Merge branch 'doc/harborintegration' into 'master'

Docs: Harbor Integration

See merge request gitlab-org/gitlab!80587

doc/user/project/integrations/harbor.md

+---
+stage: Ecosystem
+group: Integrations
+info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
+---
+
+# Harbor container registry integration **(FREE)**
+
+Use Harbor as the container registry for your GitLab project.
+
+[Harbor](https://goharbor.io/) is an open source registry that can help you manage artifacts across cloud native compute platforms, like Kubernetes and Docker.
+
+This integration can help you if you need GitLab CI/CD and a container image repository.
+
+## Prerequisites
+
+In the Harbor instance, ensure that:
+
+- The project to be integrated has been created.
+- The signed-in user has permission to pull, push, and edit images in the Harbor project.
+
+## Configure GitLab
+
+GitLab supports integrating Harbor projects at the group or project level. Complete these steps in GitLab:
+
+1. On the top bar, select **Menu > Projects** and find your project.
+1. On the left sidebar, select **Settings > Integrations**.
+1. Select **Harbor**.
+1. Turn on the **Active** toggle under **Enable Integration**.
+1. Provide the Harbor configuration information:
+   - **Harbor URL**: The base URL of Harbor instance which is being linked to this GitLab project. For example, `https://harbor.example.net`.
+   - **Harbor project name**: The project name in the Harbor instance. For example, `testproject`.  
+   - **Username**: Your username in the Harbor instance, which should meet the requirements in [prerequisites](#prerequisites).
+   - **Password**: Password of your username.
+
+1. Select **Save changes**.
+
+After the Harbor integration is activated:
+
+- The global variables `$HARBOR_USER`, `$HARBOR_PASSWORD`, `$HARBOR_URL`, and `$HARBOR_PROJECT` are created for CI/CD use.
+- The project-level integration settings override the group-level integration settings.
+
+## Secure your requests to the Harbor APIs
+
+For each API request through the Harbor integration, the credentials for your connection to the Harbor API use
+the `username:password` combination. The following are suggestions for safe use: 
+
+- Use TLS on the Harbor APIs you connect to.
+- Follow the principle of least privilege (for access on Harbor) with your credentials.
+- Have a rotation policy on your credentials.

doc/user/project/integrations/overview.md

@@ -43,6 +43,7 @@ Click on the service links to see further configuration instructions and details
 | [Flowdock](../../../api/integrations.md#flowdock)             | Send notifications from GitLab to Flowdock flows. | **{dotted-circle}** No |
 | [GitHub](github.md)                                       | Obtain statuses for commits and pull requests.                                               | **{dotted-circle}** No |
 | [Google Chat](hangouts_chat.md)                           | Send notifications from your GitLab project to a room in Google Chat.| **{dotted-circle}** No |
+| [Harbor](harbor.md)                           | Use Harbor as the container registry. | **{dotted-circle}** No |
 | [irker (IRC gateway)](irker.md)                           | Send IRC messages.                                                                           | **{dotted-circle}** No |
 | [Jenkins](../../../integration/jenkins.md)                | Run CI/CD pipelines with Jenkins.                                                            | **{check-circle}** Yes |
 | JetBrains TeamCity CI                                     | Run CI/CD pipelines with TeamCity.                                                           | **{check-circle}** Yes |