@qlack/qng-pubsub NPM

@qlack/qng-pubsub

Angular support: 11.0.4

Npm package of an Angular wrapper for @qlack/qpubsub

Installing

npm install --save @qlack/qng-pubsub

Usage

Provide the browser window to your module

providers: [
  {provide: Window, useValue: window}
],

Import the QNgPubSubModule

  import {QNgPubSubModule} from '@qlack/qng-pubsub';

  imports: [
    QNgPubSubModule
  ],

Import the QNgPubSubService in your component

  import {QNgPubSubService} from '@qlack/qng-pubsub';

constructor(private qPubSubService: QNgPubSubService) {
  //use the qPubSubService
}

Starting the server

qPubSubService.init('server', true, ["http://localhost:8080", "https://myprod-url", "https://mypreprod-url"]);

The first argument is the name of this instance. This name does not have any practical implication other than helping you identifying the source of log messages.
The second argument is a boolean value indicating whether this instance of QPubSub is a server instance; you need to set it as 'true'.
The third argument optional is an array of strings containing the allowed origin domains to receive messages from.

Starting a client

qPubSubService.init("client1", false);

Similarly to the server instantiation, but indicating that this is a client instance with the 'false' argument.

During client initialisation, QPubSub will traverse the DOM and try to identify a listening QPubSub server. Once the server is identified, a ping-pong style of message exchange will take place to allow the client to register with the server. You need to ensure that when initialisation of the client takes place the server component is already loaded and initialised.

Security

To guarantee that only allowed domains can communicate with your QPubSub server, you may provide an allowed domains list while initialising QPubSub. The domain list is a string array, so multiple domains can be specified at once, e.g.

qPubSubService.init("server", true, ["http://localhost:8080", "https://myprod-url", "https://mypreprod-url"]);

API

`init(instaceID: string, server: boolean, allowedOrigins?: string[]): void`

Initialises the QPubSub instance.

iID A String value identifying the name of this instance. Its only purpose is to identify the source of console logging messages.
server A Boolean value indicating whether this instance is a server. Make sure you only have one server instance running.
allowedOrigins optional A String array with the domains from which communication is allowed. If not specified, you will see a warning in your Javascript console, however pub/sub will still work. You are strongly advised to never use QPubSub in production without a list of allowed domains.