Jenkins pipeline how to use string interpolation correctly-CodePudding

In my docker run, I would like to pass a secret as an env variable. And that works just fine. However, I also have a second variable "foo" that I would like to echo inside my container. This does not work. How can I get the variable "foo" to expand inside the triple single quotes?

 stages {
        stage('test') {
            steps {
                    script {
                        def foo = "bar"
                        sh '''
                        docker run \
                                --rm \
                                --env secret=$ENV_SECRET \
                                python:3.8.12 /bin/bash -c \
                                "echo $foo"
                        '''
                    
                }
                
            }
        }
    }

CodePudding user response：

The syntax for interpolating strings with Groovy variables in Groovy involves ". If your ENV_SECRET is an environment variable bound from a withCredentials block, then you want to interpolate it within the shell interpreter. Therefore, we can update your shell step method with:

sh """
  docker run \
  --rm \
  --env secret=\$ENV_SECRET \
  python:3.8.12 /bin/bash -c \
  'echo $foo'
"""

Your syntax would have interpolated shell variables instead. Note that both will interpolate environment variables, but with different interpreters.