modx-patcher-plugin.php

//<?php
/*
 * Patcher
 * MODx plugin that adds check boxes in the administration to apply .patch
 * files to MODx core.
 *
 * Requirements
 * ============
 * - MODx 0.9.6
 * - UNIX system with `mv` and `patch`
 * - ability to `exec()` in PHP
 * - patch files in the unified diff format
 *
 * Installation
 * ============
 * - Create a new plugin with this file. And check the following event hooks:
 *     - OnMiscSettingsRender
 *     - OnManagerPageInit
 * - Create the `assets/plugins/patcher` folder.
 * - Place .patch files in unified diff format in this folder.
 * - Under Misc Settings in MODx's configuration there will be checkboxes
 *   for every patch file you added.
 *   Once checked, they are applied and renamed `.patch.applied`.
 *
 *
 * Licence
 * ======
 * Copyright Sunny Ripert <http://sunfox.org>
 * Cosmic Communication <http://agencecosmic.com>
 * Under the WTFPL <http://sam.zoy.org/wtfpl/>
 *
 */

if (!defined('PATCHER_DIRECTORY')) {
	define('PATCHER_RELATIVE_DIRECTORY', 'assets/plugins/patcher'); // no trailing slash
	define('PATCHER_DIRECTORY', '../'.PATCHER_RELATIVE_DIRECTORY); // no trailing slash
	define('PATCHER_LOG_FILE', '/logs/patcher.log');


	// Returns an array of patches with the patch id as key
	// and an array of the before/after patch states as values:
	//   0: previous state from the filename (if the file ends with .applied)
	//   1: current state from the database
	//
	// Example:
	//   patcher_get_patches() # => array('continue-save'=>array(0,0), 'edit-mode'=>array(1,1));
	function patcher_get_patches() {
		global $modx;

		$patches = array();

		$files = array_merge(glob(PATCHER_DIRECTORY . '/*.patch.applied'),
		                     glob(PATCHER_DIRECTORY . '/*.patch'));

		foreach ($files as $file) {
			$id = preg_replace('/\.patch(\.applied)?$/', '', basename($file));

			// previous state from filename
			$previous = preg_match('/\.applied$/', $file) ? 1 : 0;

			// current state from database
			$current = isset($modx->config["patcher_$id"]) ? $modx->config["patcher_$id"] : 0;

			$patches[$id] = array((int) $previous, (int) $current);
		}

		return $patches;
	}

	function patcher_apply_patch($id, $reverse = false) {
		$patch = PATCHER_RELATIVE_DIRECTORY.'/'.$id.'.patch';
		if (patcher_exec("patch -d .. -p1 -i '$patch' 2>&1"))
			patcher_exec("mv '../$patch' '../$patch.applied' 2>&1");
	}

	function patcher_reverse_patch($id) {
		$patch = PATCHER_RELATIVE_DIRECTORY.'/'.$id.'.patch';
		if (patcher_exec("patch -R -d .. -p1 -i '$patch.applied'"))
			patcher_exec("mv '../$patch.applied' '../$patch'");
	}

	function patcher_exec($cmd) {
		patcher_log("$ ".$cmd);
		$return = exec($cmd, $out, $err_code);
		if ($return)
			patcher_log($return);
		return $err_code == 0;
	}

	function patcher_log($txt) {
		$fp = fopen(PATCHER_LOG_FILE, 'a');
		fwrite($fp, $txt."\n");
		fclose($fp);
		return $txt;

		global $modx;
		$modx->l($txt."\n", 'patcher.log');
		return $txt;
	}


}

// Handle event
$e = &$modx->Event;
switch ($e->name) {

	// Settings page render
	case 'OnMiscSettingsRender':

		// Print html of the settings
		$html = '
			<table cellspacing="0" cellpadding="3" border="0" style="width:100%" class="cosmic_settings">
				<tr class="row1">
					<td class="warning" style="width:25%">Apply patches:</td>
					<td>
						<ul>';

		foreach (patcher_get_patches() as $id => $values) {
			$no =  $values[0] == 0 ? ' checked="checked"' : '';
			$yes = $values[0] == 1 ? ' checked="checked"' : '';
			$html .= '
							<li style="list-style-type:none;list-style-image:none;">
								<label style="font-weight:bold">
									<input type="radio" value="0"'.$no.'
										name="patcher_'.htmlspecialchars($id).'">
									no
								</label>
								<label style="font-weight:bold">
									<input type="radio" value="1"'.$yes.'
										name="patcher_'.htmlspecialchars($id).'">
									yes
								</label>
								'.htmlspecialchars($id).'
							</li>';
		}

		$html .= '
						</ul>
					</td>
				</tr>
				<tr>
					<td colspan="2">
						<div class="split"/>
					</td>
				</tr>
			</table>';

		$e->output($html);
	break;

	// Apply or remove the patches with "pending" state
	case 'OnManagerPageInit':

		foreach (patcher_get_patches() as $id => $values) {
			list($previous, $current) = $values;

			if ($current == 1 and $previous == 0)
				patcher_apply_patch($id);
			elseif ($current == 0 and $previous == 1)
				patcher_reverse_patch($id);
		}

	default :
		return; // stop here - this is very important.
	break;
}