Jenkins + github

Install and setup the project

Get the code from this github repository :

• The source code for this project is used to run a ready-to-use docker container.
• The setup.sh script is really simple.

# download the code
$ git clone \
    --depth 1 \
    https://github.com/jeromedecoster/note-jenkins-github.git \
    /tmp/note

# cd
$ cd /tmp/note

# docker pull jenkins
$ make setup

After the setup, we can now start the install :

• The install.sh script starts the first steps of the Jenkins installation. The rest will we done manually within the browser.
• The fully automated installation of Jenkins is a painful experience for me : many strange steps for a result that is never completely satisfactory. And this is clearly what software should avoid doing.

# create docker image with jenkins + plugins
$ make install

The docker image store all Jenkins data in a local directory :

• A volume link is created between /var/jenkins_home and a local directory /var/docker/jenkins-github our your computer.

docker run \
    --detach \
    --user 0 \
    --publish 8080:8080 \
    --publish 50000:50000 \
    --volume /var/docker/jenkins-github:/var/jenkins_home \
    --name jenkins-github \
    jenkins/jenkins:lts

You can open http://localhost:8080 to paste the password displayed in the terminal :

Now we choose to install the suggested plugins :

Let’s go have a coffee :

We create the admin user :

Let’s validate the Jenkins URL :

The basic installation is complete. But we must now install 2 additional plugins from the Plugin Manager area :

• Search github integration and choose Install without restart.

• Search nodejs and choose again Install without restart.

Now we need to configure NodeJS in the http://localhost:8080/configureTools/ area :

• We choose the LTS version and name the configuration node-v12.
• We check Install automatically and select a 12.x.x version.

Extra step, we can zip our docker local volume directory to save the current state of Jenkins :

# get the variables
$ source settings.sh

# go to our local volume directory
$ cd /var/docker/

# zip the local volume directory
$ sudo zip -r9 $NAME.zip $NAME

Configure Jenkins

Let’s create a new free-style project :

We will use a simple node project to test Jenkins. You can fork this project and setup the Git repository with your own URL :

Now we configure the lookup with a cron pattern : * * * * * means check every minute if there has been a new commit.

Then we define the NodeJS installation with our node-v12 configuration :

Now we can define a shell script to execute :

Simple things to execute :

npm install
npm test

The npm test is defined in the package.json file :

npx mocha './**/*.test.js'

This will execute this simple app.test.js file :

describe('/add', () => {

    it('success', (done) => {
        const a = 2
        const b = 4
        const expected = 6

        request(app)
            .post('/add')
            .send({ a, b })
            .set('Accept', 'application/json')
            .end((err, res) => {

                if (err) return done(err)

                const result = res.body.result
                if (result === expected) return done()

                done(new Error(`receive:${result} expected:${expected}`))
            })
    })

    // ...

The configuration is done. We save it. The we launch a build :

In Console Output we see the processing running :

Then it’s built with SUCCESS :

Let’s modifiate the app.js file directly in github :

We add an error :

return res.json({
    result: a + b + 1 // modification done here
})

We commit the error :

After a few seconds, a build is automatically started :

We choose Console Output from the contextual menu :

The process ends with our expected FAILURE :

Error: receive: 7 expected: 6