N3H Step Builder

Help build flow step messager.

Conventions for Flow Step

• each step has a name prefixed with 'flow' and flow name, such as flow.$flow.$step
• for the entry step, subscribe the topic of its name
• for other steps, subscribe the topics it follows
• for all subscriptions, use its name as queue group name
• the topics a step emits are classified into 2 categories:
  • $name.ok(.*)?
  • $name.failed(.*)?

API

buildStep

(Options) => Void

Options ~ {
  natsEx: NatsEx,
  flowName: String,
  stepName: String,
  followStep?: String,
  validator?: (data) => data,
  handler: Handler
}

Handler ~ (data, message, receivedTopic): HandlerThis => Promise => Void

HandlerThis ~ {
  emit: {
    ok: (data?) => messageId,
    okCase: (case: String, data?) => messageId,
    failed: (data?) => messageId,
    failedCase: (case: String, data?) => messageId,
  }
}

License

MIT