Building Node.js and React.js using Jenkins - node.js

Question

I am following the official tutorial from Jenkins website. I have a blueocean Docker container that is running the pipeline in the Jenkinsfile as per tutorial:
pipeline {
agent {
docker {
image 'node:6-alpine'
args '-p 3000:3000'
}
}
stages {
stage('Build') {
steps {
sh 'npm install'
}
}
}
}
The problem is that the pipeline fails when it tries to pull the Docker image:
[ode-js-react-npm-app_master-6PEWX3VWDA4SAdDMJA4YKJCZSABJSAQCSGVYMKHINXGDDJLA] Running shell script
+ docker pull node:6-alpine
Warning: failed to get default registry endpoint from daemon (Cannot connect to the Docker daemon. Is the docker daemon running on this host?). Using system default: https://index.docker.io/v1/
Cannot connect to the Docker daemon. Is the docker daemon running on this host?
script returned exit code 1
After some troubleshooting, I realized that this is failing because Jenkins is trying to pull the Docker container itself, rather than the host. This is not what I want, and the documentation in fact states:
This image parameter (of the agent section’s docker parameter) downloads the node:6-alpine Docker image (if it’s not already available on your machine) and runs this image as a separate container. This means that:
You’ll have separate Jenkins and Node containers running locally in Docker.
The Node container becomes the agent that Jenkins uses to run your Pipeline project. However, this container is short-lived - its lifespan is only that of the duration of your Pipeline’s execution.
Can someone explain what I am doing wrong and why the Node.js Docker image is tried being pulled inside Jenkins instead of the local machine? I want to have a separate Jenkins container from the Nodejs container that orchestrates the app.

Answer 1

I solved this problem by running the container as root, as otherwise it would not have access to the Docker daemon socket /var/run/docker.sock ...