/**
* call a web service
*
* This function supports following protocols, as specified in last parameter:
* - 'XML-RPC' - request and response are XML snippets
* - 'JSON-RPC' - request and response are JSON snippets
*
* Minimum example:
* [php]
* $result = Call::invoke($url, $method);
* if(!$result[0])
* echo $result[1]; // error message
* else
* ... // use call result from $result[1]
* [/php]
*
* Note that in a previous version data was encoded.
* Unfortunately, most servers do not handle encoding, despite it's a useful web standard.
*
* @param string the url to use
* @param string the service to call
* @param array the parameters to transmit
* @param string the protocol to use
* @return an array of which the first value indicates call success or failure
*
* @see control/scan.php
* @see links/links.php
* @see servers/servers.php
* @see services/blog_test.php
*/
public static function invoke($url, $service, $parameters = NULL, $variant = 'XML-RPC')
{
global $context;
// submit a raw request
$raw_request = FALSE;
if ($variant == 'raw') {
$raw_request = TRUE;
$variant = 'XML-RPC';
}
// select a codec handler
include_once $context['path_to_root'] . 'services/codec.php';
$codec = Codec::initialize($variant);
if (!is_object($codec)) {
return array(FALSE, 'Do not know how to cope with API ' . $variant);
}
// adjust content type
if ($variant == 'JSON-RPC') {
$headers = 'Content-Type: application/json' . CRLF;
} else {
$headers = 'Content-Type: text/xml' . CRLF;
}
// build the request
if ($raw_request) {
$result = array(TRUE, $parameters);
} else {
$result = $codec->export_request($service, $parameters);
}
if (!$result[0]) {
return array(FALSE, $result[1]);
}
$headers .= 'Content-Length: ' . strlen($result[1]) . CRLF;
// parse the target URL
$items = @parse_url($url);
// no host, assume it's us
if (!isset($items['host']) || !($host = $items['host'])) {
$host = $context['host_name'];
}
// no port, assume the standard
if (!isset($items['port']) || !($port = $items['port'])) {
$port = 80;
}
// outbound web is not authorized
if (isset($context['without_outbound_http']) && $context['without_outbound_http'] == 'Y') {
return array(FALSE, 'Outbound HTTP is not authorized.');
}
// connect to the server
if (!($handle = Safe::fsockopen($host, $port, $errno, $errstr, 30))) {
return array(FALSE, sprintf('Impossible to connect to %s.', $host . ':' . $port));
}
// ensure enough execution time
Safe::set_time_limit(30);
// build the path, including any query
$path = $items['path'];
if (!$path) {
$path = '/';
}
if (isset($items['query']) && $items['query']) {
$path .= '?' . $items['query'];
}
// build an HTTP request
$request = "POST " . $path . " HTTP/1.0" . CRLF . 'Host: ' . $host . CRLF . "Accept-Encoding: gzip" . CRLF . "User-Agent: YACS (www.yacs.fr)" . CRLF . "Connection: close" . CRLF . $headers . CRLF . $result[1];
// save the request if debug mode
if (isset($context['debug_call']) && $context['debug_call'] == 'Y') {
Logger::remember('services/call.php: Call::invoke() request', str_replace("\r\n", "\n", $request), 'debug');
}
// submit the request
fputs($handle, $request);
// get everything by Ethernet-sized chunks
$response = '';
while (!feof($handle) && strlen($response) < 5242880) {
$response .= fread($handle, 1500);
}
fclose($handle);
// ensure we have a valid HTTP status line
if (preg_match('/^HTTP/', $response) && !preg_match('/^HTTP\\/[0-9\\.]+ 200 /', $response)) {
$lines = explode("\n", $response, 2);
return array(FALSE, 'Unexpected HTTP status "' . $lines[0] . '"');
}
// separate headers from body
list($headers, $content) = explode(CRLF . CRLF, $response, 2);
// uncompress payload if necessary
if (preg_match('/Content-Encoding: \\s*gzip/i', $headers)) {
$content = gzinflate(substr($content, 10));
}
// save the response if debug mode
if (isset($context['debug_call']) && $context['debug_call'] == 'Y') {
Logger::remember('services/call.php: Call::invoke() response', str_replace("\r\n", "\n", $headers . "\n\n" . $content), 'debug');
}
// decode the result
return $codec->import_response($content, $headers, $parameters);
}
