Application Building With Horde

Chuck Hagenbuch

The Horde Project

You probably know that Horde does webmail. But Horde also provides a framework for building applications. Chuck Hagenbuch will demonstrate a mix of ORM, prototype +, and mapping APIs that quickly assemble into an application using Horde (call it a mashup if you must). We'll also demonstrate building standalone pages that incorporate content from an existing Horde installation.

Chuck Hagenbuch founded the Horde Project in 1998 and has been working with PHP and the world of web development ever since. He is currently an independent consultant, and has provided professional services to high-profile PHP users such as PayPal and Portugal Telecom.

Syllabus: Horde

"What is Horde?"

Why: Libraries

Why: Standards

Why: Backend Independence

Why: Applications

Why: Internationalization

Why: The Project

Building Your Own

In which the intrepid audience gets l33t

Where to start?

With a skeleton!

Horde Skeleton

Everything you need to write a standard Horde application

What if you want something like this?

Property Tracking Tutorial

Tools used

Why, Continued

PHP 5 and the future of Horde

Introducing RDO

RDO Example Usage

$um = new UserMapper();

$userCount = $um->count(); // Count all users.

$exists = $um->exists(1); // Check if id 1 exists.

// Look for Alice
$user = $um->find(Horde_RDO::FIND_FIRST,
                     array('name' => 'Alice'));
if ($user) {
    echo "Found Alice: id $user->id\n";
} else {
    // Create a new user.

RDO: Creating & Editing

$user = $um->create(array(
    'name' => 'Alice',
    'phone' => '212-555-6565'));
echo "Created new user with id: {$user->id}\n";

// Change the name of the user and save.
$user->name = 'Bob';

RDO: More Find & Delete

// List all users.
echo "Looking for all:\n";
foreach ($um->find(Horde_RDO::FIND_ALL) as $user) {
    echo "  (" . $user->id
        . ") " . $user->name . "\n";

// Fetch id 2 and delete.
$user = $um->find(2);

Form Generation

$vars = Variables::getDefaultVariables();
$form = new Horde_Form_Helper($mapper, $vars,
                              'My Form Title');
$form->renderActive(); // Edit form
$form->delete(); // process a delete action
$form->update(); // process an update form
$form->create(); // process a create form


Motivation: How many times do I have to loop through this #*)&%% array?

$data = array();
while ($row = mysql_fetch_array()) {
    $data[] = $row;

foreach ($data as $index => $row) {
    $data[$index]['foo'] = format_somehow($row['foo']);

foreach ($data as $row) {
    echo '<p>' . display($row) . '</p>';

Remember Flyweight?

Flyweight is a software design pattern. When many objects must be manipulated and these cannot afford to have extraneous data, flyweight is appropriate.

In the flyweight pattern, the data has no pointers to the data type methods, because these would consume too much space. Instead, the subroutines are called directly. In some cases, flyweight inheritance is performed by "shift-in" and "shift-out" data markers as a higher-level operation cycles through an array of flyweight data.

One classic example of a flyweight pattern are the characters stored in a word processor. Each character represents an object that has a font face, font size, and other formatting data. As you can imagine, a large document with this data structure would bloat the memory footprint of the word processor. Moreover, since much of this data is repeated, there must be a way to reduce the footprint - the Flyweight pattern. Each of the character objects would contain a reference to a separate formatting object which contains the required properties. This greatly reduces the memory footprint by combining all of the like-formatted characters into simpler objects that reference a single formatting object.

Lens use

$items = $mapper->find(Horde_RDO::FIND_ALL);
$formattedItems = new Horde_RDO_Decorating_Iterator(
    $items, new Horde_RDO_Lens());

echo '<ul>';
foreach ($formattedItems as $item) {
     echo '<li>' . $item->name
         . ' :' . $item->desc . '</li>';
echo '</ul>';

Lens Implementation

A Package Tracking Application

Package Tracking: Delivery Tracking

Package Tracking Code

The Code

Drop the config/registry.d-packages.php file into your horde/config/registry.d/ directory with any appropriate changes, and use with Horde from CVS (3.2-CVS).

Doing more with our data

Let's provide a different way to see the packages we're expecting. How about WebDAV?

WebDAV browsing made simple

Obrowser, where art thou?

Alternate ways to see what WebDAV sees:

Implementing /browse

External use of Horde data

Setup Code

@define('AUTH_HANDLER', true);
Tell Horde not to throw someone to a login screen; you'll handle authentication.
$session_control = 'none';
Don't use sessions
require_once '/var/www/horde/lib/base.php';
Load a base Horde environment

Getting Block Content

require_once 'Horde/Block/Collection.php';
$weather = Horde_Block_Collection::getBlock(
    array('location' => 'Boston, MA',
          'days' => 3,
          'units' => 'standard'));

Showing Block Content

echo $weather->getTitle();
echo $weather->getContent();