How do you tie two different build pipelines together in Jenkins? - jenkins

Question

I have a build pipeline in jenkins that builds and deploys the back-end components which expose a REST API. I have another build pipeline that builds and deploys the front-end components which call the back-end components. The back-end and front-end components live in seperate Git repositories.
The build job of each pipeline is kicked off when a commit occurs in each respective Git repository.
I would like to run automated functional tests at the end of the build pipeline of each build pipeline. But how do I know that both pipelines are finished and it should run the functional tests? Can it link the two pipelines together?

Answer 1

One approach is to use the Locks and Latches plugin and give each of the jobs on each pipeline their own Lock eg Pipeline-A and Pipeline-B, then the job that runs the tests is configured to obtain the lock on both Pipeline-A and Pipeline-B. This both prevents the test job running if any part of either pipeline is running, and blocks any changes on the pipeline whilst the tests are running.
If you'd only like to lock on the deploy jobs, you can use the same approach but only configure the deploy jobs with the locks; this will allow normal builds to run as normal, but deploy jobs queue up whilst the tests run.
Assumptions;
Any Deploy jobs are triggering a test execution
A second approach is to have your job pipelines setup such that before performing a deployment they trigger a single job in the following layout;
EndOfPipelineA -> SystemDeploymentController
EndOfPipelineB -> SystemDeploymentController
SystemDeploymentController -> DeployAppOne
SystemDeploymentController -> DeployAppTwo
DeployAppTwo -> TestExecution
DeployAppOne -> TestExecution
Then you use the Join plugin to only run the TestExecution job when both the deployments are complete AND successful.
The second approach allows you to:
conditionally control the execution of the test execution depending on the success of
deployments,
Have a single job that'll let you redeploy your whole system if you make any changes to the system it runs on, AND then run tests automatically.
Potentially make use of the Promotions plugin to highlight "good configurations" where both apps worked well together
However it is a bit trickier to manage.

Answer 2

Although this is an old question, you might consider restructuring your build pipeline using the Build Flow Plugin
https://wiki.jenkins-ci.org/display/JENKINS/Build+Flow+Plugin
It will have the advantage of keeping your pipeline logic in one place.

Answer 3

You can use build step for this. Let's say you have a pipeline named parent and child. In parent pipeline you can define:
pipeline {
agent any
stages {
stage ('call-child-pipeline') {
steps {
build job: 'child'
}
}
}
}
you can also pass some parameters to the child pipeline:
stage ('call-child-pipeline') {
steps {
build job: 'child', parameters: [string(name: 'my_param', value: "my_value")]
}
}
if you don't want to wait until the child pipeline is finished, add wait: false, e.g.
build job: 'child', wait: false