Add Okta SCIM documentation

This documentation includes how to configure the new Okta GitLab
application.

doc/user/group/saml_sso/scim_setup.md

@@ -12,25 +12,28 @@ that group is synchronized between GitLab and the identity provider.
 
 GitLab's [SCIM API](../../../api/scim.md) implements part of [the RFC7644 protocol](https://tools.ietf.org/html/rfc7644).
 
+## Features
+
 Currently, the following actions are available:
 
-- CREATE
-- UPDATE
-- DELETE (deprovisioning)
+- Create users
+- Update users (Azure only)
+- Deactivate users
 
 The following identity providers are supported:
 
 - Azure
+- Okta
 
 ## Requirements
 
-- [Group SSO](index.md) must be configured.
+- [Group Single Sign-On](index.md) must be configured.
 
 ## GitLab configuration
 
-Once [Single sign-on](index.md) has been configured, we can:
+Once [Group Single Sign-On](index.md) has been configured, we can:
 
-1. Navigate to the group and click **Settings > SAML SSO**.
+1. Navigate to the group and click **Administration > SAML SSO**.
 1. Click on the **Generate a SCIM token** button.
 1. Save the token and URL so they can be used in the next step.
 
@@ -38,9 +41,12 @@ Once [Single sign-on](index.md) has been configured, we can:
 
 ## Identity Provider configuration
 
-### Azure
+- [Azure](#azure-configuration-steps)
+- [Okta](#okta-configuration-steps)
 
-The SAML application that was created during [Single sign-on](index.md) setup now needs to be set up for SCIM.
+### Azure configuration steps
+
+The SAML application that was created during [Single sign-on](index.md) setup for [Azure](https://docs.microsoft.com/en-us/azure/active-directory/manage-apps/configure-single-sign-on-non-gallery-applications) now needs to be set up for SCIM.
 
 1. Check the configuration for your GitLab SAML app and ensure that **Name identifier value** (NameID) points to `user.objectid` or another unique identifier. This will match the `extern_uid` used on GitLab.
 
@@ -109,6 +115,38 @@ bottom of the **Provisioning** screen, together with a link to the audit logs.
 CAUTION: **Warning:**
 Once synchronized, changing the field mapped to `id` and `externalId` will likely cause provisioning errors, duplicate users, and prevent existing users from accessing the GitLab group.
 
+### Okta configuration steps
+
+The SAML application that was created during [Single sign-on](index.md) setup for [Okta](The SAML application that was created during [Single sign-on](index.md) setup for [Okta](https://developer.okta.com/docs/guides/saml-application-setup/overview/) now needs to be set up for SCIM.
+
+1. Sign in to Okta.
+1. If you see an **Admin** button in the top right, click the button. This will
+   ensure you are in the Admin area.
+
+   TIP: **Tip:** If you're using the Developer Console, click **Developer Console** in the top
+   bar and select **Classic UI**. Otherwise, you may not see the buttons described
+   in the following steps:
+
+1. In the **Application** tab, click **Add Application**.
+1. Search for **GitLab**, find and click on the 'GitLab' application.
+1. On the GitLab application overview page, click **Add**.
+1. Under **Application Visibility** select both check boxes. Currently the GitLab application does not support SAML authentication so the icon should not be shown to users.
+1. Click **Done** to finish adding the application.
+1. In the **Provisioning** tab, click **Configure API integration**.
+1. Select **Enable API integration**.
+    - For **Base URL** enter the URL obtained from the GitLab SCIM configuration page
+    - For **API Token** enter the SCIM token obtained from the GitLab SCIM configuration page
+1. Click 'Test API Credentials' to verify configuration.
+1. Click **Save** to apply the settings.
+1. Assign users in the **Assignments** tab. Assigned users will be created and
+   managed in your GitLab group.
+
+#### Okta Known Issues
+
+The Okta GitLab application currently only supports SCIM. Continue
+using the separate Okta [SAML SSO](index.md) configuration along with the new SCIM
+application described above.
+
 ## User access and linking setup
 
 As long as [Group SAML](index.md) has been configured, prior to turning on sync, existing GitLab.com users can link to their accounts in one of the following ways, before synchronization is active:
@@ -135,7 +173,9 @@ Upon the next sync, the user will be deprovisioned, which means that the user wi
 
 This section contains possible solutions for problems you might encounter.
 
-### How do I verify my SCIM configuration is correct?
+### Azure
+
+#### How do I verify my SCIM configuration is correct?
 
 Review the following:
 
@@ -148,11 +188,11 @@ Review the following SCIM parameters for sensible values:
 - `displayName`
 - `emails[type eq "work"].value`
 
-### Testing Azure connection: invalid credentials
+#### Testing Azure connection: invalid credentials
 
 When testing the connection, you may encounter an error: **You appear to have entered invalid credentials. Please confirm you are using the correct information for an administrative account**. If `Tenant URL` and `secret token` are correct, check whether your group path contains characters that may be considered invalid JSON primitives (such as `.`). Removing such characters from the group path typically resolves the error.
 
-### Azure: (Field) can't be blank sync error
+#### Azure: (Field) can't be blank sync error
 
 When checking the Audit Logs for the Provisioning, you can sometimes see the
 error `Namespace can't be blank, Name can't be blank, and User can't be blank.`
@@ -165,14 +205,7 @@ As a workaround, try an alternate mapping:
 1. Delete the `name.formatted` target attribute entry.
 1. Change the `displayName` source attribute to have `name.formatted` target attribute.
 
-### Message: "SAML authentication failed: Email has already been taken"
-
-This message may be caused by the following:
-
-- Existing users have not yet signed into the new app.
-- The identity provider attempts to create a new user account in GitLab with an email address that already exists in GitLab.com.
-
-### How do I diagnose why a user is unable to sign in
+#### How do I diagnose why a user is unable to sign in
 
 The **Identity** (`extern_uid`) value stored by GitLab is updated by SCIM whenever `id` or `externalId` changes. Users won't be able to sign in unless the GitLab Identity (`extern_uid`) value matches the `NameId` sent by SAML.
 
@@ -180,7 +213,7 @@ This value is also used by SCIM to match users on the `id`, and is updated by SC
 
 It is important that this SCIM `id` and SCIM `externalId` are configured to the same value as the SAML `NameId`. SAML responses can be traced using [debugging tools](./index.md#saml-debugging-tools), and any errors can be checked against our [SAML troubleshooting docs](./index.md#troubleshooting).
 
-### How do I verify user's SAML NameId matches the SCIM externalId
+#### How do I verify user's SAML NameId matches the SCIM externalId
 
 Group owners can see the list of users and the `externalId` stored for each user in the group SAML SSO Settings page.
 
@@ -194,7 +227,7 @@ curl 'https://example.gitlab.com/api/scim/v2/groups/GROUP_NAME/Users?startIndex=
 
 To see how this compares to the value returned as the SAML NameId, you can have the user use a [SAML Tracer](index.md#saml-debugging-tools).
 
-### Update or fix mismatched SCIM externalId and SAML NameId
+#### Update or fix mismatched SCIM externalId and SAML NameId
 
 Whether the value was changed or you need to map to a different field, ensure `id`, `externalId`, and `NameId` all map to the same field.
 
@@ -220,7 +253,7 @@ curl --verbose --request PATCH 'https://gitlab.com/api/scim/v2/groups/YOUR_GROUP
 
 It is important not to update these to incorrect values, since this will cause users to be unable to sign in. It is also important not to assign a value to the wrong user, as this would cause users to get signed into the wrong account.
 
-### I need to change my SCIM app
+#### I need to change my SCIM app
 
 Individual users can follow the instructions in the ["SAML authentication failed: User has already been taken"](./index.md#i-need-to-change-my-saml-app) section.