hermes

Javascript messaging library

Installation

npm i @thalesrc/hermes or yarn add @thalesrc/hermes

Usage

The main concept is sending messages via MessageClient's and answering them via MessageHost's.

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Iframe

Send and recieve messages accross iframes and parent windows

// inside iframe
import { IframeMessageClient, Request } from '@thalesrc/hermes/iframe';

class MessageSenderService extends IframeMessageClient {
  @Request('hello')
  public sayHello(name: string): Observable<string> {
    return null;
  }
}

const service = new MessageSenderService();

service.sayHello('John').subscribe(message => {
  console.log(message);
});

// 'Hi John, here are some data for you'
// 'Thales Rocks!!'

// inside parent window
import { IframeMessageHost, Listen, UpcomingMessage } from '@thalesrc/hermes/iframe';
import { of } from 'rxjs';

class MessageListenerService extends IframeMessageHost {
  @Listen('hello')
  public listenHello({data, sender}: UpcomingMessage): Observable<string> {
    return of(
      'Hi ' + data + ', here is some data for you',
      'Thales Rocks!!'
    );
  }
}

const listener = new MessageListener();

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Chrome Extensions

Send and recieve messages accross tabs, background-scripts, content-scripts etc.

// content-script or a page etc.
import { ChromeMessageClient, Request } from '@thalesrc/hermes/chrome';

class MessageSenderService extends ChromeMessageClient {
  @Request('hello')
  public sayHello(name: string): Observable<string> {
    return null;
  }
}

const service = new MessageSenderService();

service.sayHello('John').subscribe(message => {
  console.log(message);
});

// 'Hi John, here are some data for you'
// 'Thales Rocks!!'

// background-script etc.
import { ChromeMessageHost, Listen } from '@thalesrc/hermes/chrome';
import { of } from 'rxjs';

class MessageListenerService extends ChromeMessageHost {
  @Listen('hello')
  public listenHello(name: string): Observable<string> {
    return of(
      'Hi ' + name + ', here is some data for you',
      'Thales Rocks!!'
    );
  }
}

const listener = new MessageListener();

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Workers

Implemented but not documented yet

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Broadcast

Implemented but not documented yet