Merge branch 'master' of https://gitlab.com/gitlab-org/gitlab-ce into git-raw-workhorse

34 files changed, 57 insertions, 185 deletions

diff --git a/doc/integration/README.md b/doc/integration/README.md
index 5edac746c7b..83116bc8370 100644
--- a/doc/integration/README.md
+++ b/doc/integration/README.md
@@ -5,10 +5,10 @@ trackers and external authentication.
 
 See the documentation below for details on how to configure these services.
 
-- [Jira](jira.md) Integrate with the JIRA issue tracker
+- [Jira](../project_services/jira.md) Integrate with the JIRA issue tracker
 - [External issue tracker](external-issue-tracker.md) Redmine, JIRA, etc.
 - [LDAP](ldap.md) Set up sign in via LDAP
-- [OmniAuth](omniauth.md) Sign in via Twitter, GitHub, GitLab, and Google via OAuth.
+- [OmniAuth](omniauth.md) Sign in via Twitter, GitHub, GitLab.com, Google, Bitbucket, Facebook, Shibboleth, SAML, Crowd and Azure
 - [SAML](saml.md) Configure GitLab as a SAML 2.0 Service Provider
 - [CAS](cas.md) Configure GitLab to sign in using CAS
 - [Slack](slack.md) Integrate with the Slack chat service
diff --git a/doc/integration/external-issue-tracker.md b/doc/integration/external-issue-tracker.md
index 3543a67dd49..a2d7e922aad 100644
--- a/doc/integration/external-issue-tracker.md
+++ b/doc/integration/external-issue-tracker.md
@@ -19,7 +19,7 @@ To enable an external issue tracker you must configure the appropriate **Service
 Visit the links below for details:
 
 - [Redmine](../project_services/redmine.md)
-- [Jira](jira.md)
+- [Jira](../project_services/jira.md)
 
 ### Service Template
 
diff --git a/doc/integration/facebook.md b/doc/integration/facebook.md
index bc1f1673086..77bb75cbfca 100644
--- a/doc/integration/facebook.md
+++ b/doc/integration/facebook.md
@@ -19,7 +19,7 @@ something else descriptive.
 
 1. Enter the address of your GitLab installation at the bottom of the package
 
-    ![Facebook Website URL](facebook_website_url.png)
+    ![Facebook Website URL](img/facebook_website_url.png)
 
 1. Choose "Next"
 
@@ -29,7 +29,7 @@ something else descriptive.
 
 1. Fill in a contact email for your app
 
-    ![Facebook App Settings](facebook_app_settings.png)
+    ![Facebook App Settings](img/facebook_app_settings.png)
 
 1. Choose "Save Changes"
 
@@ -45,7 +45,7 @@ something else descriptive.
 
 1. You should now see an app key and app secret (see screenshot). Keep this page open as you continue configuration.
 
-    ![Facebook API Keys](facebook_api_keys.png)
+    ![Facebook API Keys](img/facebook_api_keys.png)
 
 1.  On your GitLab server, open the configuration file.
 
diff --git a/doc/integration/github.md b/doc/integration/github.md
index a789d2c814f..886784a27c9 100644
--- a/doc/integration/github.md
+++ b/doc/integration/github.md
@@ -22,7 +22,7 @@ GitHub will generate an application ID and secret key for you to use.
 
 1.  You should now see a Client ID and Client Secret near the top right of the page (see screenshot). 
     Keep this page open as you continue configuration.
-    ![GitHub app](github_app.png)
+    ![GitHub app](img/github_app.png)
 
 1.  On your GitLab server, open the configuration file.
 
diff --git a/doc/integration/gitlab.md b/doc/integration/gitlab.md
index 80e3c0142a0..b215cc7c609 100644
--- a/doc/integration/gitlab.md
+++ b/doc/integration/gitlab.md
@@ -28,7 +28,7 @@ GitLab.com will generate an application ID and secret key for you to use.
 
 1.  You should now see a Client ID and Client Secret near the top right of the page (see screenshot). 
     Keep this page open as you continue configuration. 
-    ![GitLab app](gitlab_app.png)
+    ![GitLab app](img/gitlab_app.png)
 
 1.  On your GitLab server, open the configuration file.
 
diff --git a/doc/integration/gmail_action_buttons_for_gitlab.md b/doc/integration/gmail_action_buttons_for_gitlab.md
index de45f25ad62..05a91d9bef9 100644
--- a/doc/integration/gmail_action_buttons_for_gitlab.md
+++ b/doc/integration/gmail_action_buttons_for_gitlab.md
@@ -4,7 +4,7 @@ GitLab supports [Google actions in email](https://developers.google.com/gmail/ma
 
 If correctly setup, emails that require an action will be marked in Gmail.
 
-![gmail_actions_button.png](gmail_actions_button.png)
+![gmail_actions_button.png](img/gmail_action_buttons_for_gitlab.png)
 
 To get this functioning, you need to be registered with Google.
 [See how to register with Google in this document.](https://developers.google.com/gmail/markup/registering-with-google)
diff --git a/doc/integration/google.md b/doc/integration/google.md
index 91e9b2495cc..f9a20dd840d 100644
--- a/doc/integration/google.md
+++ b/doc/integration/google.md
@@ -25,7 +25,7 @@ To enable the Google OAuth2 OmniAuth provider you must register your application
     - Application type: "Web Application"
     - Authorized JavaScript origins: This isn't really used by GitLab but go ahead and put 'https://gitlab.example.com' here.
     - Authorized redirect URI: 'https://gitlab.example.com/users/auth/google_oauth2/callback'
-1. Under the heading "Client ID for web application" you should see a Client ID and Client secret (see screenshot). Keep this page open as you continue configuration. ![Google app](google_app.png)
+1. Under the heading "Client ID for web application" you should see a Client ID and Client secret (see screenshot). Keep this page open as you continue configuration. ![Google app](img/google_app.png)
 
 1.  On your GitLab server, open the configuration file.
 
diff --git a/doc/integration/facebook_api_keys.png b/doc/integration/img/facebook_api_keys.png
index d6c44ac0f11..d6c44ac0f11 100644
--- a/doc/integration/facebook_api_keys.png
+++ b/doc/integration/img/facebook_api_keys.png
diff --git a/doc/integration/facebook_app_settings.png b/doc/integration/img/facebook_app_settings.png
index 30dd21e198a..30dd21e198a 100644
--- a/doc/integration/facebook_app_settings.png
+++ b/doc/integration/img/facebook_app_settings.png
diff --git a/doc/integration/facebook_website_url.png b/doc/integration/img/facebook_website_url.png
index dc3088bb2fa..dc3088bb2fa 100644
--- a/doc/integration/facebook_website_url.png
+++ b/doc/integration/img/facebook_website_url.png
diff --git a/doc/integration/github_app.png b/doc/integration/img/github_app.png
index d890345ced9..d890345ced9 100644
--- a/doc/integration/github_app.png
+++ b/doc/integration/img/github_app.png
diff --git a/doc/integration/gitlab_app.png b/doc/integration/img/gitlab_app.png
index 3f9391a821b..3f9391a821b 100644
--- a/doc/integration/gitlab_app.png
+++ b/doc/integration/img/gitlab_app.png
diff --git a/doc/integration/gmail_actions_button.png b/doc/integration/img/gmail_action_buttons_for_gitlab.png
index b08f54d137b..b08f54d137b 100644
--- a/doc/integration/gmail_actions_button.png
+++ b/doc/integration/img/gmail_action_buttons_for_gitlab.png
diff --git a/doc/integration/google_app.png b/doc/integration/img/google_app.png
index 5a62ad35009..5a62ad35009 100644
--- a/doc/integration/google_app.png
+++ b/doc/integration/img/google_app.png
diff --git a/doc/integration/img/jira_issue_reference.png b/doc/integration/img/jira_issue_reference.png
deleted file mode 100644
index 15739a22dc7..00000000000
--- a/doc/integration/img/jira_issue_reference.png
+++ /dev/null
diff --git a/doc/integration/img/jira_merge_request_close.png b/doc/integration/img/jira_merge_request_close.png
deleted file mode 100644
index 1e78daf105f..00000000000
--- a/doc/integration/img/jira_merge_request_close.png
+++ /dev/null
diff --git a/doc/integration/img/jira_project_name.png b/doc/integration/img/jira_project_name.png
deleted file mode 100644
index 5986fdb63fb..00000000000
--- a/doc/integration/img/jira_project_name.png
+++ /dev/null
diff --git a/doc/integration/img/jira_service.png b/doc/integration/img/jira_service.png
deleted file mode 100644
index 1f6628c4371..00000000000
--- a/doc/integration/img/jira_service.png
+++ /dev/null
diff --git a/doc/integration/img/jira_service_close_issue.png b/doc/integration/img/jira_service_close_issue.png
deleted file mode 100644
index 67dfc6144c4..00000000000
--- a/doc/integration/img/jira_service_close_issue.png
+++ /dev/null
diff --git a/doc/integration/img/jira_service_page.png b/doc/integration/img/jira_service_page.png
deleted file mode 100644
index 2b37eda3520..00000000000
--- a/doc/integration/img/jira_service_page.png
+++ /dev/null
diff --git a/doc/integration/img/jira_workflow_screenshot.png b/doc/integration/img/jira_workflow_screenshot.png
deleted file mode 100644
index 8635a32eb68..00000000000
--- a/doc/integration/img/jira_workflow_screenshot.png
+++ /dev/null
diff --git a/doc/integration/oauth_provider/admin_application.png b/doc/integration/img/oauth_provider_admin_application.png
index a5f34512aa8..a5f34512aa8 100644
--- a/doc/integration/oauth_provider/admin_application.png
+++ b/doc/integration/img/oauth_provider_admin_application.png
diff --git a/doc/integration/oauth_provider/application_form.png b/doc/integration/img/oauth_provider_application_form.png
index ae135db2627..ae135db2627 100644
--- a/doc/integration/oauth_provider/application_form.png
+++ b/doc/integration/img/oauth_provider_application_form.png
diff --git a/doc/integration/oauth_provider/authorized_application.png b/doc/integration/img/oauth_provider_authorized_application.png
index d3ce05be9cc..d3ce05be9cc 100644
--- a/doc/integration/oauth_provider/authorized_application.png
+++ b/doc/integration/img/oauth_provider_authorized_application.png
diff --git a/doc/integration/oauth_provider/user_wide_applications.png b/doc/integration/img/oauth_provider_user_wide_applications.png
index 719e1974068..719e1974068 100644
--- a/doc/integration/oauth_provider/user_wide_applications.png
+++ b/doc/integration/img/oauth_provider_user_wide_applications.png
diff --git a/doc/integration/twitter_app_api_keys.png b/doc/integration/img/twitter_app_api_keys.png
index 1076337172a..1076337172a 100644
--- a/doc/integration/twitter_app_api_keys.png
+++ b/doc/integration/img/twitter_app_api_keys.png
diff --git a/doc/integration/twitter_app_details.png b/doc/integration/img/twitter_app_details.png
index b95e8af8a74..b95e8af8a74 100644
--- a/doc/integration/twitter_app_details.png
+++ b/doc/integration/img/twitter_app_details.png
diff --git a/doc/integration/jira-integration-points.png b/doc/integration/jira-integration-points.png
deleted file mode 100644
index 0692a7b458a..00000000000
--- a/doc/integration/jira-integration-points.png
+++ /dev/null
diff --git a/doc/integration/jira.md b/doc/integration/jira.md
index de574d53410..78aa6634116 100644
--- a/doc/integration/jira.md
+++ b/doc/integration/jira.md
@@ -1,149 +1,3 @@
-# GitLab Jira integration
+# GitLab JIRA integration
 
-GitLab can be configured to interact with Jira. Configuration happens via
-username and password. Connecting to a Jira server via CAS is not possible.
-
-Each project can be configured to connect to a different Jira instance, see the
-[configuration](#configuration) section. If you have one Jira instance you can
-pre-fill the settings page with a default template. To configure the template
-see the [Services Templates][services-templates] document.
-
-Once the project is connected to Jira, you can reference and close the issues
-in Jira directly from GitLab.
-
-## Table of Contents
-
-* [Referencing Jira Issues from GitLab](#referencing-jira-issues)
-* [Closing Jira Issues from GitLab](#closing-jira-issues)
-* [Configuration](#configuration)
-
-### Referencing Jira Issues
-
-When GitLab project has Jira issue tracker configured and enabled, mentioning
-Jira issue in GitLab will automatically add a comment in Jira issue with the
-link back to GitLab. This means that in comments in merge requests and commits
-referencing an issue, eg. `PROJECT-7`, will add a comment in Jira issue in the
-format:
-
-```
- USER mentioned this issue in LINK_TO_THE_MENTION
-```
-
-* `USER` A user that mentioned the issue. This is the link to the user profile in GitLab.
-* `LINK_TO_THE_MENTION` Link to the origin of mention with a name of the entity where Jira issue was mentioned.
-Can be commit or merge request.
-
-![example of mentioning or closing the Jira issue](img/jira_issue_reference.png)
-
----
-
-### Closing Jira Issues
-
-Jira issues can be closed directly from GitLab by using trigger words, eg.
-`Resolves PROJECT-1`, `Closes PROJECT-1` or `Fixes PROJECT-1`, in commits and
-merge requests. When a commit which contains the trigger word in the commit
-message is pushed, GitLab will add a comment in the mentioned Jira issue.
-
-For example, for project named `PROJECT` in Jira, we implemented a new feature
-and created a merge request in GitLab.
-
-This feature was requested in Jira issue `PROJECT-7`. Merge request in GitLab
-contains the improvement and in merge request description we say that this
-merge request `Closes PROJECT-7` issue.
-
-Once this merge request is merged, the Jira issue will be automatically closed
-with a link to the commit that resolved the issue.
-
-![A Git commit that causes the Jira issue to be closed](img/jira_merge_request_close.png)
-
----
-
-![The GitLab integration user leaves a comment on Jira](img/jira_service_close_issue.png)
-
----
-
-## Configuration
-
-### Configuring JIRA
-
-We need to create a user in JIRA which will have access to all projects that
-need to integrate with GitLab. Login to your JIRA instance as admin and under
-Administration go to User Management and create a new user.
-
-As an example, we'll create a user named `gitlab` and add it to `jira-developers`
-group.
-
-**It is important that the user `gitlab` has write-access to projects in JIRA**
-
-### Configuring GitLab
-
-JIRA configuration in GitLab is done via a project's **Services**.
-
-#### GitLab 7.8 and up with JIRA v6.x
-
-See next section.
-
-#### GitLab 7.8 and up
-
-_The currently supported JIRA versions are v6.x and v7.x._
-
-To enable JIRA integration in a project, navigate to the project's
-**Settings > Services > JIRA**.
-
-Fill in the required details on the page as described in the table below.
-
-| Field | Description |
-| ----- | ----------- |
-| `description` | A name for the issue tracker (to differentiate between instances, for instance). |
-| `project url` | The URL to the JIRA project which is being linked to this GitLab project. |
-| `issues url`  | The URL to the JIRA project issues overview for the project that is linked to this GitLab project. |
-| `new issue url` | This is the URL to create a new issue in JIRA for the project linked to this GitLab project. |
-| `api url`     | The base URL of the JIRA API. It may be omitted, in which case GitLab will automatically use API version `2` based on the `project url`, i.e. `https://jira.example.com/rest/api/2`. |
-| `username` | The username of the user created in [configuring JIRA step](#configuring-jira). |
-| `password` |The password of the user created in [configuring JIRA step](#configuring-jira). |
-| `Jira issue transition` | This is the ID of a transition that moves issues to a closed state. You can find this number under JIRA workflow administration ([see screenshot](img/jira_workflow_screenshot.png)).  By default, this ID is `2` (in the example image, this is `2` as well) |
-
-After saving the configuration, your GitLab project will be able to interact
-with the linked JIRA project.
-
-![Jira service page](img/jira_service_page.png)
-
----
-
-#### GitLab 6.x-7.7 with JIRA v6.x
-
-_**Note:** GitLab versions 7.8 and up contain various integration improvements.
-We strongly recommend upgrading._
-
-In `gitlab.yml` enable the JIRA issue tracker section by
-[uncommenting these lines][jira-gitlab-yml]. This will make sure that all
-issues within GitLab are pointing to the JIRA issue tracker.
-
-After you set this, you will be able to close issues in JIRA by a commit in
-GitLab.
-
-Go to your project's **Settings** page and fill in the project name for the
-JIRA project:
-
-![Set the JIRA project name in GitLab to 'NEW'](img/jira_project_name.png)
-
----
-
-You can also enable the JIRA service that will allow you to interact with JIRA
-issues. Go to the **Settings > Services > JIRA** and:
-
-1. Tick the active check box to enable the service
-1. Supply the URL to JIRA server, for example http://jira.example.com
-1. Supply the username of a user we created under `Configuring JIRA` section,
-   for example `gitlab`
-1. Supply the password of the user
-1. Optional: supply the JIRA API version, default is version `2`
-1. Optional: supply the JIRA issue transition ID (issue transition to closed).
-   This is dependent on JIRA settings, default is `2`
-1. Hit save
-
-
-![Jira services page](img/jira_service.png)
-
-[services-templates]: ../project_services/services_templates.md
-[jira-gitlab-yml]: https://gitlab.com/subscribers/gitlab-ee/blob/6-8-stable-ee/config/gitlab.yml.example#L111-115
+This document was moved under [project_services/jira](../project_services/jira.md).
diff --git a/doc/integration/oauth_provider.md b/doc/integration/oauth_provider.md
index 192c321f712..dbe5a175c82 100644
--- a/doc/integration/oauth_provider.md
+++ b/doc/integration/oauth_provider.md
@@ -15,16 +15,16 @@ GitLab has two ways to add new OAuth2 application to an instance, you can add ap
 ### Adding application through profile
 Go to your profile section 'Application' and press button 'New Application'
 
-![applications](oauth_provider/user_wide_applications.png)
+![applications](img/oauth_provider_user_wide_applications.png)
 
 After this you will see application form, where "Name" is arbitrary name, "Redirect URI" is URL in your app where users will be sent after authorization on GitLab.com.
 
-![application_form](oauth_provider/application_form.png)
+![application_form](img/oauth_provider_application_form.png)
 
 ### Authorized application
 Every application you authorized will be shown in your "Authorized application" sections.
 
-![authorized_application](oauth_provider/authorized_application.png)
+![authorized_application](img/oauth_provider_authorized_application.png)
 
 At any time you can revoke access just clicking button "Revoke"
 
@@ -32,4 +32,4 @@ At any time you can revoke access just clicking button "Revoke"
 
 If you want to create application that does not belong to certain user you can create it from admin area 
 
-![admin_application](oauth_provider/admin_application.png)
\ No newline at end of file
+![admin_application](img/oauth_provider_admin_application.png)
diff --git a/doc/integration/omniauth.md b/doc/integration/omniauth.md
index e9e17eb4165..8e6627b2be5 100644
--- a/doc/integration/omniauth.md
+++ b/doc/integration/omniauth.md
@@ -9,6 +9,23 @@ Configuring OmniAuth does not prevent standard GitLab authentication or LDAP (if
 - [Enable OmniAuth for an Existing User](#enable-omniauth-for-an-existing-user)
 - [OmniAuth configuration sample when using Omnibus GitLab](https://gitlab.com/gitlab-org/omnibus-gitlab/tree/master#omniauth-google-twitter-github-login)
 
+## Supported Providers
+
+This is a list of the current supported OmniAuth providers. Before proceeding
+on each provider's documentation, make sure to first read this document as it
+contains some settings that are common for all providers.
+
+- [GitHub](github.md)
+- [Bitbucket](bitbucket.md)
+- [GitLab.com](gitlab.md)
+- [Google](google.md)
+- [Facebook](facebook.md)
+- [Twitter](twitter.md)
+- [Shibboleth](shibboleth.md)
+- [SAML](saml.md)
+- [Crowd](crowd.md)
+- [Azure](azure.md)
+
 ## Initial OmniAuth Configuration
 
 Before configuring individual OmniAuth providers there are a few global settings that are in common for all providers that we need to consider.
@@ -67,19 +84,6 @@ If you want to change these settings:
 
 Now we can choose one or more of the Supported Providers below to continue configuration.
 
-## Supported Providers
-
-- [GitHub](github.md)
-- [Bitbucket](bitbucket.md)
-- [GitLab.com](gitlab.md)
-- [Google](google.md)
-- [Facebook](facebook.md)
-- [Twitter](twitter.md)
-- [Shibboleth](shibboleth.md)
-- [SAML](saml.md)
-- [Crowd](crowd.md)
-- [Azure](azure.md)
-
 ## Enable OmniAuth for an Existing User
 
 Existing users can enable OmniAuth for specific providers after the account is created. For example, if the user originally signed in with LDAP an OmniAuth provider such as Twitter can be enabled. Follow the steps below to enable an OmniAuth provider for an existing user.
diff --git a/doc/integration/saml.md b/doc/integration/saml.md
index 1632e42f701..8841dbdb7c6 100644
--- a/doc/integration/saml.md
+++ b/doc/integration/saml.md
@@ -78,6 +78,18 @@ On the sign in page there should now be a SAML button below the regular sign in
 
 ## Troubleshooting
 
-If you see a "500 error" in GitLab when you are redirected back from the SAML sign in page, this likely indicates that GitLab could not get the email address for the SAML user.
+If you see a "500 error" in GitLab when you are redirected back from the SAML sign in page,
+this likely indicates that GitLab could not get the email address for the SAML user.
 
-Make sure the IdP provides a claim containing the user's email address, using claim name 'email' or 'mail'. The email will be used to automatically generate the GitLab username.
\ No newline at end of file
+Make sure the IdP provides a claim containing the user's email address, using claim name
+'email' or 'mail'. The email will be used to automatically generate the GitLab username.
+
+If after signing in into your SAML server you are redirected back to the sign in page and
+no error is displayed, check your `production.log` file. It will most likely contain the
+message `Can't verify CSRF token authenticity`. This means that there is an error during
+the SAML request, but this error never reaches GitLab due to the CSRF check.
+
+To bypass this you can add `skip_before_action :verify_authenticity_token` to the
+`omniauth_callbacks_controller.rb` file. This will allow the error to hit GitLab,
+where it can then be seen in the usual logs, or as a flash message in the login
+screen.
\ No newline at end of file
diff --git a/doc/integration/slack.md b/doc/integration/slack.md
index 84f1d74c058..ecbe0d3e887 100644
--- a/doc/integration/slack.md
+++ b/doc/integration/slack.md
@@ -6,15 +6,17 @@ To enable Slack integration you must create an Incoming WebHooks integration on
 
 1.  [Sign in to Slack](https://slack.com/signin)
 
-1.  Select **Configure Integrations** from the dropdown next to your team name.
+1.  Select **Apps & Custom Integrations** from the dropdown next to your team name.
 
-1.  Select the **All Services** tab
+1.  Click the **Configure** link (right-upper corner).
 
-1.  Click **Add** next to Incoming Webhooks
+1.  Select the **Custom integrations** tab.
 
-1.  Pick Incoming WebHooks
+1.  Click the **Incoming WebHooks** row.
 
-1.  Choose the channel name you want to send notifications to
+1.  Click the **Add configuration** button.
+
+1.  Choose the channel name you want to send notifications to.
 
 1.  Click **Add Incoming WebHooks Integration**
     - Optional step; You can change bot's name and avatar by clicking modifying the bot name or avatar under **Integration Settings**.
diff --git a/doc/integration/twitter.md b/doc/integration/twitter.md
index 52ed4a22339..4769f26b259 100644
--- a/doc/integration/twitter.md
+++ b/doc/integration/twitter.md
@@ -14,7 +14,7 @@ To enable the Twitter OmniAuth provider you must register your application with
     - Callback URL: 'https://gitlab.example.com/users/auth/twitter/callback'
     - Agree to the "Developer Agreement".
 
-    ![Twitter App Details](twitter_app_details.png)
+    ![Twitter App Details](img/twitter_app_details.png)
 1.  Select "Create your Twitter application."
 
 1.  Select the "Settings" tab.
@@ -27,7 +27,7 @@ To enable the Twitter OmniAuth provider you must register your application with
 
 1.  You should now see an API key and API secret (see screenshot). Keep this page open as you continue configuration.
 
-    ![Twitter app](twitter_app_api_keys.png)
+    ![Twitter app](img/twitter_app_api_keys.png)
 
 1.  On your GitLab server, open the configuration file.
 
@@ -76,4 +76,4 @@ To enable the Twitter OmniAuth provider you must register your application with
 
 1.  Restart GitLab for the changes to take effect.
 
-On the sign in page there should now be a Twitter icon below the regular sign in form. Click the icon to begin the authentication process. Twitter will ask the user to sign in and authorize the GitLab application. If everything goes well the user will be returned to GitLab and will be signed in.
\ No newline at end of file
+On the sign in page there should now be a Twitter icon below the regular sign in form. Click the icon to begin the authentication process. Twitter will ask the user to sign in and authorize the GitLab application. If everything goes well the user will be returned to GitLab and will be signed in.