PHP GitHub webhook package

Overview

This package contains classes that allow keeping up to date git repository by performing git pull on every git push to your GitHub repository. To achieve this you have to add simple script to your git repository and configure webhook on your GitHub repository.

Webhook script

For a webhook script to work you have to do 3 things:

1. Add this package to your composer dependencies
2. Add a simple PHP script that will actually handle calls to webhook
3. Configure your GitHub repository webhook to be called every time commits are pushed to GitHub

Composer

To add dependency, simply edit your composer.json and add to your require block following dependency - "dintel/php-github-webhook": "0.1.*". This is the simplest way to bring php-github-webhook libraries into your project.

Webhook script

To actually handle webhook calls, you have to add PHP script that will be accessible publicly and it will run git pull every time GitHub calls it. A simplest example of such webhook script:

<?php
require(__DIR__ . "/vendor/autoload.php");

use GitHubWebhook\Handler;

$handler = new Handler("<your secret>");
if($handler->handle()) {
    echo "OK";
} else {
    echo "Wrong secret";
}

In the script above <your secret> should be some random string you choose and it should be later supplied to GitHub when defining webhook. For more information about secrets and how they are used in GitHub webhook read Webhooks | GitHub API.

NOTE: Since this script has sensitive data in it (secret that is used to validate requests), it is advised to not put that script under git control by excluding it in .gitignore file. Another option is to take secret from some environment variable that would be defined by other means (like SetEnv in apache configuration).

GitHub repository configuration

To set up a repository webhook on GitHub, head over to the Settings page of your repository, and click on Webhooks & services. After that, click on Add webhook.

Fill in following values in form:

• Payload URL - Enter full URL to your webhook script
• Content type - should be "application/json"
• Secret - same secret you pass to constructor of Handler object
• Webhook should receive only push events and of course be active

Click Add webhook button and that's it.

Classes

Handler

Handler class actually handles webhook calls. It first checks GitHub signature and then executes git pull if signature and secret match.

Here is a complete list of methods:

• __construct($secret, $gitDir, $remote = null) - Constructor. Constructs new webhook handler that will verify that requests coming to it are signed with $secret. $gitDir must be set to path to git repo that must be updated. Optional $remote specifies which remote should be pulled.
• getData() - Getter. After successful validation returns parsed array of data in payload. Otherwise returns null.
• getDelivery() - Getter. After successful validation returns unique delivery number coming from GitHub. Otherwise returns null.
• getEvent - Getter. After successful validation returns name of event that triggered this webhook. Otherwise returns null.
• getGitDir() - Getter. Returns $gitDir that was passed to constructor.
• getGitOutput - Getter. After successful validation returns output of git as array of lines. Otherwise returns null.
• getRemote() - Getter. Returns $remote that was passed to constructor.
• getSecret() - Getter. Returns $secret that was passed to constructor.
• handle() - Handle the request. Validates that incoming request is signed correctly with $secret and executes git pull upon successful validation. Returns true on succes or false if validation failed.
• validate() - Validate request only. Returns boolean that indicates whether the request is correctly signed by $secret.