How to automatically deploy from GitHub

Deploy

# Deploy your site with git

This gist assumes:

* you have an online remote repository (github / bitbucket etc.)
* you have a local git repo
* and a cloud server (Rackspace cloud / Amazon EC2 etc)
  * your (PHP) scripts are served from /var/www/html/
  * your webpages are executed by Apache
  * the Apache user is named `www-data` (may be `apache` on other systems)
  * apache's home directory is /var/www/ 

# 1 - On your local machine

*Here we add the deployment script and push it to the origin, the deployment script runs git commands to PULL from the origin thus updating your server*

## Grab a deployment script for your site

See [deploy.php](#file-deploy-php)

## Add, commit and push this to github

    git add deploy.php
    git commit -m 'Added the git deployment script'
    git push -u origin master

# 2 - On your server

*Here we install and setup git on the server, we also create an SSH key so the server can talk to the origin without using passwords etc*

## Install git...

After you've installed git, make sure it's a relatively new version - old scripts quickly become problematic as github / bitbucket / whatever will have the latests and greatest, if you don't have a recent version you'll need to figure out how to upgrade it :-)

    git --version

## Setup git (optionally)

    git config --global user.name "Server"
    git config --global user.email "server@server.com"

## Create an ssh directory for the apache user

    sudo mkdir /var/www/.ssh
    sudo chown -R apache:apache /var/www/.ssh/

## Generate a deploy key for apache user

    sudo -Hu apache ssh-keygen -t rsa # choose "no passphrase"
    sudo cat /var/www/.ssh/id_rsa.pub

# 3 - On your origin (github)

*Here we add the SSH key to the origin to allow your server to talk without passwords. In the case of GitHub we also setup a post-receive hook which will automatically call the deploy URL thus triggering a PULL request from the server to the origin*

## GitHub instructions

### Add the SSH key to your user

1. https://github.com/settings/ssh
1. Create a new key
1. Paste the deploy key you generated on the server

### Set up service hook

1. https://github.com/oodavid/server.com/admin/hooks
1. Select the **Post-Receive URL** service hook
1. Enter the URL to your deployment script - http://server.com/deploy.php
1. Click **Update Settings**

## Bitbucket instructions

### Add the SSH key to your account

1. https://bitbucket.org/account/ssh-keys/
1. Create a new key
1. Paste the deploy key you generated on the server

### Set up service hook

1. Go to: Repo > Admin > Services
1. Select "POST"
1. Add the URL to your deployment script - http://server.com/deploy.php
1. Save

# 4 - On the Server

*Here we clone the origin repo into a chmodded /var/www/html folder*

## Pull from origin

    sudo chown -R www-data:www-data /var/www/html
    sudo -Hu www-data git clone git@github.com:you/server.git /var/www/html

# Rejoice!

Now you're ready to go :-)

## Some notes

* Navigate the the deployment script to trigger a pull and see the output:
  * http://server.com/deploy.php
  * ***this is useful for debugging too ;-)***
 * When you push to GitHub your site will automatically ping the above url (and pull your code)
 * When you push to Bitbucket you will need to manually ping the above url

## Sources
 * https://gist.github.com/1809044 who in turn referenced
   * [Build auto-deploy with php and git(hub) on an EC2 Amazon AMI instance](https://gist.github.com/1105010) - who in turn referenced:
     * [ec2-webapp / INSTALL.md](https://github.com/rsms/ec2-webapp/blob/master/INSTALL.md#readme)
     * [How to deploy your code from GitHub automatically](http://writing.markchristian.org/how-to-deploy-your-code-from-github-automatic)

deploy.php

<?php

// Forked from https://gist.github.com/1809044
// Available from https://gist.github.com/nichtich/5290675#file-deploy-php

$TITLE   = 'Git Deployment Cat';
$VERSION = '1.0';
// the shared secret, used to sign the POST data (using HMAC with SHA1)
$secret = 'your secret in githubs web hook';

// receive POST data for signature calculation, don't change!
$post_data = file_get_contents('php://input');
$signature = 'sha1=' . hash_hmac('sha1', $post_data, $secret);


echo <<<EOT
<!DOCTYPE HTML>
<html lang="en-US">
<head>
        <meta charset="UTF-8">
        <title>$TITLE</title>
</head>
<body style="background-color: #000000; color: #FFFFFF; font-weight: bold; padding: 0 10px;">
<pre>
  o-o    $TITLE
 /\\"/\   v$VERSION
(`=*=')
 ^---^`-.


EOT;

$WH_SIG = $_SERVER['HTTP_X_HUB_SIGNATURE'];

if ($WH_SIG != $signature) {
	header('HTTP/1.1 403 Forbidden');
 	echo "<span style=\"color: #ff0000\">Sorry, you can't annoy this CAT!!</span>\n";
    echo "</pre>\n</body>\n</html>";
    exit;
}

flush();

// Actually run the update

$commands = array(
	'echo $PWD',
	'whoami',
	'git pull',
	'git status',
	'git submodule sync',
	'git submodule update',
	'git submodule status',
    //'test -e /usr/share/update-notifier/notify-reboot-required && echo "system restart required"',
);

$output = "\n";

$log = "####### ".date('Y-m-d H:i:s'). " #######\n";

foreach($commands AS $command){
    // Run it
    $tmp = shell_exec("$command 2>&1");
    // Output
    $output .= "<span style=\"color: #6BE234;\">\$</span> <span style=\"color: #729FCF;\">{$command}\n</span>";
    $output .= htmlentities(trim($tmp)) . "\n";

    $log  .= "\$ $command\n".trim($tmp)."\n";
}

$log .= "\n";

file_put_contents ('deploy-log.txt',$log,FILE_APPEND);

echo $output;

?>
</pre>
</body>
</html>