$f = fsockopen("www....",80,$x,$y);
fwrite("GET request HTTP/1.1'r'nConnection: keep-alive'r'n'r'n");
while($s = fread($f,1024)){
...
}
以上因Connection: keep-alive
而停滞不前,与Connection: close
一起工作。
你如何在不拖延的情况下做到这一点?
这取决于
响应,如果响应的transfer-encoding
是chunked
,那么你阅读直到遇到"最后一个块"('r'n0'r'n
)。
如果content-encoding
是gzip
,那么你查看content-length
响应标头并读取那么多数据,然后膨胀它。 如果transfer-encoding
也设置为分块,则必须对解码的响应进行分块。
最简单的方法是构建一个简单的状态机,在仍有数据留给响应时从套接字读取响应。
读取分块数据时,应读取第一个分块长度(以及任何分块扩展),然后读取与分块大小一样多的数据,并一直读取到最后一个分块。
换句话说:
- 读取 HTTP 响应标头(读取小块数据,直到遇到
'r'n'r'n
) - 将响应标头解析为数组
- 如果
transfer-encoding
是分块的,请逐段读取和分块数据。 - 如果设置了
content-length
标头,则可以从套接字读取大量数据 - 如果
content-encoding
为 gzip,则解压读取的数据
执行上述步骤后,您应该已经阅读了整个响应,现在可以在同一套接字上发送另一个 HTTP 请求并重复该过程。
另一方面,除非您绝对需要保持活动连接,否则只需在请求中设置Connection: close
,您就可以安全地读取while (!feof($f))
。
目前没有任何用于读取和解析HTTP响应的PHP代码(我只使用cURL),但是如果您想查看实际代码,请告诉我,我可以做一些事情。 我还可以向您推荐我制作的一些 C# 代码,这些代码可以完成上述所有操作。
编辑:这是使用fsockopen
发出HTTP请求并演示读取保持活动连接以及分块编码和gzip压缩可能性的工作代码。 经过测试,但未受到折磨 - 使用风险自负!!
<?php
/**
* PHP HTTP request demo
* Makes HTTP requests using PHP and fsockopen
* Supports chunked transfer encoding, gzip compression, and keep-alive
*
* @author drew010 <http://stackoverflow.com/questions/11125463/if-connection-is-keep-alive-how-to-read-until-end-of-stream-php/11812536#11812536>
* @date 2012-08-05
* Public domain
*
*/
error_reporting(E_ALL);
ini_set('display_errors', 1);
$host = 'www.kernel.org';
$sock = fsockopen($host, 80, $errno, $errstr, 30);
if (!$sock) {
die("Connection failed. $errno: $errstr'n");
}
request($sock, $host, 'GET', '/');
$headers = readResponseHeaders($sock, $resp, $msg);
$body = readResponseBody($sock, $headers);
echo "Response status: $resp - $msg'n'n";
echo '<pre>' . var_export($headers, true) . '</pre>';
echo "'n'n";
echo $body;
// if the connection is keep-alive, you can make another request here
// as demonstrated below
request($sock, $host, 'GET', '/kernel.css');
$headers = readResponseHeaders($sock, $resp, $msg);
$body = readResponseBody($sock, $headers);
echo "Response status: $resp - $msg'n'n";
echo '<pre>' . var_export($headers, true) . '</pre>';
echo "'n'n";
echo $body;
exit;
function request($sock, $host, $method = 'GET', $uri = '/', $params = null)
{
$method = strtoupper($method);
if ($method != 'GET' && $method != 'POST') $method = 'GET';
$request = "$method $uri HTTP/1.1'r'n"
."Host: $host'r'n"
."Connection: keep-alive'r'n"
."Accept-encoding: gzip, deflate'r'n"
."'r'n";
fwrite($sock, $request);
}
function readResponseHeaders($sock, &$response_code, &$response_status)
{
$headers = '';
$read = 0;
while (true) {
$headers .= fread($sock, 1);
$read += 1;
if ($read >= 4 && $headers[$read - 1] == "'n" && substr($headers, -4) == "'r'n'r'n") {
break;
}
}
$headers = parseHeaders($headers, $resp, $msg);
$response_code = $resp;
$response_status = $msg;
return $headers;
}
function readResponseBody($sock, array $headers)
{
$responseIsChunked = (isset($headers['transfer-encoding']) && stripos($headers['transfer-encoding'], 'chunked') !== false);
$contentLength = (isset($headers['content-length'])) ? $headers['content-length'] : -1;
$isGzip = (isset($headers['content-encoding']) && $headers['content-encoding'] == 'gzip') ? true : false;
$close = (isset($headers['connection']) && stripos($headers['connection'], 'close') !== false) ? true : false;
$body = '';
if ($contentLength >= 0) {
$read = 0;
do {
$buf = fread($sock, $contentLength - $read);
$read += strlen($buf);
$body .= $buf;
} while ($read < $contentLength);
} else if ($responseIsChunked) {
$body = readChunked($sock);
} else if ($close) {
while (!feof($sock)) {
$body .= fgets($sock, 1024);
}
}
if ($isGzip) {
$body = gzinflate(substr($body, 10));
}
return $body;
}
function readChunked($sock)
{
$body = '';
while (true) {
$data = '';
do {
$data .= fread($sock, 1);
} while (strpos($data, "'r'n") === false);
if (strpos($data, ' ') !== false) {
list($chunksize, $chunkext) = explode(' ', $data, 2);
} else {
$chunksize = $data;
$chunkext = '';
}
$chunksize = (int)base_convert($chunksize, 16, 10);
if ($chunksize === 0) {
fread($sock, 2); // read trailing "'r'n"
return $body;
} else {
$data = '';
$datalen = 0;
while ($datalen < $chunksize + 2) {
$data .= fread($sock, $chunksize - $datalen + 2);
$datalen = strlen($data);
}
$body .= substr($data, 0, -2); // -2 to remove the "'r'n" before the next chunk
}
} // while (true)
}
function parseHeaders($headers, &$response_code = null, &$response_message = null)
{
$lines = explode("'r'n", $headers);
$return = array();
$response = array_shift($lines);
if (func_num_args() > 1) {
list($proto, $code, $message) = explode(' ', $response, 3);
$response_code = $code;
if (func_num_args() > 2) {
$response_message = $message;
}
}
foreach($lines as $header) {
if (trim($header) == '') continue;
list($name, $value) = explode(':', $header, 2);
$return[strtolower(trim($name))] = trim($value);
}
return $return;
}
以下代码对我来说没有任何问题:
<?php
$f = fsockopen("www.google.de",80);
fwrite($f,"GET / HTTP/1.1'r'n Connection: keep-alive'r'n'r'n");
while($s = fread($f,1024)){
echo "got: $s";
}
echo "finished;";
?>
有趣的是,如果没有保持活力,这个例子对我来说就会停滞不前。你能添加一个可以复制和粘贴并显示你的错误的例子吗?