
+       license_blob license_key gitignore koding_yml)
   end
 
   # Keys for data on branch/tag operations.
@@ -553,6 +553,14 @@ class Repository
     end
   end
 
+  def koding_yml
+    return nil unless head_exists?
+
+    cache.fetch(:koding_yml) do
+      file_on_head(/\A\.koding\.yml\z/)
+    end
+  end
+
   def gitlab_ci_yml
     return nil unless head_exists?
 

app/views/admin/application_settings/_form.html.haml

@@ -388,6 +388,25 @@
         .help-block
           If you got a lot of false alarms from repository checks you can choose to clear all repository check information from the database.
 
+  %fieldset
+    %legend Koding
+    .form-group
+      .col-sm-offset-2.col-sm-10
+        .checkbox
+          = f.label :koding_enabled do
+            = f.check_box :koding_enabled
+            Enable Koding
+    .form-group
+      = f.label :koding_url, 'Koding URL', class: 'control-label col-sm-2'
+      .col-sm-10
+        = f.text_field :koding_url, class: 'form-control', placeholder: 'http://gitlab.your-koding-instance.com:8090'
+        .help-block
+          Koding has integration enabled out of the box for the
+          %strong gitlab
+          team, and you need to provide that team's URL here. Learn more in the
+          = succeed "." do
+            = link_to "Koding integration documentation", help_page_path("integration/koding")
+
 
   .form-actions
     = f.submit 'Save', class: 'btn btn-save'

app/views/koding/index.html.haml

+.row-content-block.second-block.center
+  %p
+    = icon('circle', class: 'cgreen')
+    Integration is active for
+    = link_to koding_project_url, target: '_blank' do
+      #{current_application_settings.koding_url}
+
+.documentation.wiki
+  = markdown @markdown

app/views/layouts/koding.html.haml

+- page_title        "Koding"
+- page_description  "Koding Dashboard"
+- header_title      "Koding", koding_path
+
+= render template: "layouts/application"

app/views/layouts/nav/_dashboard.html.haml

@@ -12,6 +12,11 @@
     = link_to activity_dashboard_path, class: 'dashboard-shortcuts-activity', title: 'Activity' do
       %span
         Activity
+  - if koding_enabled?
+    = nav_link(controller: :koding) do
+      = link_to koding_path, title: 'Koding' do
+        %span
+          Koding
   = nav_link(controller: [:groups, 'groups/milestones', 'groups/group_members']) do
     = link_to dashboard_groups_path, title: 'Groups' do
       %span

app/views/projects/buttons/_koding.html.haml

+- if koding_enabled? && current_user && can_push_branch?(@project, @project.default_branch)
+  - if @repository.koding_yml
+    = link_to koding_project_url(@project), class: 'btn', target: '_blank' do
+      Run in IDE (Koding)
+  - else
+    = link_to add_koding_stack_path(@project), class: 'btn' do
+      Set Up Koding

app/views/projects/merge_requests/_show.html.haml

@@ -16,6 +16,9 @@
       - if @merge_request.open?
         .pull-right
           - if @merge_request.source_branch_exists?
+            - if koding_enabled? && @repository.koding_yml
+              = link_to koding_project_url(@merge_request.source_project, @merge_request.source_branch, @merge_request.commits.first.short_id), class: "btn inline btn-grouped btn-sm", target: '_blank' do
+                Run in IDE (Koding)
             = link_to "#modal_merge_info", class: "btn inline btn-grouped btn-sm", "data-toggle" => "modal" do
               Check out branch
 

app/views/projects/show.html.haml

@@ -64,10 +64,12 @@
         %li.missing
           = link_to add_special_file_path(@project, file_name: '.gitlab-ci.yml') do
             Set Up CI
+
     %li.project-repo-buttons-right
       .project-repo-buttons.project-right-buttons
         - if current_user
           = render 'shared/members/access_request_buttons', source: @project
+          = render "projects/buttons/koding"
 
         .btn-group.project-repo-btn-group
           = render "projects/buttons/download"
@@ -86,4 +88,4 @@
         Archived project! Repository is read-only
 
   %div{class: "project-show-#{default_project_view}"}
-    = render default_project_view
+    = render default_project_view
\ No newline at end of file

config/routes.rb

@@ -90,6 +90,11 @@ Rails.application.routes.draw do
   get 'help/ui'        => 'help#ui'
   get 'help/*path'     => 'help#show', as: :help_page
 
+  #
+  # Koding route
+  #
+  get 'koding' => 'koding#index'
+
   #
   # Global snippets
   #

db/migrate/20160817133006_add_koding_to_application_settings.rb

+class AddKodingToApplicationSettings < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  def change
+    add_column :application_settings, :koding_enabled, :boolean
+    add_column :application_settings, :koding_url, :string
+  end
+end

db/schema.rb

@@ -90,6 +90,8 @@ ActiveRecord::Schema.define(version: 20160818205718) do
     t.string   "enabled_git_access_protocol"
     t.boolean  "domain_blacklist_enabled",              default: false
     t.text     "domain_blacklist"
+    t.boolean  "koding_enabled"
+    t.string   "koding_url"
   end
 
   create_table "audit_events", force: :cascade do |t|

doc/integration/README.md

@@ -15,6 +15,7 @@ See the documentation below for details on how to configure these services.
 - [Gmail actions buttons](gmail_action_buttons_for_gitlab.md) Adds GitLab actions to messages
 - [reCAPTCHA](recaptcha.md) Configure GitLab to use Google reCAPTCHA for new users
 - [Akismet](akismet.md) Configure Akismet to stop spam
+- [Koding](koding.md) Configure Koding to use IDE integration
 
 GitLab Enterprise Edition contains [advanced Jenkins support][jenkins].
 

doc/integration/koding-usage.md

+# Koding & GitLab
+
+This document will guide you through using Koding integration on GitLab in
+detail. For configuring and installing please follow [this](koding.md) guide.
+
+You can use Koding integration to run and develop your projects on GitLab. This
+will allow you and the users to test your project without leaving the browser.
+Koding handles projects as stacks which are basic recipes to define your
+environment for your project. With this integration you can automatically
+create a proper stack template for your projects. Currently auto-generated
+stack templates are designed to work with AWS which requires a valid AWS
+credential to be able to use these stacks. You can find more information about
+stacks and the other providers that you can use on Koding from
+[here](https://www.koding.com/docs).
+
+
+# Enable Integration
+
+You can enable Koding integration by providing the running Koding instance URL
+in Application Settings;
+
+ - Open **Admin area > Settings** (`/admin/application_settings`).
+
+![Enable Koding](help/integration/img/koding_enable-koding.png)
+
+Once enabled you will see `Koding` link on your sidebar which leads you to
+Koding Landing page
+
+![Koding Landing](help/integration/img/koding_landing.png)
+
+You can navigate to running Koding instance from here. For more information and
+details about configuring integration please follow [this](koding.md) guide.
+
+
+# Set up Koding on Projects
+
+Once it's enabled, you will see some integration buttons on Project pages,
+Merge Requests etc. To get started working on a specific project you first need
+to create a `.koding.yml` file under your project root. You can easily do that
+by using `Set Up Koding` button which will be visible on every project's
+landing page;
+
+![Set Up Koding](help/integration/img/koding_set-up-ide.png)
+
+Once you click this will open a New File page on GitLab with auto-generated
+`.koding.yml` content based on your server and repository configuration.
+
+![Commit .koding.yml](help/integration/img/koding_commit-koding.yml.png)
+
+
+# Run a project on Koding
+
+If there is `.koding.yml` exists in your project root, you will see
+`Run in IDE (Koding)` button in your project landing page. You can initiate the
+process from here.
+
+![Run on Koding](help/integration/img/koding_run-in-ide.png)
+
+This will open Koding defined in the settings in a new window and will start
+importing the project's stack file;
+
+![Import Stack](help/integration/img/koding_stack-import.png)
+
+You should see the details of your repository imported into your Koding
+instance. Once it's completed it will lead you to the Stack Editor and from
+there you can start using your new stack integrated with your project on your
+GitLab instance. For details about what's next you can follow
+[this](https://www.koding.com/docs/creating-an-aws-stack) guide from 8. step.
+
+Once stack initialized you will see the `README.md` content from your project
+in `Stack Build` wizard, this wizard will let you to build the stack and import
+your project into it. **Once it's completed it will automatically open the
+related vm instead of importing from scratch**
+
+![Stack Building](help/integration/img/koding_start-build.png)
+
+This will take time depending on the required environment.
+
+![Stack Building in Progress](help/integration/img/koding_build-in-progress.png)
+
+It usually takes ~4 min. to make it ready with a `t2.nano` instance on given
+AWS region. (`t2.nano` is default vm type on auto-generated stack template
+which can be manually changed)
+
+![Stack Building Success](help/integration/img/koding_build-success.png)
+
+You can check out the `Build Logs` from this success modal as well;
+
+![Stack Build Logs](help/integration/img/koding_build-logs.png)
+
+You can now `Start Coding`!
+
+![Edit On IDE](help/integration/img/koding_edit-on-ide.png)
+
+
+# Try a Merge Request on IDE
+
+It's also possible to try a change on IDE before merging it. This flow only
+enabled if the target project has `.koding.yml` in it's target branch. You
+should see the alternative version of `Run in IDE (Koding)` button in merge
+request pages as well;
+
+![Run in IDE on MR](help/integration/img/koding_run-mr-in-ide.png)
+
+This will again take you to Koding with proper arguments passed, which will
+allow Koding to modify the stack template provided by target branch. You can
+see the difference;
+
+![Different Branch for MR](help/integration/img/koding_different-stack-on-mr-try.png)
+
+The flow for the branch stack is also same with the regular project flow.
+
+
+# Open GitLab from Koding
+
+Since stacks generated with import flow defined in previous steps, they have
+information about the repository they are belonging to. By using this
+information you can access to related GitLab page from stacks on your sidebar
+on Koding.
+
+![Open GitLab from Koding](help/integration/img/koding_open-gitlab-from-koding.png)
+

doc/integration/koding.md

+# Koding & GitLab
+
+This document will guide you through installing and configuring Koding with
+GitLab.
+
+First of all, to be able to use Koding and GitLab together you will need public
+access to your server. This allows you to use single sign-on from GitLab to
+Koding and using vms from cloud providers like AWS. Koding has a registry for
+VMs, called Kontrol and it runs on the same server as Koding itself, VMs from
+cloud providers register themselves to Kontrol via the agent that we put into
+provisioned VMs. This agent is called Klient and it provides Koding to access
+and manage the target machine.
+
+Kontrol and Klient are based on another technology called
+[Kite](github.com/koding/kite), that we have written at Koding. Which is a
+microservice framework that allows you to develop microservices easily.
+
+
+## Requirements
+
+### Hardware
+
+Minimum requirements are;
+
+  - 2 cores CPU
+  - 3G RAM
+  - 10G Storage
+
+If you plan to use AWS to install Koding it is recommended that you use at
+least a `c3.xlarge` instance.
+
+### Software
+
+  - [git](https://git-scm.com)
+  - [docker](https://www.docker.com)
+  - [docker-compose](https://www.docker.com/products/docker-compose)
+
+Koding can run on most of the UNIX based operating systems, since it's shipped
+as containerized with Docker support, it can work on any operating system that
+supports Docker.
+
+Required services are;
+
+  - PostgreSQL # Kontrol and Service DB provider
+  - MongoDB    # Main DB provider the application
+  - Redis      # In memory DB used by both application and services
+  - RabbitMQ   # Message Queue for both application and services
+
+which are also provided as a Docker container by Koding.
+
+
+## Getting Started with Development Versions
+
+
+### Koding
+
+You can run `docker-compose` environment for developing koding by
+executing commands in the following snippet.
+
+```bash
+git clone https://github.com/koding/koding.git
+cd koding
+docker-compose up
+```
+
+This should start koding on `localhost:8090`.
+
+By default there is no team exists in Koding DB. You'll need to create a team
+called `gitlab` which is the default team name for GitLab integration in the
+configuration. To make things in order it's recommended to create the `gitlab`
+team first thing after setting up Koding.
+
+
+### GitLab
+
+To install GitLab to your environment for development purposes it's recommended
+to use GitLab Development Kit which you can get it from
+[here](https://gitlab.com/gitlab-org/gitlab-development-kit).
+
+After all those steps, gitlab should be running on `localhost:3000`
+
+
+## Integration
+
+Integration includes following components;
+
+  - Single Sign On with OAuth from GitLab to Koding
+  - System Hook integration for handling GitLab events on Koding
+    (`project_created`, `user_joined` etc.)
+  - Service endpoints for importing/executing stacks from GitLab to Koding
+    (`Run/Try on IDE (Koding)` buttons on GitLab Projects, Issues, MRs)
+
+As it's pointed out before, you will need public access to this machine that
+you've installed Koding and GitLab on. Better to use a domain but a static IP
+is also fine.
+
+For IP based installation you can use [xip.io](https://xip.io) service which is
+free and provides DNS resolution to IP based requests like following;
+
+  - 127.0.0.1.xip.io              -> resolves to 127.0.0.1
+  - foo.bar.baz.127.0.0.1.xip.io  -> resolves to 127.0.0.1
+  - and so on...
+
+As Koding needs subdomains for team names; `foo.127.0.0.1.xip.io` requests for
+a running koding instance on `127.0.0.1` server will be handled as `foo` team
+requests.
+
+
+### GitLab Side
+
+You need to enable Koding integration from Settings under Admin Area. To do
+that login with an Admin account and do followings;
+
+ - open [http://127.0.0.1:3000/admin/application_settings](http://127.0.0.1:3000/admin/application_settings)
+ - scroll to bottom of the page until Koding section
+ - check `Enable Koding` checkbox
+ - provide GitLab team page for running Koding instance as `Koding URL`*
+
+* For `Koding URL` you need to provide the gitlab integration enabled team on
+your Koding installation. Team called `gitlab` has integration on Koding out
+of the box, so if you didn't change anything your team on Koding should be
+`gitlab`.
+
+So, if your Koding is running on `http://1.2.3.4.xip.io:8090` your URL needs
+to be `http://gitlab.1.2.3.4.xip.io:8090`. You need to provide the same host
+with your Koding installation here.
+
+
+#### Registering Koding for OAuth integration
+
+We need `Application ID` and `Secret` to enable login to Koding via GitLab
+feature and to do that you need to register running Koding as a new application
+to your running GitLab application. Follow
+[these](http://docs.gitlab.com/ce/integration/oauth_provider.html) steps to
+enable this integration.
+
+Redirect URI should be `http://gitlab.127.0.0.1:8090/-/oauth/gitlab/callback`
+which again you need to _replace `127.0.0.1` with your instance public IP._
+
+Take a copy of `Application ID` and `Secret` that is generated by the GitLab
+application, we will need those on _Koding Part_ of this guide.
+
+
+#### Registering system hooks to Koding (optional)
+
+Koding can take actions based on the events generated by GitLab application.
+This feature is still in progress and only following events are processed by
+Koding at the moment;
+
+  - user_create
+  - user_destroy
+
+All system events are handled but not implemented on Koding side.
+
+To enable this feature you need to provide a `URL` and a `Secret Token` to your
+GitLab application. Open your admin area on your GitLab app from
+[http://127.0.0.1:3000/admin/hooks](http://127.0.0.1:3000/admin/hooks)
+and provide `URL` as `http://gitlab.127.0.0.1:8090/-/api/gitlab` which is the
+endpoint to handle GitLab events on Koding side. Provide a `Secret Token` and
+keep a copy of it, we will need it on _Koding Part_ of this guide.
+
+_(replace `127.0.0.1` with your instance public IP)_
+
+
+### Koding Part
+
+If you followed the steps in GitLab part we should have followings to enable
+Koding part integrations;
+
+  - `Application ID` and `Secret` for OAuth integration
+  - `Secret Token` for system hook integration
+  - Public address of running GitLab instance
+
+
+#### Start Koding with GitLab URL
+
+Now we need to configure Koding with all this information to get things ready.
+If it's already running please stop koding first.
+
+##### From command-line
+
+Replace followings with the ones you got from GitLab part of this guide;
+
+```bash
+cd koding
+docker-compose run                              \
+  --service-ports backend                       \
+  /opt/koding/scripts/bootstrap-container build \
+  --host=**YOUR_IP**.xip.io                     \
+  --gitlabHost=**GITLAB_IP**                    \
+  --gitlabPort=**GITLAB_PORT**                  \
+  --gitlabToken=**SECRET_TOKEN**                \
+  --gitlabAppId=**APPLICATION_ID**              \
+  --gitlabAppSecret=**SECRET**
+```
+
+##### By updating configuration
+
+Alternatively you can update `gitlab` section on
+`config/credentials.default.coffee` like following;
+
+```
+gitlab =
+  host: '**GITLAB_IP**'
+  port: '**GITLAB_PORT**'
+  applicationId: '**APPLICATION_ID**'
+  applicationSecret: '**SECRET**'
+  team: 'gitlab'
+  redirectUri: ''
+  systemHookToken: '**SECRET_TOKEN**'
+  hooksEnabled: yes
+```
+
+and start by only providing the `host`;
+
+```bash
+cd koding
+docker-compose run                              \
+  --service-ports backend                       \
+  /opt/koding/scripts/bootstrap-container build \
+  --host=**YOUR_IP**.xip.io                     \
+```
+
+#### Enable Single Sign On
+
+Once you restarted your Koding and logged in with your username and password
+you need to activate oauth authentication for your user. To do that
+
+ - Navigate to Dashboard on Koding from;
+   `http://gitlab.**YOUR_IP**.xip.io:8090/Home/my-account`
+ - Scroll down to Integrations section
+ - Click on toggle to turn On integration in GitLab integration section
+
+This will redirect you to your GitLab instance and will ask your permission (
+if you are not logged in to GitLab at this point you will be redirected after
+login) once you accept you will be redirected to your Koding instance.
+
+From now on you can login by using `SIGN IN WITH GITLAB` button on your Login
+screen in your Koding instance.

lib/gitlab/current_settings.rb

@@ -30,6 +30,7 @@ module Gitlab
         signup_enabled: Settings.gitlab['signup_enabled'],
         signin_enabled: Settings.gitlab['signin_enabled'],
         gravatar_enabled: Settings.gravatar['enabled'],
+        koding_enabled: false,
         sign_in_text: nil,
         after_sign_up_text: nil,
         help_page_text: nil,

spec/features/security/dashboard_access_spec.rb

@@ -43,6 +43,20 @@ describe "Dashboard access", feature: true  do
     it { is_expected.to be_allowed_for :visitor }
   end
 
+  describe "GET /koding" do
+    subject { koding_path }
+
+    context 'with Koding enabled' do
+      before do
+        stub_application_setting(koding_enabled?: true)
+      end
+
+      it { is_expected.to be_allowed_for :admin }
+      it { is_expected.to be_allowed_for :user }
+      it { is_expected.to be_denied_for :visitor }
+    end
+  end
+
   describe "GET /projects/new" do
     it { expect(new_project_path).to be_allowed_for :admin }
     it { expect(new_project_path).to be_allowed_for :user }

spec/routing/routing_spec.rb

@@ -116,12 +116,19 @@ describe HelpController, "routing" do
     expect(get(path)).to route_to('help#show',
                                   path: 'workflow/protected_branches/protected_branches1',
                                   format: 'png')
-    
+
     path = '/help/ui'
     expect(get(path)).to route_to('help#ui')
   end
 end
 
+#                      koding GET    /koding(.:format)                      koding#index
+describe KodingController, "routing" do
+  it "to #index" do
+    expect(get("/koding")).to route_to('koding#index')
+  end
+end
+
 #             profile_account GET    /profile/account(.:format)             profile#account
 #             profile_history GET    /profile/history(.:format)             profile#history
 #            profile_password PUT    /profile/password(.:format)            profile#password_update