| Current File : //opt/RZphp74/includes/doc/Net_LDAP2/doc/examples/schema_cache.php |
<?php
/**
* This is a short example on how to use the schema cache facility.
* Schema caching allows you to store the fetched schema on disk
* (or wherever you want, depending on the cache class used) so
* initialisation of Net_LDAP2 becomes a little faster.
*
* Two examples will be showed here:
* 1. how to use the packaged file based cache
* 2. how to write a custom cache class
*/
// Class includes; this assumes Net_LDAP2 installed in PHPs include path
// or under subfolder "Net" in the local directory.
require_once 'Net/LDAP2.php';
// Configuration
// host can be a single server (string) or multiple ones - if we define more
// servers here (array), we can implement a basic fail over scenario.
// If no credentials (binddn and bindpw) are given, Net_LDAP2 establishes
// an anonymous bind.
// See the documentation for more information on the configuration items!
$ldap_config = array(
// 'host' => 'ldap.example.org',
'host' => array('ldap1.example.org', 'ldap2.example.org'),
// 'binddn' => 'cn=admin,o=example,dc=org',
// 'bindpw' => 'your-secret-password',
'tls' => false,
'base' => 'o=example,dc=org',
'port' => 389,
'version' => 3,
'filter' => '(cn=*)',
'scope' => 'sub'
);
/*
* EXAMPLE 1: How to use the packaged file based cach
* This cache class stores the schema object on disk once Net_LDAP2
* initially fetched it from the LDAP server. This will make Net_LDAP2
* use the disk version instead of loading the schema from LDAP
* unless the schema object becomes too old.
*/
// Configuring the schema cacher
// see the source code of SimpleFileSchemaCache.php for config options
// An interesting idea is, to store the file in some tmpfs mount, which will
// result in storing the schema cache in memory instead of disk.
$mySchemaCache_cfg = array(
'path' => '/tmp/Net_LDAP2_Schema.cache', // place to put cache file
'max_age' => 86400 // max age is 24 hours (in seconds)
);
// Initialize cache with the config
$mySchemaCache = new Net_LDAP2_SimpleFileSchemaCache($mySchemaCache_cfg);
// As usual, connect to configured ldap server
$ldap = Net_LDAP2::connect($ldap_config);
if (Net_LDAP2::isError($ldap)) {
die('BIND FAILED: '.$ldap->getMessage());
}
// and finally register our initialized cache object
$res = $ldap->registerSchemaCache($mySchemaCache);
if (Net_LDAP2::isError($res)) {
die('REGISTER CACHE FAILED: '.$res->getMessage());
}
// Here we go, Net_LDAP2 will fetch the schema once and then use the disk version.
/*
* EXAMPLE 2: How to write a custom cache class
* Writing a custom cache class is easy. You just have to wipe out a
* class that implements the SchemaCache interface.
* How a cache class must look like is documented in the interface
* definition file: SchemaCache.interface.php
* Here we will write a small hacky cache that stores the schema
* in the php session. This gives us a nice per-user cache that
* survives for the php session. This cache will obviously not
* be so performant as the SimpleFileSchemaCache but may be
* useful for other purposes.
*/
// Firstly, we need our custom schema class...
class MySessionSchemaCache implements Net_LDAP2_SchemaCache {
/**
* Initilize the cache
*
* Here we do nothing. You can use the class constructor for everything you
* want, but typically it is used to configure the caches config.
*/
public function MySessionSchemaCache () {
// nothing to see here, move along...
}
/**
* Load schema from session
*
* For the sake of simplicity we dont implement a cache aging here.
* This is not a big problem, since php sessions shouldnt last endlessly.
*
* @return Net_LDAP2_Schema|Net_LDAP2_Error|false
*/
public function loadSchema() {
// Lets see if we have a session, otherwise we cant use this cache
// and drop some error that will be returned by Net_LDAP2->schema().
// Minor errors should be indicated by returning false, so Net_LDAP2
// can continue its work. This will result in the same behavior as
// no schema cache would have been registered.
if (!isset($_SESSION)) {
return new Net_LDAP2_Error(__CLASS__.": No PHP Session initialized.".
" This cache needs an open PHP session.");
}
// Here the session is valid, so we return the stores schema.
// If we cant find the schema (because cahce is empty),w e return
// false to inidicate a minor error to Net_LDAP2.
// This causes it to fetch a fresh object from LDAP.
if (array_key_exists(__CLASS__, $_SESSION)
&& $_SESSION[__CLASS__] instanceof Net_LDAP2_SchemaCache) {
return $_SESSION[__CLASS__];
} else {
return false;
}
}
/**
* Store the schema object in session
*
* @return true|Net_LDAP2_Error
*/
public function storeSchema($schema) {
// Just dump the given object into the session
// unless in loadSchema(), it is important to only return
// Net_LDAP2_Error objects if something crucial went wrong.
// If you feel that you want to return an error object, be sure
// that you have read the comments in Net_LDAP2_SchemaCache.interface.php
// or you will seriously hurt the performance of your application!!!!
$_SESSION[__CLASS__] = $schema;
return true;
}
}
// Ok, now we have our finished cache object. Now initialize and register it
// the usual way:
$mySchemaCache = new MySessionSchemaCache();
$ldap = Net_LDAP2::connect($ldap_config);
if (Net_LDAP2::isError($ldap)) {
die('BIND FAILED: '.$ldap->getMessage());
}
$res = $ldap->registerSchemaCache($mySchemaCache);
if (Net_LDAP2::isError($res)) {
die('REGISTER CACHE FAILED: '.$res->getMessage());
}
// Now, the Schema is cached in the PHP session :)