<?php
/*
* Copyright 2013 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* Abstract IO base class
*/
if (!defined('ABSPATH')) die('No direct access allowed');
if (!class_exists('UDP_Google_Client')) {
require_once dirname(__FILE__) . '/../autoload.php';
}
abstract class UDP_Google_IO_Abstract
{
const UNKNOWN_CODE = 0;
const FORM_URLENCODED = 'application/x-www-form-urlencoded';
private static $CONNECTION_ESTABLISHED_HEADERS = array(
"HTTP/1.0 200 Connection established\r\n\r\n",
"HTTP/1.1 200 Connection established\r\n\r\n",
);
private static $ENTITY_HTTP_METHODS = array("POST" => null, "PUT" => null);
private static $HOP_BY_HOP = array(
'connection' => true,
'keep-alive' => true,
'proxy-authenticate' => true,
'proxy-authorization' => true,
'te' => true,
'trailers' => true,
'transfer-encoding' => true,
'upgrade' => true
);
/** @var UDP_Google_Client */
protected $client;
public function __construct(UDP_Google_Client $client)
{
$this->client = $client;
$timeout = $client->getClassConfig('UDP_Google_IO_Abstract', 'request_timeout_seconds');
if ($timeout > 0) {
$this->setTimeout($timeout);
}
}
/**
* Executes a Google_Http_Request
* @param Google_Http_Request $request the http request to be executed
* @return array containing response headers, body, and http code
* @throws UDP_Google_IO_Exception on curl or IO error
*/
abstract public function executeRequest(UDP_Google_Http_Request $request);
/**
* Set options that update the transport implementation's behavior.
* @param $options
*/
abstract public function setOptions($options);
/**
* Set the maximum request time in seconds.
* @param $timeout in seconds
*/
abstract public function setTimeout($timeout);
/**
* Get the maximum request time in seconds.
* @return timeout in seconds
*/
abstract public function getTimeout();
/**
* Test for the presence of a cURL header processing bug
*
* The cURL bug was present in versions prior to 7.30.0 and caused the header
* length to be miscalculated when a "Connection established" header added by
* some proxies was present.
*
* @return boolean
*/
abstract protected function needsQuirk();
/**
* @visible for testing.
* Cache the response to an HTTP request if it is cacheable.
* @param Google_Http_Request $request
* @return bool Returns true if the insertion was successful.
* Otherwise, return false.
*/
public function setCachedRequest(UDP_Google_Http_Request $request)
{
// Determine if the request is cacheable.
if (Google_Http_CacheParser::isResponseCacheable($request)) {
$this->client->getCache()->set($request->getCacheKey(), $request);
return true;
}
return false;
}
/**
* Execute an HTTP Request
*
* @param Google_Http_Request $request the http request to be executed
* @return Google_Http_Request http request with the response http code,
* response headers and response body filled in
* @throws UDP_Google_IO_Exception on curl or IO error
*/
public function makeRequest(UDP_Google_Http_Request $request)
{
// First, check to see if we have a valid cached version.
$cached = $this->getCachedRequest($request);
if ($cached !== false && $cached instanceof UDP_Google_Http_Request) {
if (!$this->checkMustRevalidateCachedRequest($cached, $request)) {
return $cached;
}
}
if (array_key_exists($request->getRequestMethod(), self::$ENTITY_HTTP_METHODS)) {
$request = $this->processEntityRequest($request);
}
list($responseData, $responseHeaders, $respHttpCode) = $this->executeRequest($request);
if ($respHttpCode == 304 && $cached) {
// If the server responded NOT_MODIFIED, return the cached request.
$this->updateCachedRequest($cached, $responseHeaders);
return $cached;
}
if (!isset($responseHeaders['Date']) && !isset($responseHeaders['date'])) {
$responseHeaders['date'] = gmdate("r");
}
$request->setResponseHttpCode($respHttpCode);
$request->setResponseHeaders($responseHeaders);
$request->setResponseBody($responseData);
// Store the request in cache (the function checks to see if the request
// can actually be cached)
$this->setCachedRequest($request);
return $request;
}
/**
* @visible for testing.
* @param Google_Http_Request $request
* @return Google_Http_Request|bool Returns the cached object or
* false if the operation was unsuccessful.
*/
public function getCachedRequest(UDP_Google_Http_Request $request)
{
if (false === Google_Http_CacheParser::isRequestCacheable($request)) {
return false;
}
return $this->client->getCache()->get($request->getCacheKey());
}
/**
* @visible for testing
* Process an http request that contains an enclosed entity.
* @param Google_Http_Request $request
* @return Google_Http_Request Processed request with the enclosed entity.
*/
public function processEntityRequest(UDP_Google_Http_Request $request)
{
$postBody = $request->getPostBody();
$contentType = $request->getRequestHeader("content-type");
// Set the default content-type as application/x-www-form-urlencoded.
if (false == $contentType) {
$contentType = self::FORM_URLENCODED;
$request->setRequestHeaders(array('content-type' => $contentType));
}
// Force the payload to match the content-type asserted in the header.
if ($contentType == self::FORM_URLENCODED && is_array($postBody)) {
$postBody = http_build_query($postBody, '', '&');
$request->setPostBody($postBody);
}
// Make sure the content-length header is set.
if (!$postBody || is_string($postBody)) {
$postsLength = strlen($postBody);
$request->setRequestHeaders(array('content-length' => $postsLength));
}
return $request;
}
/**
* Check if an already cached request must be revalidated, and if so update
* the request with the correct ETag headers.
* @param Google_Http_Request $cached A previously cached response.
* @param Google_Http_Request $request The outbound request.
* return bool If the cached object needs to be revalidated, false if it is
* still current and can be re-used.
*/
protected function checkMustRevalidateCachedRequest($cached, $request)
{
if (Google_Http_CacheParser::mustRevalidate($cached)) {
$addHeaders = array();
if ($cached->getResponseHeader('etag')) {
// [13.3.4] If an entity tag has been provided by the origin server,
// we must use that entity tag in any cache-conditional request.
$addHeaders['If-None-Match'] = $cached->getResponseHeader('etag');
} elseif ($cached->getResponseHeader('date')) {
$addHeaders['If-Modified-Since'] = $cached->getResponseHeader('date');
}
$request->setRequestHeaders($addHeaders);
return true;
} else {
return false;
}
}
/**
* Update a cached request, using the headers from the last response.
* @param Google_Http_Request $cached A previously cached response.
* @param mixed Associative array of response headers from the last request.
*/
protected function updateCachedRequest($cached, $responseHeaders)
{
$hopByHop = self::$HOP_BY_HOP;
if (!empty($responseHeaders['connection'])) {
$connectionHeaders = array_map(
'strtolower',
array_filter(
array_map('trim', explode(',', $responseHeaders['connection']))
)
);
$hopByHop += array_fill_keys($connectionHeaders, true);
}
$endToEnd = array_diff_key($responseHeaders, $hopByHop);
$cached->setResponseHeaders($endToEnd);
}
/**
* Used by the IO lib and also the batch processing.
*
* @param $respData
* @param $headerSize
* @return array
*/
public function parseHttpResponse($respData, $headerSize)
{
// check proxy header
foreach (self::$CONNECTION_ESTABLISHED_HEADERS as $established_header) {
if (stripos($respData, $established_header) !== false) {
// existed, remove it
$respData = str_ireplace($established_header, '', $respData);
// Subtract the proxy header size unless the cURL bug prior to 7.30.0
// is present which prevented the proxy header size from being taken into
// account.
if (!$this->needsQuirk()) {
$headerSize -= strlen($established_header);
}
break;
}
}
if ($headerSize) {
$responseBody = substr($respData, $headerSize);
$responseHeaders = substr($respData, 0, $headerSize);
} else {
$responseSegments = explode("\r\n\r\n", $respData, 2);
$responseHeaders = $responseSegments[0];
$responseBody = isset($responseSegments[1]) ? $responseSegments[1] :
null;
}
$responseHeaders = $this->getHttpResponseHeaders($responseHeaders);
return array($responseHeaders, $responseBody);
}
/**
* Parse out headers from raw headers
* @param rawHeaders array or string
* @return array
*/
public function getHttpResponseHeaders($rawHeaders)
{
if (is_array($rawHeaders)) {
return $this->parseArrayHeaders($rawHeaders);
} else {
return $this->parseStringHeaders($rawHeaders);
}
}
private function parseStringHeaders($rawHeaders)
{
$headers = array();
$responseHeaderLines = explode("\r\n", $rawHeaders);
foreach ($responseHeaderLines as $headerLine) {
if ($headerLine && strpos($headerLine, ':') !== false) {
list($header, $value) = explode(': ', $headerLine, 2);
$header = strtolower($header);
if (isset($headers[$header])) {
$headers[$header] .= "\n" . $value;
} else {
$headers[$header] = $value;
}
}
}
return $headers;
}
private function parseArrayHeaders($rawHeaders)
{
$header_count = count($rawHeaders);
$headers = array();
for ($i = 0; $i < $header_count; $i++) {
$header = $rawHeaders[$i];
// Times will have colons in - so we just want the first match.
$header_parts = explode(': ', $header, 2);
if (count($header_parts) == 2) {
$headers[strtolower($header_parts[0])] = $header_parts[1];
}
}
return $headers;
}
}