Edit

JSON

If you want to use the --json flag to return JSON output to the user, then you can set the enableJsonFlag property on the Command class.

When this property is set and the user supplies the --json flag, the command will supress all console logs and instead log the return value to the console in JSON format

import {Command} from '@oclif/core'
export class HelloCommand extends Command {
  private static enableJsonFlag = true
  public async run(): Promise<{ message: string }> {
    console.log('hello, world!')
    return { message: 'hello, world!' }
  }
}

$ my-cli hello
hello, world!

$ my-cli hello --json
{
  "message": "hello, world!"
}