Example of nested commands for sywac/sywac#21

issue21-schedule-delivery.js

module.exports = {
  flags: 'schedule-delivery',
  desc: 'Launch scheduled mail delivery, max of three days in advance.',
  setup: sywac => {
    sywac
      .showHelpByDefault(false) // disable this here since schedule-delivery is a runnable command
      .option('-l, --email-list <email-list>', {
        type: 'string',
        desc: 'The mailgun email list you would like to use.',
        strinct: true, // this is misspelled, and strict does not apply to strings; use `required: true` to require this option
        defaultValue: 'something'
      })
      .option('-b, --email-body-file <email-body-file>', {
        type: 'file',
        desc: 'File containing the html for the body of the email. Relative to the emailBodyFileDir directory you set in the configuration.',
        strinct: true // this is misspelled, and strict does not apply to files; use `mustExist: true` to guarantee the path given exists on the local filesystem and is a file.
      })
      .option('-f, --from <sent-from-for-replies>', {
        type: 'string',
        desc: 'The value that the receiver will see that your emails appear to be sent from, in the form of "Kim <services@binarymist.net>"',
        strict: true // strict does not apply to strings; use `required: true` to require this option
      })
      .option('-s, --subject <subject-for-email>', {
        type: 'string',
        desc: 'The subject for the email',
        strict: true // strict does not apply to strings; use `required: true` to require this option
      })
      .option('-t, --schedule-time <time-to-schedule-email-send-for>', {
        type: 'mailgunDateTimeFormat', // since this custom type was registered at the top-level, it is safe to use everywhere in this app and does not need to be re-registered anywhere
        desc: 'The time that all emails will be sent (in RFC 2822 time).',
        strict: true // this will guarantee the validateValue method for the custom type is called
      })
      .option('-tm, --test-mode', { // -tm is not valid, flags with more than one character must use double-hyphen on the command line; otherwise -tm is parsed as -t and -m
        type: 'boolean',
        desc: 'Whether or not to send in test mode "o:testmode".',
        strict: true, // strict does not apply to booleans
        defaultValue: false
      })
      .command('list', { // could potentially replace the -o flag with a positional arg by using 'list [order=asc]' here, in which case you could remove the setup handler entirely
        desc: 'List members in order based on latest or oldest mailgunMateScheduledSends datetimes.',
        paramsDesc: 'The order to list the items in: "des" for descending, "asc" for ascending.',
        setup: sywac => { // shadowing the existing sywac variable can lead to bugs and is thus discouraged
          sywac
            // no need to redefine this option since it is inherited from the parent command's configuration
            // .option('-l, --email-list <email-list>', {
            //   type: 'string',
            //   desc: 'The mailgun email list you would like to use.',
            //   strinct: true,
            //   defaultValue: 'something'
            // })
            .option('-o, --order [des|asc(default)]', {
              type: 'string', // consider using 'enum' here and define a `choices` property as an array with all valid values
              desc: 'The order you would like the items displayed in.',
              defaultValue: 'asc'
            })
        },
        run: async (parsedArgv, context) => {
          // if this is called, then the run handler for schedule-delivery will not be called
          // this artificial delay just demonstrates that it will be awaited
          await new Promise(resolve => {
            setTimeout(() => {
              console.log('list:', parsedArgv)
              resolve()
            }, 500)
          })
        }
      })
  },
  run: (parsedArgv, context) => {
    // this will not be called if any subcommands are run
    console.log('schedule-delivery:', parsedArgv)
  }
}

issue21.js

const moment = require('moment')
const Type = require('sywac/types/type')

const internals = {}
class mailgunDateTimeFormat extends Type {
  get datatype () {
    return 'mailgunDateTimeFormat'
  }

  // this is superfluous
  // setValue (context, value) {
  //   context.assignValue(this.id, value)
  // }

  validateValue (value) {
    // https://momentjs.com/docs/#/parsing/string-format/
    const scheduledTime = moment(value, 'YYYY-MM-DD')
    internals.scheduleDateIsValid = scheduledTime.isValid()
    if (!internals.scheduleDateIsValid) return false
    internals.scheduleDateIsBeforeDeadline = scheduledTime.isBefore(moment().add(3, 'days'))
    if (!internals.scheduleDateIsBeforeDeadline) return false
    internals.scheduleDateIsAfterNow = scheduledTime.isAfter(moment())
    if (!internals.scheduleDateIsAfterNow) return false

    internals.scheduledSendDateTime = value
    return true
  }

  buildInvalidMessage (context, msgAndArgs) {
    super.buildInvalidMessage(context, msgAndArgs)
    let customMessage

    if (!internals.scheduleDateIsValid) customMessage = `The datetime you entered was not valid according to mailgun\'s rules. RFC 2822, formatted as mailgun requires "YYYY-MM-DD", See (https://documentation.mailgun.com/en/latest/user_manual.html#scheduling-delivery) for more information.`
    else if (!internals.scheduleDateIsBeforeDeadline) customMessage = `The datetime you entered was outside of the mailgun 3 days schedule linmmit.`
    else if (!internals.scheduleDateIsAfterNow) customMessage = `The datetime you entered was in the past.`

    msgAndArgs.msg += ` Please specify a valid schedule datetime. ${customMessage} Please try again.`
  }
}

require('sywac')
  .registerFactory('mailgunDateTimeFormat', opts => new mailgunDateTimeFormat(opts))
  .command(require('./issue21-schedule-delivery'))
  .help('-h, --help')
  .showHelpByDefault() // this is fine here and can be disabled at lower levels (commands) if necessary
  .parseAndExit() // this initiates parsing of process.argv and will exit the process if any parsing/validation errors occur