A Sample LDAP Application in PHP Page 14

So we finally get down to putting to some practical purpose what we gleaned through the course of this chapter.

We will develop an application that will export the directory information for the employees of our favorite company Foo Widgets Inc. Let us look at what could be the possible requirements and design considerations for such an application:

• There are two categories of users - regular employees and the directory administrator.
• The application should allow a regular employee to search entries corresponding to all other employees and to modify the entry corresponding to them.
• The administrator should have exclusive priveleges unavailable to regular employees - to create new entries and delete existing entries.
• The application should use an LDAP directory as the back-end.
• It should have a simple front-end, with all complexity moved to the back-end. It should ideally be browser-independent.
• A set of common utility functions first, upon which to build the application itself.

The script below is the first that gets invoked as part of launching the application:

<?php
// empdir_first.php

We include a set of utility functions here:

require("empdir_functions.php");

This script is called again as a result of the user deciding to either add a new entry or to search for an existing entry:

if (!isset($choice)) {
    generateHTMLHeader("Click below to access the Directory");
    generateFrontPage();
} else if (strstr($choice, "ADD")) {
    $firstCallToAdd = 1;

For additions to the directory the empdir_add.php script is called:

    require("empdir_add.php");
} else {
    $firstCallToSearch = 1;

For searching the directory, we call the empdir_search.php script:

    require("empdir_search.php");
}
?>

This is how the initial screen would look to the user:

The script empdir_common.php contains some site-specific information that we need to customize to suit over environment:

<?php
//empdir_common.php

This conditional statement would ensure that this file does not get included multiple times:

//Avoid multiple include()
if (isset($EMPDIR_CMN)) {
    return;
} else {
    $EMPDIR_CMN = true;
}
//Customize these to your environment

This is the base DN of our company directory:

$baseDN = "o=Foo Widgets, c=us";

Below is the fully qualified hostname and port number of the LDAP server. We use OpenLDAP in this case - however, the code should work fine with any standard LDAP server:

$ldapServer = "www.foowid.com";
$ldapServerPort = 4321;
?>

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