gepard/gepard-php

PHP client for gepard:General purpose communications for distributed applications / Microservices / events, semaphores and messages for JavaScript, Java, Python and PHP

gepard-php

General purpose communication and synchronization layer for distributed applications / Microservices / events, semaphores, locks and messages for JavaScript, Java, Python and PHP, _(*1)

• Overview
• Install
• Usecases
  • Updating a Customer-record in the Database

Overview

This PHP module implements a simple client for the GEPARD middleware for general purpose distributed applications., _(*2)

In order to use this PHP client you must have installed the GEPARD middleware. This is simply done by executing the command:, _(*3)

    npm install gepard

Prerequisite for this command is the installation of node and npm. For more information see gepard on npm and gessinger-hj/gepard on github., _(*4)

If you are interested in the python client see gepard-python on pypi and gepard-python on github, _(*5)

Install

If you not yet have a composer.json create this file with the following content:, _(*6)

{
    "require": {
        "gepard/gepard-php": ">=1.0"
    },
    "minimum-stability": "dev" 
}

If this composer.json file already exists in your project-directory add the body-lines above. After this is done execute the command:, _(*7)

composer install

Usecases

Updating a Customer-record in the Database

Suppose there is a database containing customer base-data like for example name, id, enabled,..., _(*8)

The access to the database for example is done with laravel/eloquent. The UPDATE is coded with the following code-snippet:, _(*9)

$customer_Id = 1 ;
$customer = App\Customer::find($customer_id);

$customer->name = 'New Customer Name';

$customer->save();

Interested 3rd parties now are informed by sending an Event:, _(*10)

Client::getInstance()->emit('CUSTOMER_CHANGED', ['CUSTOMER_ID' => $customer_id]);

Interested parties for example are:, _(*11)

• A Java program which sends an e-mail., _(*12)

  Client.getInstance().on ( new String[] { "CUSTOMER_CHANGED" }, (e) -> {
      Integer customer_id = e.getValue ( "CUSTOMER_ID" ) ;
  
      *select customer from database with customer_id*
      *use any mail-api to send mail*
  } ) ;
  

• A JavaScript program which sends an e-mail:, _(*13)

  gepard.getClient().on ( 'CUSTOMER_CHANGED', (e) => {
      let customer_id = e.getValue ( 'CUSTOMER_ID' ) ;
  
      *select customer from database with customer_id*
      *use any mail-api to send mail*
  } ) ;
  

• A Python program which sends an e-mail:, _(*14)

  
  def on_CUSTOMER_CHANGED ( event ):
      customer_id = event.getValue ( 'CUSTOMER_ID' ) ;
  
      *select customer from database with customer_id*
      *use any mail-api to send mail*
  
  gepard.Client.getInstance().on ( 'CUSTOMER_CHANGED', on_CUSTOMER_CHANGED ) ;
  

• A single page web-app or a React-native app, _(*15)

  gepard.getWebClient().on ( 'CUSTOMER_CHANGED', (e) => {
      let customer_id = e.getValue ( 'CUSTOMER_ID' ) ;
  
      if ( customer-data are displayed in any part of the page ) {
          *select customer from database with customer_id via a REST call*
          *update appropriate display*
      }
  } ) ;