jerni
a framework to build data-driven products from the ground up

module: jerni/lib/mapEvents

utility function to map an event type to a event handler

Summary

type: Function

Parameters

handlersMap
: Record<eventName:string,handler:(UncommittedEvent) => Operation|Operation[]>

an object with keys are event types and values are projection functions

returns

(UncommittedEvent) => Operation[]

Usages

// utility function to map an event type to a event handler
const mapEvents = require("jerni/lib/mapEvents");
const transform = mapEvents({
  USER_REGISTERED(event) {
    return {
      insertOne: {
        id: event.payload.id,
        username: event.payload.username,
        createdAt: event.payload.registered_timstamp,
        active: true,
      },
    };
  }
  USER_SUSPENDED(event) {
    return {
      updateOne: {
        where: { id: event.payload.user_id },
        changes: {
          $set: { active: false },
        },
      },
    };
  },
});