bootstrap.php

<?php
/**
 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 *
 * Licensed under The MIT License
 * For full copyright and license information, please see the LICENSE.txt
 * Redistributions of files must retain the above copyright notice.
 *
 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 * @link          http://cakephp.org CakePHP(tm) Project
 * @since         0.10.8
 * @license       http://www.opensource.org/licenses/mit-license.php MIT License
 */
namespace App\Config;

/**
 * Configure paths required to find CakePHP + general filepath
 * constants
 */
require __DIR__ . '/paths.php';

// Use composer to load the autoloader.
require ROOT . '/vendor/autoload.php';

/**
 * Bootstrap CakePHP.
 *
 * Does the various bits of setup that CakePHP needs to do.
 * This includes:
 *
 * - Registering the CakePHP autoloader.
 * - Setting the default application paths.
 */
require CAKE . 'bootstrap.php';

use Cake\Cache\Cache;
use Cake\Configure\Engine\PhpConfig;
use Cake\Console\ConsoleErrorHandler;
use Cake\Core\App;
use Cake\Core\Configure;
use Cake\Core\Plugin;
use Cake\Datasource\ConnectionManager;
use Cake\Error\ErrorHandler;
use Cake\Log\Log;
use Cake\Network\Email\Email;
use Cake\Network\Request;
use Cake\Routing\DispatcherFactory;
use Cake\Utility\Inflector;

/**
 * Read configuration file and inject configuration into various
 * CakePHP classes.
 *
 * By default there is only one configuration file. It is often a good
 * idea to create multiple configuration files, and separate the configuration
 * that changes from configuration that does not. This makes deployment simpler.
 */
try {
	Configure::config('default', new PhpConfig());
	Configure::load('app.php', 'default', false);
} catch (\Exception $e) {
	die('Unable to load Config/app.php. Create it by copying Config/app.default.php to Config/app.php.');
}

// Load an environment local configuration file.
// You can use this file to provide local overrides to your
// shared configuration.
//Configure::load('app_local.php', 'default');

// When debug = false the metadata cache should last
// for a very very long time, as we don't want
// to refresh the cache while users are doing requests.
if (!Configure::read('debug')) {
	Configure::write('Cache._cake_model_.duration', '+99 years');
	Configure::write('Cache._cake_core_.duration', '+99 years');
}

/**
 * Set server timezone to UTC. You can change it to another timezone of your
 * choice but using UTC makes time calculations / conversions easier.
 */
date_default_timezone_set('UTC');

/**
 * Configure the mbstring extension to use the correct encoding.
 */
mb_internal_encoding(Configure::read('App.encoding'));

/**
 * Register application error and exception handlers.
 */
$isCli = php_sapi_name() === 'cli';
if ($isCli) {
	(new ConsoleErrorHandler(Configure::consume('Error')))->register();
} else {
	(new ErrorHandler(Configure::consume('Error')))->register();
}

// Include the CLI bootstrap overrides.
if ($isCli) {
	require __DIR__ . '/bootstrap_cli.php';
}

/**
 * Set the full base url.
 * This URL is used as the base of all absolute links.
 *
 * If you define fullBaseUrl in your config file you can remove this.
 */
if (!Configure::read('App.fullBaseUrl')) {
	$s = null;
	if (env('HTTPS')) {
		$s = 's';
	}

	$httpHost = env('HTTP_HOST');
	if (isset($httpHost)) {
		Configure::write('App.fullBaseUrl', 'http' . $s . '://' . $httpHost);
	}
	unset($httpHost, $s);
}

Cache::config(Configure::consume('Cache'));
ConnectionManager::config(Configure::consume('Datasources'));
Email::configTransport(Configure::consume('EmailTransport'));
Email::config(Configure::consume('Email'));
Log::config(Configure::consume('Log'));

/**
 * Setup detectors for mobile and tablet.
 */
Request::addDetector('mobile', function($request) {
	$detector = new \Detection\MobileDetect();
	return $detector->isMobile();
});
Request::addDetector('tablet', function($request) {
	$detector = new \Detection\MobileDetect();
	return $detector->isTablet();
});

/**
 * Custom Inflector rules, can be set to correctly pluralize or singularize table, model, controller names or whatever other
 * string is passed to the inflection functions
 *
 * Inflector::rules('singular', ['rules' => [], 'irregular' => [], 'uninflected' => []]);
 * Inflector::rules('plural', ['rules' => [], 'irregular' => [], 'uninflected' => []]);
 *
 */

/**
 * Plugins need to be loaded manually, you can either load them one by one or all of them in a single call
 * Uncomment one of the lines below, as you need. make sure you read the documentation on Plugin to use more
 * advanced ways of loading plugins
 *
 * Plugin::loadAll(); // Loads all plugins at once
 * Plugin::load('DebugKit'); //Loads a single plugin named DebugKit
 *
 */

//Plugin::loadAll();

/**
 * Connect middleware/dispatcher filters.
 */

DispatcherFactory::add('Asset');
DispatcherFactory::add('Cache');
DispatcherFactory::add('Routing');
DispatcherFactory::add('ControllerFactory');

Plugin::load('PluginName', ['bootstrap' => true, 'routes' => false]);

composer.json

{
	"name": "cakephp/app",
	"description": "CakePHP skeleton app",
	"homepage": "http://cakephp.org",
	"type": "project",
	"license": "MIT",
	"require": {
		"php": ">=5.4.19",
		"cakephp/cakephp": "dev-3.0-plugin-bake",
		"mobiledetect/mobiledetectlib": "2.*"
	},
	"require-dev": {
		"d11wtq/boris": "1.0.*"
	},
	"suggest": {
		"phpunit/phpunit": "Allows automated tests to be run without system-wide install."
	},
	"autoload": {
		"psr-4": {
			"App\\": "App",
			"App\\Test\\": "Test",
			"": "./Plugin"
		}
	},
	"scripts": {
		"post-install-cmd": "App\\Console\\Installer::postInstall"
	}
}

plugin_layout_default.ctp

<!-- Part of Plugin/PluginName/src/Template/Layout/default.ctp -->
<body>
	<div id="wrapper">
		<?= $this->cell('PluginName.TestCell'); ?>
        </div>
</body>

plugin_pbootstrap.php

<?php
//PluginName bootstrap file

use Cake\Configure\Engine\PhpConfig;
use Cake\Core\Configure;
use Cake\Core\App;

Configure::write('App.paths.templates', array_merge(
	App::path('Template', 'PluginName'),
	Configure::read('App.paths.templates')
));