Merge branch 'external-omniauth-providers' into 'master'

Allow Omniauth providers to be marked as external

Related to #4009 

With this MR we will be able to allow the user to set which Omniauth Providers they would like to have as external. All users login in via these providers will be marked as external, even if they already had an account before. If the provider is removed form the list of external providers, the users will be marked as internal at their next login.

MR for Omnibus: gitlab-org/omnibus-gitlab!727

/cc @dblessing @DouweM 

See merge request !3657

1 files changed, 23 insertions, 0 deletions

diff --git a/doc/integration/omniauth.md b/doc/integration/omniauth.md
index 25f35988305..cab329c0dec 100644
--- a/doc/integration/omniauth.md
+++ b/doc/integration/omniauth.md
@@ -120,6 +120,29 @@ OmniAuth provider for an existing user.
 
 The chosen OmniAuth provider is now active and can be used to sign in to GitLab from then on.
 
+## Configure OmniAuth Providers as External
+
+>**Note:**
+This setting was introduced with version 8.7 of GitLab
+
+You can define which OmniAuth providers you want to be `external` so that all users
+creating accounts via these providers will not be able to have access to internal
+projects. You will need to use the full name of the provider, like `google_oauth2`
+for Google. Refer to the examples for the full names of the supported providers.
+
+**For Omnibus installations**
+
+```ruby
+  gitlab_rails['omniauth_external_providers'] = ['twitter', 'google_oauth2']
+```
+
+**For installations from source**
+
+```yaml
+  omniauth:
+    external_providers: ['twitter', 'google_oauth2']
+```
+
 ## Using Custom Omniauth Providers
 
 >**Note:**