Run Jenkins in a Docker container fails with script.sh: docker: not found

Question

I tried to build a simple JS app in Jenkins Docker container locally and the build failed with:

script.sh: docker: not found (full stack trace is omitted for easier reading)

Here is Jenkinsfile of the app:

pipeline {
  agent { dockerfile true }

  stages {
    stage('Install') {
      steps {
        sh 'node -v '      
        sh 'yarn -v'
        sh 'ember -v'

      }
    }
  }
}

Here is Dockerfile of the app:

FROM node:12

RUN curl -o- -L https://yarnpkg.com/install.sh | bash
RUN npm install -g ember-cli

What am I missing? Thank you.

Answer 1

You're missing the docker client on your Jenkins nodes.

If you're running Jenkins as docker container, you have to install Docker inside it as well.

This Dockerfile will use a Jenkins container as a base image and then install the docker client , So that it can communicate with the docker daemon.

from jenkinsci/jenkins:lts

USER root
RUN apt-get update -qq \
    && apt-get install -qqy apt-transport-https ca-certificates curl gnupg2 software-properties-common 
RUN curl -fsSL https://download.docker.com/linux/debian/gpg | apt-key add -
RUN add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/debian \
   $(lsb_release -cs) \
   stable"
RUN apt-get update  -qq \
    && apt-get install docker-ce=17.12.1~ce-0~debian -y
RUN usermod -aG docker jenkins

Or if you're installing Jenkins in another way, you still have to install Docker on Jenkins node.