[FIXED] Jenkinsfile not building image from within a dind container

Issue

I have the following step of a Jenkinsfile stage that is initiated in a kubernetes jenkins and run from within a dind container (therefore the docker daemon is present)

    steps {
      echo 'building staging image'
      script {
        env.VERSION = readFile 'alerta/ci/ALERTA_BASE_VERSION'
      }
        echo "Bulding with alerta base version: ${env.VERSION}"
        sh 'docker build --tag alerta-local --build-arg ALERTA_BASE_VERSION=${env.VERSION} alerta-custom'
    }
  }

The echo "Bulding with alerta base version: ${env.VERSION}" is apparently executed, given that I see in the jenkins console:

21:55:57  Bulding with alerta base version: 8.0.2

However the pipeline ultimately fails with the following error:

21:55:59  /home/jenkins/agent/workspace/ebhook-pipeline_alerta_dev_infra@tmp/durable-606e41f8/script.sh: 1: /home/jenkins/agent/workspace/ebhook-pipeline_alerta_dev_infra@tmp/durable-606e41f8/script.sh: Bad substitution

What am I missing?

Is there a more "elegant" way of building images in a Jenkinsfile given that I want to pass --build-arg during the built?

Solution

The error message is raised because ${env.VERSION} is not a valid environment variable. Double quotes should be used to make Jenkins evaluate that variable and pass the evaluated value to the sh step:

sh "docker build --tag alerta-local --build-arg ALERTA_BASE_VERSION=${env.VERSION} alerta-custom"

Answered By - kangasta
Answer Checked By - Katrina (JavaFixing Volunteer)