ng build command not working in jenkins pipeline

Question

I'm fairly new to Jenkins. I set up a pipeline in Jenkins for an Angular 7 app. Here is my Jenkinsfile:

pipeline {
  agent any
  stages {
    stage('Checkout') {
      steps {
        echo 'Checkout master branch'
        checkout scm
        dir('webapp') {
          bat 'npm install'
        }
      }
    }
    stage('Build') {
      steps {
        echo 'Building..'
        dir('webapp') {
          bat 'npm run ng -- build --prod --baseHref=/webapp/ -optimization=true'
        }
      }
    }
    stage('Deploy') {
      steps {
        echo 'Deploying....'
        ftpPublisher paramPublish: null, masterNodeName: '', alwaysPublishFromMaster: true, continueOnError: false, failOnError: true, publishers: [
          [configName: 'mattdailey.net', verbose: true, transfers: [
            [asciiMode: false, cleanRemote: true, excludes: '', flatten: false, makeEmptyDirs: tur, noDefaultExcludes: false, patternSeparator: '[, ]+',
              remoteDirectory: "webapp", removePrefix: "webapp/dist", remoteDirectorySDF: false, sourceFiles: 'webapp/dist/**'
            ]
          ], usePromotionTimestamp: false, useWorkspaceInPromotion: false]
        ]
      }
    }
  }
  post {
    success {
      slackSend(color: '#00FF00', message: "Build Successful")
    }
    failure {
      slackSend(color: '#FF0000', message: "Build Failed")
    }
  }
}

When I create a build I get the following error:

ng "build" "--prod" "--baseHref=/webapp/" "-optimization=true"

Unknown option: '-n'    
npm ERR! code ELIFECYCLE    
npm ERR! errno 1

I'm using Jenkins 2.150.3, Angular CLI 7.3.4, NodeJS 10.15.1 in Windows 10. If I take out the '--' between ng and build the command works but it ignores the flags after a build. I think I need to add a path variable for angular cli but I'm not sure where to add it or what the right syntax would be.

Answer 1

@Andrew Lobban Fixing the optimization flag helped. I did have to keep the '--' between ng and build, otherwise it wouldn't recognize any of the flags. When I said it works I meant angular cli would do a regular build without any flags. Thanks.

Answer 2

The same problem I faced with Octopus CICD build. Below solution works for me.

1. Change in package json script like "build": "ng build --prod",
2. Run command from CICD like npm run build

Hope it help !