How to Set Up Automation Build Triggers

Build Periodic

• Used to trigger the Jenkins jobs irrespective of code change.

• The build is scheduled based on the crontab

• It is not meant for CI/CD

How to set up build periodic trigger

• Go to any project in Jenkins and click on "Configure."

• Scroll down and look for the "Build Triggers" section.

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• Select Build periodically option

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• We can click on “?” for help in syntax of cron

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• We can also use this link: https://crontab.guru/ for help.

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• Enter the syntax in the field

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  • Here “ * * * * *” means build will run every minute.

• Click on "Apply" and then "Save."

• Build will execute every minute

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GitHub Webhook

• Used to trigger Jenkins job whenever there is any commit happened in the remote repository.

• GitHub Webhook has to be configured in the remote repository by using the Jenkins URL

• Used to implement CICD.

How to set GitHub Webhook trigger

• Go to any project in Jenkins and click on "Configure."

• Scroll down and look for the "Build Triggers" section.

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• Select “GitHub hook trigger for GITScm polling” option

• In the GitHub repository, click on the settings button.

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• From left menu click on Webhooks

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• Click on Add Webhook

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• In the ‘Payload URL’ field, paste your Jenkins environment URL. At the end of this URL add /github-webhook/. In the ‘Content type’ select: ‘application/json’ and leave the ‘Secret’ field empty. Click on “Add Webhook”.

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• Add the Webhook and commit the changes in the repository

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• Build gets executed as soon we commit the changes.

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PollSCM

• It is used to trigger the build based on the crontab only if there is any changes happened in the source-code repository.

  • i.e. if we set crontab to “* * * * *” and make some changes in source code repository, build will trigger based on the changes after every one minute.