firebase not found in envirorment.ts file angular

// When you run ng build –prod angular-cli will use the environment.prod.ts file

// and your environment.prod.ts files environment variable doesn’t have the firebase

// field hence you are getting the exception.

export const environment = {

  production: true,

  firebase: {

    apiKey: “…”,

    authDomain: “project.firebaseapp.com”,

    databaseURL: “https://project.firebaseio.com”,

    projectId: “project”,

    storageBucket: “project.appspot.com”,

    messagingSenderId: “…”

  }

};