/**
* Executes a request.
* This is a pretty generic PHP function for the most part. The only parts that are specific to Picasa
* is the errors that are thrown. PHP doesn't have a built in function that does this very well (although there are packages
* for it that can be installed), so this manually sets the HTTP headers and parses the whole response.
*
* @access protected
* @static
* @param string $host The destination address to send the request to. It should not include a protocol.
* @param string $path The path on the host to send the request to. It should start with a "/"
* @param string $data Any data that should be sent along with the request. If there is no data, leave it as null.
* @param string $request The type of request to perform. Most common are GET, POST, PUT, and DELETE. The type of
* request to use for each Picasa function is defined in Picasa's official documentation.
* @param array $specialHeaders An array of strings of headers that should be sent with the request. The headers that are
* always sent are Host, Content-Type, and Content-Length. The most common type of special
* header is an authorization header from Google. Note that even if there is only one special header,
* it still must be in an array. Also note that each line in the array should end in "\r\n" and
* should be set in the array with double quotes, not single quotes, because "\r\n" is interpreted
* differently by PHP if single quotes are used. Optional, the default is null.
* @param string $type The type of content that will is being sent through the request. Optional, the default is
* "application/x-www-form-urlencoded".
* @param string $protocol The protocol to use when sending the request. Secure requests should use "ssl://". Note that
* the protocol must end in "://" unless it's an empty string. For HTTP, this parameter can be left
* as an empty string. Optional, the default is an empty string.
* @param int $port The port number to send the request to. Different protocols have different port numbers. HTTP protocol
* uses port 80 and SSL uses port 443. Optional, the default is 80.
* @return string The entire response, including headers, that was recieved from the host.
* @throws {@link Picasa_Exception} If a response of "200" or "201" is not recieved. In this case, the entire contents of the response,
* including headers, is set to the $response field of the exception and the error supplied by
* Picasa is set as the exceptions message. The idea is that the calling method can search the
* response for a specific return code (for instance, a File Not Found or Forbidden error) and throw
* a more specific exception. The caller can also search the response for values that are specific
* to its request, such as a Captcha URL.
*/
protected static function do_request($host, $path, $data, $request, $specialHeaders = null, $type = "application/x-www-form-urlencoded", $protocol = "", $port = "80")
{
$contentlen = strlen($data);
$req = "{$request} {$path} HTTP/1.1\r\nHost: {$host}\r\nContent-Type: {$type}\r\nContent-Length: {$contentlen}\r\n";
if (is_array($specialHeaders)) {
foreach ($specialHeaders as $header) {
$req .= $header;
}
}
$req .= "Connection: close\r\n\r\n";
if ($data != null) {
$req .= $data;
}
Picasa_Logger::getLogger()->logIfEnabled("Request to do: " . $request);
$fp = fsockopen($protocol . $host, $port, $errno, $errstr);
if (!$fp) {
throw new Picasa_Exception($errstr);
}
fputs($fp, $req);
$buf = "";
if (!feof($fp)) {
$buf = @fgets($fp);
}
Picasa_Logger::getLogger()->logIfEnabled("Buffer returned: " . $buf);
// If either a 200 or 201 response is not found, there was a problem so throw an exception
if (preg_match("/200 /i", $buf) || preg_match("/201 /i", $buf)) {
while (!feof($fp)) {
$buf .= @fgets($fp);
}
fclose($fp);
return $buf;
} else {
/* In the response returned from Picasa, it is really hard to pull out the error message.
* Its location is two lines below the "Connection: Close" line. So that message is pulled
* out, if possible, and set as the Exception's message. Also, the entire buffer is sent.
* This way, the caller can throw it's own message by looking for its own response code.
*/
$expMessage = "An unknown error has occured while sending a {$request} request.";
$break = false;
$tmpBuf = "";
while (!feof($fp)) {
$tmpBuf = @fgets($fp);
$buf .= $tmpBuf;
if (strcmp($tmpBuf, "Connection: Close\r\n") == 0) {
for ($i = 0; !feof($fp); $i++) {
if ($i == 2) {
$expMessage = @fgets($fp);
$buf .= $expMessage;
$break = true;
} else {
$buf .= @fgets($fp);
}
}
}
}
if (!$break) {
$msg = Picasa::getResponseValue($buf, "Error");
if ($msg != null) {
$expMessage = $msg;
}
}
throw new Picasa_Exception($expMessage, $buf, $host . $path);
}
}
