Discourse a SSO provider for Wordpress


(Ankh2054) #1

Hi all,

Im looking at implementing a solution in wordpress where discourse becomes the SSO provider.
I already have 1000+ users on discourse and want to allow users to have accounts on the wordpress site.

Does anyone know whether this is possible today using exiting plugins?

thanks


(Jeff Atwood) #2

SSO provider is built in, search site settings. Not sure it’s very well documented at the moment but @sam added it a while ago.


(Ankh2054) #3

thanks Jeff,

I’ve configured discourse as the SSO provider, but unsure whether a plugin exists for Wordpress to redirect to logins to discourse.

How does one re-direct the Wordpress logins to discourse.


(Ankh2054) #4

I’ve installed WP-OAUTH in the hope that one can copy an existing provider.php file and modify to get it to work with Discourse. Copied the gitbhub one, settings are below if you any one trying something similar. Not working yet.

<?php

// start the user session for maintaining individual user states during the multi-stage authentication flow:
session_start();

# DEFINE THE OAUTH PROVIDER AND SETTINGS TO USE #
$_SESSION['WPOA']['PROVIDER'] = 'Github';
define('HTTP_UTIL', get_option('wpoa_http_util'));
define('CLIENT_ENABLED', get_option('wpoa_github_api_enabled'));
define('CLIENT_ID', get_option('wpoa_github_api_id'));
define('CLIENT_SECRET', get_option('wpoa_github_api_secret'));
define('REDIRECT_URI', rtrim(site_url(), '/') . '/');
define('SCOPE', 'user'); // PROVIDER SPECIFIC: "user" is the minimum scope required to get the user's id from Github
define('URL_AUTH', "http://meta.bommachine.co.uk/session/sso_provider?");
define('URL_TOKEN', "http://meta.bommachine.co.uk/session/access_token?");
define('URL_USER', "http://meta.bommachine.co.uk/session/user?");
# END OF DEFINE THE OAUTH PROVIDER AND SETTINGS TO USE #

// remember the user's last url so we can redirect them back to there after the login ends:
if (!$_SESSION['WPOA']['LAST_URL']) {$_SESSION['WPOA']['LAST_URL'] = strtok($_SERVER['HTTP_REFERER'], "?");}

# AUTHENTICATION FLOW #
// the oauth 2.0 authentication flow will start in this script and make several calls to the third-party authentication provider which in turn will make callbacks to this script that we continue to handle until the login completes with a success or failure:
if (!CLIENT_ENABLED) {
	$this->wpoa_end_login("This third-party authentication provider has not been enabled. Please notify the admin or try again later.");
}
elseif (!CLIENT_ID || !CLIENT_SECRET) {
	// do not proceed if id or secret is null:
	$this->wpoa_end_login("This third-party authentication provider has not been configured with an API key/secret. Please notify the admin or try again later.");
}
elseif (isset($_GET['error_description'])) {
	// do not proceed if an error was detected:
	$this->wpoa_end_login($_GET['error_description']);
}
elseif (isset($_GET['error_message'])) {
	// do not proceed if an error was detected:
	$this->wpoa_end_login($_GET['error_message']);
}
elseif (isset($_GET['code'])) {
	// post-auth phase, verify the state:
	if ($_SESSION['WPOA']['STATE'] == $_GET['state']) {
		// get an access token from the third party provider:
		get_oauth_token($this);
		// get the user's third-party identity and attempt to login/register a matching wordpress user account:
		$oauth_identity = get_oauth_identity($this);
		$this->wpoa_login_user($oauth_identity);
	}
	else {
		// possible CSRF attack, end the login with a generic message to the user and a detailed message to the admin/logs in case of abuse:
		// TODO: report detailed message to admin/logs here...
		$this->wpoa_end_login("Sorry, we couldn't log you in. Please notify the admin or try again later.");
	}
}
else {
	// pre-auth, start the auth process:
	if ((empty($_SESSION['WPOA']['EXPIRES_AT'])) || (time() > $_SESSION['WPOA']['EXPIRES_AT'])) {
		// expired token; clear the state:
		$this->wpoa_clear_login_state();
	}
	get_oauth_code($this);
}
// we shouldn't be here, but just in case...
$this->wpoa_end_login("Sorry, we couldn't log you in. The authentication flow terminated in an unexpected way. Please notify the admin or try again later.");
# END OF AUTHENTICATION FLOW #

# AUTHENTICATION FLOW HELPER FUNCTIONS #
function get_oauth_code($wpoa) {
	$params = array(
		'response_type' => 'code',
		'client_id' => CLIENT_ID,
		'scope' => SCOPE,
		'state' => uniqid('', true),
		'redirect_uri' => REDIRECT_URI,
	);
	$_SESSION['WPOA']['STATE'] = $params['state'];
	$url = URL_AUTH . http_build_query($params);
	header("Location: $url");
	exit;
}

function get_oauth_token($wpoa) {
	$params = array(
		'grant_type' => 'authorization_code',
		'client_id' => CLIENT_ID,
		'client_secret' => CLIENT_SECRET,
		'code' => $_GET['code'],
		'redirect_uri' => REDIRECT_URI,
	);
	$url_params = http_build_query($params);
	switch (strtolower(HTTP_UTIL)) {
		case 'curl':
			$url = URL_TOKEN . $url_params;
			$curl = curl_init();
			curl_setopt($curl, CURLOPT_URL, $url);
			curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
			curl_setopt($curl, CURLOPT_POST, 1);
			curl_setopt($curl, CURLOPT_POSTFIELDS, $params);
			// PROVIDER NORMALIZATION: Reddit requires sending a User-Agent header...
			// PROVIDER NORMALIZATION: Reddit requires sending the client id/secret via http basic authentication
			curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, (get_option('wpoa_http_util_verify_ssl') == 1 ? 1 : 0));
			curl_setopt($curl, CURLOPT_SSL_VERIFYHOST, (get_option('wpoa_http_util_verify_ssl') == 1 ? 2 : 0));
			$result = curl_exec($curl);
			break;
		case 'stream-context':
			$url = rtrim(URL_TOKEN, "?");
			$opts = array('http' =>
				array(
					'method'  => 'POST',
					'header'  => 'Content-type: application/x-www-form-urlencoded',
					'content' => $url_params,
				)
			);
			$context = $context  = stream_context_create($opts);
			$result = @file_get_contents($url, false, $context);
			if ($result === false) {
				$wpoa->wpoa_end_login("Sorry, we couldn't log you in. Could not retrieve access token via stream context. Please notify the admin or try again later.");
			}
			break;
	}
	// parse the result:
	parse_str($result, $result_obj); // PROVIDER SPECIFIC: Github encodes the access token result as a querystring by default
	$access_token = $result_obj['access_token']; // PROVIDER SPECIFIC: this is how Github returns the access token KEEP THIS PROTECTED!
	//$expires_in = $result_obj['expires_in']; // PROVIDER SPECIFIC: Github does not return an access token expiration!
	//$expires_at = time() + $expires_in; // PROVIDER SPECIFIC: Github does not return an access token expiration!
	// handle the result:
	if (!$access_token) {
		// malformed access token result detected:
		$wpoa->wpoa_end_login("Sorry, we couldn't log you in. Malformed access token result detected. Please notify the admin or try again later.");
	}
	else {
		$_SESSION['WPOA']['ACCESS_TOKEN'] = $access_token;
		//$_SESSION['WPOA']['EXPIRES_IN'] = $expires_in; // PROVIDER SPECIFIC: Github does not return an access token expiration!
		//$_SESSION['WPOA']['EXPIRES_AT'] = $expires_at; // PROVIDER SPECIFIC: Github does not return an access token expiration!
		return true;
	}
}

function get_oauth_identity($wpoa) {
	// here we exchange the access token for the user info...
	// set the access token param:
	$params = array(
		'access_token' => $_SESSION['WPOA']['ACCESS_TOKEN'], // PROVIDER SPECIFIC: the access token is passed to Github using this key name
	);
	$url_params = http_build_query($params);
	// perform the http request:
	switch (strtolower(HTTP_UTIL)) {
		case 'curl':
			$url = URL_USER . $url_params; // TODO: we probably want to send this using a curl_setopt...
			$curl = curl_init();
			curl_setopt($curl, CURLOPT_URL, $url);
			curl_setopt($curl, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']); // PROVIDER SPECIFIC: Github requires the useragent for all api requests
			// PROVIDER NORMALIZATION: Reddit requires that we send the access token via a bearer header...
			//curl_setopt($curl, CURLOPT_HTTPHEADER, array('x-li-format: json')); // PROVIDER SPECIFIC: I think this is only for LinkedIn...
			curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
			$result = curl_exec($curl);
			$result_obj = json_decode($result, true);
			break;
		case 'stream-context':
			$url = rtrim(URL_USER, "?");
			$opts = array('http' =>
				array(
					'method' => 'GET',
					'user_agent' => $_SERVER['HTTP_USER_AGENT'], // PROVIDER NOTE: Github requires the useragent for all api requests
					'header'  => "Authorization: token " . $_SESSION['WPOA']['ACCESS_TOKEN'],
				)
			);
			$context = $context  = stream_context_create($opts);
			$result = @file_get_contents($url, false, $context);
			if ($result === false) {
				$wpoa->wpoa_end_login("Sorry, we couldn't log you in. Could not retrieve user identity via stream context. Please notify the admin or try again later.");
			}
			$result_obj = json_decode($result, true);
			break;
	}
	// parse and return the user's oauth identity:
	$oauth_identity = array();
	$oauth_identity['provider'] = $_SESSION['WPOA']['PROVIDER'];
	$oauth_identity['id'] = $result_obj['id']; // PROVIDER SPECIFIC: this is how Github returns the user's unique id
	//$oauth_identity['email'] = $result_obj['email']; //PROVIDER SPECIFIC: this is how Github returns the email address
	if (!$oauth_identity['id']) {
		$wpoa->wpoa_end_login("Sorry, we couldn't log you in. User identity was not found. Please notify the admin or try again later.");
	}
	return $oauth_identity;
}
# END OF AUTHENTICATION FLOW HELPER FUNCTIONS #
?>

(Kevin Charleroi) #5

Is this working ? I can’t find any post about integrating discourse as a sso provider for wordpress


(Travis) #7

Looking for something similar. Can’t find much via search. I’m thinking this should probably be an official option in wp-discourse (using Discourse as the authority rather than WordPress).


(Piyush Singh) #8

Any update on this one. WP struggles to have a proper user profile. Discourse seems to be the obvious choice when using with WP.


(Erlend Sogge Heggen) #9

Using Discourse as an SSO provider is documented here:

That howto also links to a PHP script by @paxmanchris that implements Discourse as SSO provider: