PHP Cookbook

17.7. Looking Up Addresses with LDAP

Problem

You want to query an LDAP server for address information.

Solution

Use PHP’s LDAP extension:

$ds = ldap_connect('ldap.example.com')                 or die($php_errormsg);
ldap_bind($ds)                                         or die($php_errormsg);
$sr = ldap_search($ds, 'o=Example Inc., c=US', 'sn=*') or die($php_errormsg);
$e  = ldap_get_entries($ds, $sr)                       or die($php_errormsg);

for ($i=0; $i < $e['count']; $i++) {
    echo $info[$i]['cn'][0] . ' (' . $info[$i]['mail'][0] . ')<br>';
}

ldap_close($ds)                                        or die($php_errormsg);

Discussion

LDAP stands for Lightweight Directory Access Protocol. An LDAP server stores directory information, such as names and addresses, and allows you to query it for results. In many ways, it’s like a database, except that it’s optimized for storing information about people.

In addition, instead of the flat structure provided by a database, an LDAP server allows you to organize people in a hierarchical fashion. For example, employees may be divided into marketing, technical, and operations divisions, or they can be split regionally into North America, Europe, and Asia. This makes it easy to find all employees of a particular subset of a company.

When using LDAP, the address repository is called as a data source. Each entry in the repository has a globally unique identifier, known as a distinguished name. The distinguished name includes both a person’s name, but also their company information. For instance, John Q. Smith, who works at Example Inc., a U.S. company has a ...