jenkins-pipeline in order to use docker

In jenkins in the pipeline, it is jenkinsfile file, if you want to call docker to build the image, complete the following tasks!

Add docker in tools {} is a failure, which I find a lot of information, and finally the environment variable env need to solve the problem.

• We need to add a global variable items, such as name docker, the path / usr / local
• Jenkinsfile add a file, used to run the command docker

pipeline {
 agent any
 tools{
    gradle "gradle"
 }

stages {
    stage('init') {
           steps {
            script{
              def dockerPath = tool 'docker' //全局配置里的docker
              env.PATH = "${dockerPath}/bin:${env.PATH}" //添加了系统环境变量上
            }
           }
    }

    stage('Build') {
        steps {
            script{
              sh "docker --version"
            }
        }
    }
  }
}

Note: We need to add the path to the docker env environment variable before you can use docker command, I tried this many times.