Issue

• I would like to create a Pipeline that runs parallel task in the same way a Matrix job does

Environment

• Jenkins
• CloudBees Jenkins Enterprise
• Pipeline Plugin
• Pipeline Stage View Plugin
• [Blue Ocean]

Related Issues

• JENKINS-27395
• JENKINS-33185
• JENKINS-38442

Resolution

You can run a pipeline that mocks the behavior of a Matrix jobs. You can trivially run the different combinations in parallel and express the structure like a Matrix.

In terms of Visualization however, Pipeline Stage View is not able to display the result in a Matrix structure. There are long standing improvment issues about this: JENKINS-27395 and JENKINS-33185.

Blue Ocean Plugin offer better visualization capabilities and is the way forward.

Example with “Flat” structure:

The following pipeline has 2 axises: Nodes and JDKs. Therefore there should be 4 tasks running in parallel:

• osx-agent-1 / jdk7: Runs on node “osx-agent-1” and use the tool “jdk7”
• osx-agent-1 / jdk8: Runs on node “osx-agent-1” and use the tool “jdk8”
• osx-agent-2 / jdk7: Runs on node “osx-agent-2” and use the tool “jdk7”
• osx-agent-2 / jdk8: Runs on node “osx-agent-2” and use the tool “jdk8”

def axisNode = ["osx-agent-1","osx-agent-2"]
def axisTool = ["jdk7","jdk8"]
def tasks = [:]

stage("Before") {
    node {
        echo "before"
    }
}

for(int i=0; i< axisNode.size(); i++) {
    def axisNodeValue = axisNode[i]
    for(int j=0; j< axisTool.size(); j++) {
        def axisToolValue = axisTool[j]
        tasks["${axisNodeValue}/${axisToolValue}"] = {
            node(axisNodeValue) {
                def javaHome = tool axisToolValue
                println "Node=${env.NODE_NAME}"
                println "Java=${javaHome}"
            }
        }
    }
}

stage ("Matrix") {
    parallel tasks
}

stage("After") {
    node {
        echo "after"
    }
}

Note that the “Matrix stage” is a simple parallel task and the matrix structure can be part of a bigger pipeline (as shown by this pipeline that is creating stages before and after the matrix structure).

Visualization in Blue Ocean

Example with “Nested” structure:

Another example is to run Nested Parallel tasks. The following pipeline do the exact same things except that we create a nest parallel tasks:

• “osx-agent-1”: Parent stage
  • osx-agent-1 / jdk7: Runs on node “osx-agent-1” and use the tool “jdk7”
  • osx-agent-1 / jdk8: Runs on node “osx-agent-1” and use the tool “jdk8”
• “osx-agent-2”: Parent stage
  • osx-agent-2 / jdk7: Runs on node “osx-agent-2” and use the tool “jdk7”
  • osx-agent-2 / jdk8: Runs on node “osx-agent-2” and use the tool “jdk8”

def axisNode = ["osx-agent-1","osx-agent-2"]
def axisTool = ["jdk7","jdk8"]
def tasks = [:]

stage("Before") {
    node {
        echo "before"
    }
}

for(int i=0; i< axisNode.size(); i++) {
    def axisNodeValue = axisNode[i]
    def subTasks = [:]
    for(int j=0; j< axisTool.size(); j++) {
        def axisToolValue = axisTool[j]
        subTasks["${axisNodeValue}/${axisToolValue}"] = {
            def javaHome = tool axisToolValue
            println "Node=${env.NODE_NAME}"
            println "Java=${javaHome}"
        }
    }
    tasks["${axisNodeValue}"] = {
        node(axisNodeValue) {
            parallel subTasks
        }
    }
}

stage ("Matrix") {
    parallel tasks
}

stage("After") {
    node {
        echo "after"
    }
}

Visualization in Blue Ocean

Note: Improvement for the visualization of Nested stages is an open issue, see JENKINS-38442