Create a Multi-branch Pipeline with GitLab

GitLab is an open source code repository platform that provides public and private repositories. It is a complete DevOps platform that enables professionals to perform their tasks in a project.

In KubeSphere 3.1.x and later, you can create a multi-branch pipeline with GitLab in your DevOps project. This tutorial demonstrates how to create a multi-branch pipeline with GitLab.

Prerequisites

• You need to have a GitLab account and a Docker Hub account.
• You need to enable the KubeSphere DevOps system.
• You need to create a workspace, a DevOps project and a user (project-regular). This user must be invited to the DevOps project with the operator role. For more information, refer to Create Workspaces, Projects, Users and Roles.

Hands-on Lab

Step 1: Create credentials

1. Log in to the KubeSphere console as project-regular. Go to your DevOps project and create the following credentials in Credentials under DevOps Project Settings. For more information about how to create credentials, see Credential Management.

   Note

   If there are any special characters such as @ and $ in your account or password, they can cause errors as a pipeline runs because they may not be recognized. In this case, you need to encode your account or password on some third-party websites first, such as urlencoder. After that, copy and paste the output for your credential information.

   Credential ID	Type	Where to use
   dockerhub-id	Account Credentials	Docker Hub
   gitlab-id	Account Credentials	GitLab
   demo-kubeconfig	kubeconfig	Kubernetes

2. After creation, you can see the credentials in the list.

Step 2: Modify the Jenkinsfile in your GitLab repository

1. Log in to GitLab and create a public project. Click Import project/repository, select Repo by URL to enter the URL of devops-maven-sample, select Public for Visibility Level, and then click Create project.

2. In the project just created, create a new branch from the master branch and name it gitlab-demo.

3. In the gitlab-demo branch, click the file Jenkinsfile-online in the root directory.

4. Click Edit, change GITHUB_CREDENTIAL_ID, GITHUB_ACCOUNT, and @github.com to GITLAB_CREDENTIAL_ID, GITLAB_ACCOUNT, and @gitlab.com respectively, and then edit the following items. You also need to change the value of branch in the push latest and deploy to dev stages to gitlab-demo.

   Item	Value	Description
   GITLAB_CREDENTIAL_ID	gitlab-id	The Name you set in KubeSphere for your GitLab account. It is used to push tags to your GitLab repository.
   DOCKERHUB_NAMESPACE	felixnoo	Replace it with your Docker Hub’s account name. It can be the Organization name under the account.
   GITLAB_ACCOUNT	felixnoo	Replace it with your GitLab account name. It can also be the account’s Group name.

   Note

   For more information about the environment variables in the Jenkinsfile, refer to Create a Pipeline Using a Jenkinsfile.

5. Click Commit changes to update this file.

Step 3: Create projects

You need to create two projects, such as kubesphere-sample-dev and kubesphere-sample-prod, which represent the development environment and the production environment respectively. For more information, refer to Create a Pipeline Using a Jenkinsfile.

Step 4: Create a pipeline

1. Log in to the KubeSphere web console as project-regular. Go to your DevOps project and click Create to create a new pipeline.

2. Provide the basic information in the displayed dialog box. Name it gitlab-multi-branch and select a code repository.

3. On the GitLab tab, select the default option https://gitlab.com for GitLab Server Address, enter the username of the GitLab project owner for Project Group/Owner, and then select the devops-maven-sample repository from the drop-down list for Code Repository. Click √ in the lower-right corner and then click Next.

   Note

   If you want to use a private repository from GitLab, refer to the following steps:

   • Go to User Settings > Access Tokens on GitLab to create an access token with API and read_repository permissions.
   • Log in to the Jenkins dashboard, go to Manage Jenkins > Manage Credentials to use your GitLab token to create a Jenkins credential for accessing GitLab, and go to Manage Jenkins > Configure System to add the credential in GitLab Server.
   • In your DevOps project, select DevOps Project Settings > Credentials to use your GitLab token to create a credential. You have to specify the credential for Credential on the GitLab tab when creating a pipeline so that the pipeline can pull code from your private GitLab repository.

4. On the Advanced Settings tab, scroll down to Script Path. Change it to Jenkinsfile-online and then click Create.

   Note

   The field specifies the Jenkinsfile path in the code repository. It indicates the repository’s root directory. If the file location changes, the script path also needs to be changed.

Step 5: Run a pipeline

1. After a pipeline is created, it is displayed in the list. Click its name to go to its details page.

2. Click Run on the right. In the displayed dialog box, select gitlab-demo from the drop-down list and add a tag number such as v0.0.2. Click OK to trigger a new run.

   Note

   The pipeline pauses at the stage deploy to dev. You need to click Proceed manually. Note that the pipeline will be reviewed three times as deploy to dev, push with tag, and deploy to production are defined in the Jenkinsfile respectively.

Step 6: Check the pipeline status

1. In the Task Status tab, you can see how a pipeline is running. Check the pipeline running logs by clicking View Logs in the upper-right corner.

2. You can see the dynamic log output of the pipeline, including any errors that may stop the pipeline from running. For each stage, you can click it to inspect logs, which can also be downloaded to your local machine for further analysis.

Step 7: Verify results

1. The Docker image built through the pipeline has been successfully pushed to Docker Hub, as it is defined in the Jenkinsfile. In Docker Hub, you will find the image with the tag v0.0.2 that is specified before the pipeline runs.

2. At the same time, a new tag is generated in GitLab.

3. The sample application will be deployed to kubesphere-sample-dev and kubesphere-sample-prod with corresponding Deployments and Services created.

   Environment	URL	Namespace	Deployment	Service
   Development	http://{$NodeIP}:{$30861}	kubesphere-sample-dev	ks-sample-dev	ks-sample-dev
   Production	http://{$NodeIP}:{$30961}	kubesphere-sample-prod	ks-sample	ks-sample

   Note

   You may need to open the port in your security groups so that you can access the app with the URL. For more information, refer to Access the example Service.