npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

postie-mediator

v1.1.0

Published

A module for handling in-process messages (commands, queries and events) within an app.

Downloads

4

Readme

Postie

Build Status

A module for handling in-process messages (commands, queries and events) within an app.

Installation

npm install postie-mediator

Importing into your project

Postie's constructor is the default export of its module, which means that importing it via CommonJS differs slightly from the norm:

const Postie = require("postie-mediator").default;

Importing via ES6 syntax:

import Postie from 'postie-mediator';

Working with Postie

Postie's API is rather simple with just two methods. See below for usage details.

Registering message handlers

To register message handlers, simply provide the constructor function of the desired message type and one or more handlers that implement the message handler interface, or a factory that produces handlers:

interface MessageHandler {
  handle(message);
}

// Greet command
class Greet {
  constructor(name){
    this.name = name;
  }
}

// Command handler (can also be an object that implements the MessageHandler interface)
class Greeter {
  handle(message){
    console.log(message.name);
  }
}

const postie = new Postie();

// Standard argument passing
postie.register(Greet, new Greeter());

// or handlers in an array
postie.register(Greet, [ new Greeter() ]);

// or a handler factory
postie.register(Greet, () => new Greeter());

Sending a message

To send a message, create an instance of a previously registered message type and dispatch it to Postie. When sending a message, a promise is returned to account for async. work within handlers; it resolves to an array of handler responses.

class Message {}

const handler = {
  handle(message) {
    return 'Message handled';
  }
};

postie.register(Message, handler);

const message = new Message();

const continuation = postie.send(message);

continuation.then(responses => // responses => [ 'Message handled' ]);

You're not a puppet

Using this module should allow you to work in whichever way you wish, without a prescribed methodology pulling on your strings. For example, while it makes sense for a command/query to only be processed by a single handler, you are free to register as many handlers as you wish for each message type.

The same goes for events too: typically they are the only type of message that can have multiple handlers. While publishing an event is more semantic than sending an event, a publish method would only be an alias for the send method, hence its omission from the API.