With all the dependencies installed and ready to go, we can start out by adding our index.php and doing the basic bootstrap.

Create a index.php file inside your /beersample-php directory and add the following. We'll discuss it afterwards:

<?php
use Symfony\Component\HttpFoundation\Request;
use Silex\Application;
use Silex\Provider\TwigServiceProvider;

// Config Settings
define("SILEX_DEBUG", true);
define("COUCHBASE_HOSTS", "127.0.0.1");
define("COUCHBASE_BUCKET", "beer-sample");
define("COUCHBASE_PASSWORD", "");
define("COUCHBASE_CONN_PERSIST", true);
define("INDEX_DISPLAY_LIMIT", 20);

// Autoloader
require_once __DIR__.'/vendor/autoload.php';

// Silex-Application Bootstrap
$app = new Application();
$app['debug'] = SILEX_DEBUG;

// Connecting to Couchbase
$cb = new Couchbase(COUCHBASE_HOSTS, "beer-sample", COUCHBASE_PASSWORD, COUCHBASE_BUCKET, COUCHBASE_CONN_PERSIST);

// Register the Template Engine
$app->register(new TwigServiceProvider(), array('twig.path' => __DIR__.'/templates'));

// Run the Application
$app->run();
?>

The first part defines some constants to make config settings easy to change. Of course this is not needed, but makes it easy for you to change the configuration later in different environments. Afterwards, the composer autoloader is included. This is needed to make sure the use statements are available to us without having to require all PHP files by hand.

The new Application(); initializes a new Silex application. To make sure that we see all errors during development, we can set debug to true.

Now it gets interesting. We connect to our Couchbase cluster by constructing a new Couchbase object. We pass in all required information (easy to grasp with the name of the constants). This object will then be passed into all controller actions and used from there.

Because we're using the Twig template engine, we can register a TwigServiceProvider which helps us to automatially locate and load them. You'll see later how these are renderd and how we can pass data to them.

Finally, we run the application through $app->run();. The actual actions are implemented between the Twig registration call ( $app->register(new TwigServiceProvider()...) and the final run method ( $app->run()), so remeber to put them in there.

If you now run the application in your browser, you should see the following Exception showing up: "Sorry, the page you are looking for could not be found.". This is actually great, because Silex is at work, but can't find the route for the / URL. Let's fix this now. Add the following snippet between the TwigServiceProvider and the run() call:

$app->get('/', function() use ($app) {
    return $app['twig']->render('welcome.twig.html');
});

This action is called when a GET request comes in for the / URL. We don't need to fetch any data from Couchbase here, so we just instruct Silex to render a Twig template named welcome.twig.html. Since we haven't created it yet, go ahead and place the file inside the "templates" directory:

{% extends "layout.twig.html" %}

{% block content %}
    <div class="span6">
      <div class="span12">
        <h4>Browse all Beers</h4>
        <a href="/beersample-php/beers" class="btn btn-warning">Show me all beers</a>
        <hr />
      </div>
      <div class="span12">
        <h4>Browse all Breweries</h4>
        <a href="/beersample-php/breweries" class="btn btn-info">Take me to the breweries</a>
      </div>
    </div>
    <div class="span6">
      <div class="span12">
        <h4>About this App</h4>
        <p>Welcome to Couchbase!</p>
        <p>This application helps you to get started on application
            development with Couchbase. It shows how to create, update and
            delete documents and how to work with JSON documents.</p>
        <p>The official tutorial can be found
            <a href="http://www.couchbase.com/docs/couchbase-sdk-php-1.1/tutorial.html">here</a>!</p>
      </div>
    </div>
{% endblock %}

There is nothing fancy here, we're just showing some basic information to the user and guiding them to the real application functionality. Also, note the {% extends "layout.twig.html" %} and {% block content %} twig elements on top of the page.

Since we don't want to repeat the HTML layout part on every template, we can define a layout and each template is a block that is loaded into that template. Since we haven't created the layout.twig.html, do that in the same directory as the welcome.twig.html:

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>Couchbase PHP Beer-Sample</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="The Couchbase PHP Beer-Sample App">
    <meta name="author" content="Couchbase, Inc. 2012">

    <link href="/beersample-php/assets/css/bootstrap.min.css" rel="stylesheet">
    <link href="/beersample-php/assets/css/beersample.css" rel="stylesheet">
    <link href="/beersample-php/assets/css/bootstrap-responsive.min.css" rel="stylesheet">

    <!-- HTML5 shim, for IE6-8 support of HTML5 elements -->
    <!--[if lt IE 9]>
      <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script>
    <![endif]-->
  </head>
  <body>
    <div class="container-narrow">
      <div class="masthead">
        <ul class="nav nav-pills pull-right">
          <li><a href="/beersample-php">Home</a></li>
          <li><a href="/beersample-php/beers">Beers</a></li>
          <li><a href="/beersample-php/breweries">Breweries</a></li>
        </ul>
        <h2 class="muted">Couchbase Beer-Sample</h2>
      </div>
      <hr>
      <div class="row-fluid">
        <div class="span12">
            {% block content %}{% endblock %}
        </div>
      </div>
      <hr>
      <div class="footer">
        <p>&copy; Couchbase, Inc. 2012</p>
      </div>
    </div>
    <script src="/beersample-php/assets/js/jquery.min.js"></script>
    <script src="/beersample-php/assets/js/bootstrap.min.js"></script>
    <script src="/beersample-php/assets/js/beersample.js"></script>
  </body>
</html>

The {% block content %}{% endblock %} is responsible for loading the appropriate block later (the other markup is again just HTML boilerplate to help with a nice layout for Twitter Bootstrap).

If you load the page, you should see the welcome page loading! If not, you may need to look at your webserver logs to see what kind of error messages have been generated when running the scripts. Assuming all is working well, we're now ready to implement the actual functionality.