Docker Jenkins Pipeline install global NPM packages

Question

I'm new to Docker/Jenkins.

Jenkins triggers the container via

docker run -t -d -u 995:315 -w /workspace/projectname -v /workspace/projectname:/workspace/projectname:rw,z -v /workspace/projectname@tmp:/workspace/projectname@tmp:rw,z  circleci/node:latest

My Pipeline

pipeline {
    agent {
        docker {
            image 'circleci/node:latest'
        }
    }
    environment { 
        HOME="."
        NPM_CONFIG_PREFIX="${pwd()}/.npm-global"
        PATH="$PATH:${pwd()}/.npm-global/bin:${pwd tmp: true}/.npm-global/bin"
    }
    stages {
        stage('NPM Config') {
            steps {
                sh 'npm install -g @angular/cli'
                echo "PATH is: $PATH"
                sh '.npm-global/bin/ng version'
                sh '/workspace/projectname/.npm-global/bin/ng version'
                sh 'ng version'
            }
        }
    }
}

echo "PATH is: $PATH" prints out

PATH is: /sbin:/usr/sbin:/bin:/usr/bin;/usr/bin/;/etc/;/etc/ssh/ssh/:/workspace/projectname/.npm-global/bin:/workspace/projectname@tmp/.npm-global/bin

Both of these

sh '.npm-global/bin/ng version'
sh '/workspace/projectname/.npm-global/bin/ng version'

do what I expect sh 'ng version' to do. However, sh 'ng version' gives me the following error

ng version
/workspace/projectname@tmp/durable-9f9bc04a/script.sh: 2: /workspace/projectname@tmp/durable-9f9bc04a/script.sh: ng: not found

I'm trying to avoid having to build my own image, what would be a good next step?

Also I would just use npx, but I would need to change a lot of repos and their scripts just to make this work and I would prefer to not do that.

UPDATE: It looks like the pipeline is ignoring changes the the PATH environment variable under

environment { 
   HOME="."
   NPM_CONFIG_PREFIX="${pwd()}/.npm-global"
   PATH="/foo/bar"
}

Is there a special may to modify the PATH? or maybe a permission issue?

Answer 1

If you use declarative pipelines for the build it`s no sense to install anything globally.

If you install 'angular-cli' during the pipeline execution npm will set PATH variable for you and ng will be available.

Global installation makes sense if you build your own image and plan to reuse it later. But in this case, the image will be deleted after the build.

In such cases, I use sh "ls -la1 $dir_name" or sh "whereis ng" to debug "executable not found" problems.

Also if you use а declarative pipeline you can use lightest images without CI bindings. I use node:8.11.3-stretch

Answer 2

Here is a formatted, hopefully useful answer, after trying to sort things out with their verbose documentation.

First off, the environment block declares Jenkins-level key-value pairs:

• Jenkins level is not workspace level, variable interpolation level is selected depending on the type of quotes, so if I understood properly:

  echo '$PATH' would show the workspace PATH ("default", in your case)

  echo "$PATH" would be interpreted by Jenkins, hence showing the "modified" PATH

• key-value pairs only are valid: even though it looks like shell environment variable setting, you could also write PATH = something whereas spaces around = wouldn't work in shell

It seems to have been thought mainly to expose parameters without the workspace knowing them, like a user would interactively give information (they talk a lot about credentials).

Second, only a limited list of steps makes valid calls, and there is no export step.

But there is a withEnv step that should do the job. I didn't find any example of it in a declarative pipeline { ... }, only in scripted node { ... } blocks, the declarative version's definition states that all steps are valid. And I found an example of a step wrapping a stage block (in a node though), so let's hope it's the same for stages (otherwise you'd have to specify withEnv on each stage - or as another wrapper inside a stage - that requires your environment mods: surely feasible yet so boring).

Something like this should work, or at least deserves a try:

  pipeline {
    agent { ... }
    environment { 
      HOME="."
      NPM_CONFIG_PREFIX="${pwd()}/.npm-global"
      PATH="$PATH:${pwd()}/.npm-global/bin:${pwd tmp: true}/.npm-global/bin"
    }
    withEnv(["PATH=$PATH", /*or*/ "PATH=${PATH}", /*or*/ "PATH+NPM=${pwd()}/.npm-global/bin:${pwd tmp: true}/.npm-global/bin"]) {
      stages {
        stage('NPM Config') {
          steps { ... }
        }
        stage('something else that needs ng') { ... }
      }
    }
  }

Well, you get the idea.

Finally, if this PATH thing doesn't work and is bothering you more than rewriting the pipeline, using the scripted alternative with node blocks might be interesting and way more flexible.

I'd love some feedback on that, from the OP or any Jenkins guru around!

Answer 3

The right way to do this is to use the Node.js plugin for Jenkins. It allows you to manage different versions of node and npm packages without installing them on the build machine manually. This is a configuration example to use node 13 and eslint globally:

In your pipeline then you can do this:

stage('Use node commands and npm packages') {
  steps {
    nodejs(nodeJSInstallationName: 'node13') {
      sh 'npm -v'  //substitute with your code
      sh 'node -v'
      sh 'eslint ...'
    }
  }
}

For the complete example: https://pillsfromtheweb.blogspot.com/2020/05/how-to-use-different-nodejs-versions-on.html