A simple top-level view of a PHP cas client integration

gistfile1.php

<?php
/**
 * PHP-CAS library.
 */
require_once "CAS/CAS.php";
/**
 * d2l SSO library.
 */
require_once "d2l-login.php";
/**
 * shared API details and API path constants
 */
require_once "config.php";

// initialize phpCAS
phpCAS::client(CAS_VERSION_2_0, CAS_DOMAIN, CAS_PORT, CAS_ENDPOINT, false);

// include the a root cert for SSL verification
phpCAS::setCasServerCACert(CAS_CA_CERT);

// force CAS authentication
#if (!phpCAS::isAuthenticated()){
d2l_log("Forcing CAS auth.", $_REQUEST);
phpCAS::forceAuthentication();
#}
// at this step, the user has been authenticated by the CAS server
// and the user's login name can be read with phpCAS::getUser().

// logout if desired
if (isset($_REQUEST['logout'])) {
    d2l_log("Logging out of CAS.", $_REQUEST);
        phpCAS::logout();
}

$user = phpCAS::getUser();
d2l_log("CAS got user $user", "");

// fetch guid and log $user in
if ($guid =  generate_expiring_guid($user, $default_params)){
    d2l_log("Preparing to execute sso_login as $user", $_REQUEST);
    sso_login($user, $guid);
} else d2l_log("Failed to fetch guid for $user", $_REQUEST);

?>

gistfile2.php

<?php
/**
 * PHP-CAS library.
 */
require_once "CAS/CAS.php";
/**
 * shared API details and API path constants
 */
require_once "config.php";
/**
 * eexperience.com login funcs
 */
require_once 'experience.php';

// initialize phpCAS
phpCAS::client(SAML_VERSION_1_1, CAS_DOMAIN, CAS_PORT, CAS_ENDPOINT);

// include the a root cert for SSL verification
phpCAS::setCasServerCACert(CAS_CA_CERT);

// force CAS authentication
phpCAS::forceAuthentication();
// at this step, the user has been authenticated by the CAS server
// and the user's login name can be read with phpCAS::getUser().

// logout if desired
if (isset($_REQUEST['logout'])) {
        phpCAS::logout();
}

# get the user and the attributes
$user = phpCAS::getUser();
$user_info = phpCAS::getAttributes();

# if an alternative auth_target_url is specified, use it
$target_url = isset($_REQUEST['auth_target_url'])? $_REQUEST['auth_target_url'] : EXPERIENCE_TARGET;

# get a login URL
$url = experience_login($user, $target_url, $user_info);

header("Status: 302 Found");
header("Location: $url");
?>