I am currently messing about with the Facebook Chat API. I want to send chat messages to my facebook contacts via an App.
Using the example provided by facebook I was able to connect to the facebook chat server. But that had more of an trial and error thing here. I could only vaguely understand how requests and responses are sent and received. It would be great if someone could provide further explanation or further reading.
My actual question is: How can I send messages after connecting to the chat server?
<?php
// Copyright 2004-present Facebook. All Rights Reserved.
$STREAM_XML = '<stream:stream '.
'xmlns:stream="http://etherx.jabber.org/streams" '.
'version="1.0" xmlns="jabber:client" to="chat.facebook.com" '.
'xml:lang="en" xmlns:xml="http://www.w3.org/XML/1998/namespace">';
$AUTH_XML = '<auth xmlns="urn:ietf:params:xml:ns:xmpp-sasl" '.
'mechanism="X-FACEBOOK-PLATFORM"></auth>';
$CLOSE_XML = '</stream:stream>';
$RESOURCE_XML = '<iq type="set" id="3">'.
'<bind xmlns="urn:ietf:params:xml:ns:xmpp-bind">'.
'<resource>fb_xmpp_script</resource></bind></iq>';
$SESSION_XML = '<iq type="set" id="4" to="chat.facebook.com">'.
'<session xmlns="urn:ietf:params:xml:ns:xmpp-session"/></iq>';
$START_TLS = '<starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls"/>';
function open_connection($server) {
print "[INFO] Opening connection... ";
$fp = fsockopen($server, 5222, $errno, $errstr);
if (!$fp) {
print "$errstr ($errno)<br>";
} else {
print "connnection open<br>";
}
return $fp;
}
function send_xml($fp, $xml) {
fwrite($fp, $xml);
}
function recv_xml($fp, $size=4096) {
$xml = fread($fp, $size);
if ($xml === "") {
return null;
}
// parses xml
$xml_parser = xml_parser_create();
xml_parse_into_struct($xml_parser, $xml, $val, $index);
xml_parser_free($xml_parser);
return array($val, $index);
}
function find_xmpp($fp, $tag, $value=null, &$ret=null) {
static $val = null, $index = null;
do {
if ($val === null && $index === null) {
list($val, $index) = recv_xml($fp);
if ($val === null || $index === null) {
return false;
}
}
foreach ($index as $tag_key => $tag_array) {
if ($tag_key === $tag) {
if ($value === null) {
if (isset($val[$tag_array[0]]['value'])) {
$ret = $val[$tag_array[0]]['value'];
}
return true;
}
foreach ($tag_array as $i => $pos) {
if ($val[$pos]['tag'] === $tag && isset($val[$pos]['value']) &&
$val[$pos]['value'] === $value) {
$ret = $val[$pos]['value'];
return true;
}
}
}
}
$val = $index = null;
} while (!feof($fp));
return false;
}
function xmpp_connect($options, $access_token) {
global $STREAM_XML, $AUTH_XML, $RESOURCE_XML, $SESSION_XML, $CLOSE_XML, $START_TLS;
$fp = open_connection($options['server']);
if (!$fp) {
return false;
}
print("Connection Opened <br />");
// initiates auth process (using X-FACEBOOK_PLATFORM)
send_xml($fp, $STREAM_XML);
if (!find_xmpp($fp, 'STREAM:STREAM')) {
return false;
}
print_r("XMPP Stream Found <br />");
if (!find_xmpp($fp, 'MECHANISM', 'X-FACEBOOK-PLATFORM')) {
return false;
}
print_r("XMPP Mechanism Found <br />");
// starting tls - MANDATORY TO USE OAUTH TOKEN!!!!
send_xml($fp, $START_TLS);
if (!find_xmpp($fp, 'PROCEED', null, $proceed)) {
return false;
}
print_r("XMPP Proceed Found <br />");
stream_socket_enable_crypto($fp, true, STREAM_CRYPTO_METHOD_TLS_CLIENT);
send_xml($fp, $STREAM_XML);
if (!find_xmpp($fp, 'STREAM:STREAM')) {
return false;
}
if (!find_xmpp($fp, 'MECHANISM', 'X-FACEBOOK-PLATFORM')) {
return false;
}
// gets challenge from server and decode it
send_xml($fp, $AUTH_XML);
if (!find_xmpp($fp, 'CHALLENGE', null, $challenge)) {
return false;
}
$challenge = base64_decode($challenge);
$challenge = urldecode($challenge);
parse_str($challenge, $challenge_array);
// creates the response array
$resp_array = array(
'method' => $challenge_array['method'],
'nonce' => $challenge_array['nonce'],
'access_token' => $access_token,
'api_key' => $options['app_id'],
'call_id' => 0,
'v' => '1.0',
);
// creates signature
$response = http_build_query($resp_array);
// sends the response and waits for success
$xml = '<response xmlns="urn:ietf:params:xml:ns:xmpp-sasl">'.
base64_encode($response).'</response>';
send_xml($fp, $xml);
if (!find_xmpp($fp, 'SUCCESS')) {
return false;
}
// finishes auth process
send_xml($fp, $STREAM_XML);
if (!find_xmpp($fp,'STREAM:STREAM')) {
return false;
}
if (!find_xmpp($fp, 'STREAM:FEATURES')) {
return false;
}
send_xml($fp, $RESOURCE_XML);
if (!find_xmpp($fp, 'JID')) {
return false;
}
send_xml($fp, $SESSION_XML);
if (!find_xmpp($fp, 'SESSION')) {
return false;
}
// we made it!
send_xml($fp, $CLOSE_XML);
print ("Authentication complete<br>");
fclose($fp);
return true;
}
//Gets access_token with xmpp_login permission
function get_access_token($app_id, $app_secret, $my_url){
$code = $_REQUEST["code"];
if(empty($code)) {
$dialog_url = "https://www.facebook.com/dialog/oauth?scope=xmpp_login".
"&client_id=" . $app_id . "&redirect_uri=" . urlencode($my_url) ;
echo("<script>top.location.href='" . $dialog_url . "'</script>");
}
$token_url = "https://graph.facebook.com/oauth/access_token?client_id="
. $app_id . "&redirect_uri=" . urlencode($my_url)
. "&client_secret=" . $app_secret
. "&code=" . $code;
$access_token = file_get_contents($token_url);
parse_str($access_token, $output);
return($output['access_token']);
}
function _main() {
print "Test platform connect for XMPP<br>";
$app_id='';
$app_secret='';
$my_url = "";
$uid = '';
$access_token = get_access_token($app_id,$app_secret,$my_url);
print "access_token: ".$access_token."<br>";
$options = array(
'uid' => $uid,
'app_id' => $app_id,
'server' => 'chat.facebook.com',
);
// prints options used
print "server: ".$options['server']."<br>";
print "uid: ".$options['uid']."<br>";
print "app id: ".$options['app_id']."<br>";
if (xmpp_connect($options, $access_token)) {
print "Done<br>";
} else {
print "An error ocurred<br>";
}
}
_main();
?>
I know there is already a question like this here (facebook chat api - php). But it's a pretty old topic and maybe facebook changed something in their chat api.
You should send to socket command with your message. Common message format is
<message from="-sender_ID@chat.facebook.com" to="-receiver_ID@chat.facebook.com">
<body>message body</body>
</message>
So before comment "we made it!" insert function call send_xml with your message template
send_xml($fp, $MESSAGE);
if (!find_xmpp($fp, 'BODY')) {
return false;
}