Jenkins Shared Library

What is jenkins shared library?

• In short, shared library is the set of common code that you can store in one place and reuse across any Jenkinsfile and github repositories.

• We can achieve DRY principle by using share libraries

• For more details, please read this doc - https://www.jenkins.io/doc/book/pipeline/shared-libraries/

Shared library location

• All the jenkins shared libraries are present here - https://github.com/project-sunbird/sunbird-devops/tree/shared-lib

• In jenkins, under the Manage Jenkins → Configuration page, there is a shared library section. We need to configure use the branch and repo in this configuration

Updating shared libraries

• When updating shared libraries, its not recommended to directly update the changes in the branch

• This has a large blast radius and can cause all the jenkins jobs to stop working, including adopter jenkins machines

• As a good practice, a new branch should be created and changes should be tested from this new branch

• The new branch can be configured on jenkins for a few days to ensure that the changes are working as expected and do not break any flows

• Once verified, the changes should be merged back to the shared-lib branch so that the community can also get the benefit of these changes

Shared Library Code Reference

• Jenkinsfile indicating the use of shared library - https://github.com/project-sunbird/sunbird-devops/blob/master/pipelines/provision/cassandra/Jenkinsfile#L1

  • This name should be configured on Jenkins also with the same name deploy-conf

• Invocation of one of the shared library - https://github.com/project-sunbird/sunbird-devops/blob/master/pipelines/provision/cassandra/Jenkinsfile#L36

  • To call the shared library, use the name of the file without the extension

• The shared library code that runs on invocation - https://github.com/project-sunbird/sunbird-devops/blob/shared-lib/vars/ansible_playbook_run.groovy

• Another shared library invocation reference - https://github.com/project-sunbird/sunbird-devops/blob/master/pipelines/provision/cassandra/Jenkinsfile#L48

• Another shared library code that runs on invocation - https://github.com/project-sunbird/sunbird-devops/blob/shared-lib/vars/slack_notify.groovy

• The share libraries work exactly like function calls of any programming language

• You can pass parameters / arguments and also return back values to callers from shared libraries

List of Shared Library Code

• All the shared library codes are located here - https://github.com/project-sunbird/sunbird-devops/tree/shared-lib/vars

• ansible_playbook_run.groovy

  • Clone private repo, copies the inventory to appropriate locations, runs the ansible playbook

• artifact_download.groovy

  • Downloads provided artifact from cloud storage

• auto_build_deploy.groovy

  • Used in staging automated deployments to automatically trigger the artifact upload and deploy jobs

• auto_build_deploy_player.groovy

  • Used in staging automated deployment of Player job to automatically trigger the artifact upload and deploy jobs

• copy_file_to_wksp.groovy

  • Allows a user to upload a file from Jenkinsjob and copy to workspace

• deployed_versions.groovy

  • Gives the list of jobs deployed in a release along with the tags (This job needs some enhancement. Currently the data returned is partially correct)

• docker_params.groovy

  • Used in container workload jenkins job to return information about few parameters to the caller

• email_notify.groovy

  • Used to send email notifications on the job status

• lp_dp_params.groovy

  • Used in non-container workload jenkins job to return information about few parameters to the caller

• pre_checks.groovy

  • Used in automated deployment jenkinsfiles to ensure the tag is an allowed tag for staging environment and the deployment is triggered in the allowed window / slots (start and end time)

• slack_notify.groovy

  • Used to send slack notifications on the job status

• stagingRC.groovy

  • Used in staging tag creation jenkinsfile to ensure the tag is an allowed tag for staging environment and the deployment is triggered in the allowed window / slots (start and end time)

• summary.groovy

  • Used to write the deployed jobs information in a file so that its easy to retrieve the list of deployed jobs in a particular release (this job can be enhanced to provide the data in an enhanced way so that it can be consumed without additional parsing)