基于node.js http-parser的PHP扩展，可用于实现纯异步PHP程序
libcurl提供了异步调用方式，有两种风格：
- ONE MULTI HANDLE MANY EASY HANDLES：加入多个easy handle后执行curl_multi_perform方法。该方法在php curl扩展中有对应实现。但最后一步curl_multi_perform是阻塞的。
- MULTI_SOCKET，这个是真正的非阻塞方法，但需要自行实现event loop，且封装较为困难，目前在php中没有对应实现。经过调研，curl_multi_socket_action跟php内核结合困难度很高。
除此之外，基本上没有真正的实现异步http请求的php扩展。目前仅有部分纯php实现的版本，比如tsf中的http client实现。 使用纯php实现的问题主要受限于http解析的性能。因此考虑将这一模块用扩展的方式来实现。node.js http-parser就是一个很好的c语言的http解析库。 php_http_parser就是对其做的一个封装，在php中暴露出相应的接口。
为了实现真正的非阻塞请求，仍然需要自己实现event loop。目前推荐结合swoole使用，以获得更好的性能。
$buffs = array("HTTP/1.1 301 Moved Permanently\r\n"
,"Location: http://www.google.com/\r\n"
,"Content-Type: text/html; charset=UTF-8\r\n"
,"Date: Sun, 26 Apr 2009 11:11:49 GMT\r\n"
,"Expires: Tue, 26 May 2009 11:11:49 GMT\r\n"
,"Cache-Control: public, max-age=2592000\r\n"
,"Server: gws\r\n"
,"Content-Length: 193\r\n"
,"\r\n"
,"<HTML><HEAD><meta http-equiv=\"content-type\" content=\"text/html;charset=utf-8\">\n"
,"<TITLE>301 Moved</TITLE></HEAD><BODY>\n"
,"<H1>301 Moved</H1>\n"
,"The document has moved\n"
,"<A HREF=\"http://www.google.com/\">here</A>.\r\n"
,"<A HREF=\"http://www.google.com/\">here</A>.\r\n"
,"<A HREF=\"http://www.google.com/\">here</A>.\r\n"
,"<A HREF=\"http://www.google.com/\">here</A>.\r\n"
,"<A HREF=\"http://www.google.com/\">here</A>.\r\n"
,"</BODY></HTML>\r\n");
$hp = new HttpParser();
foreach($buffs as $buff){
$ret = $hp->execute($buff);
if($ret !== false){
echo $ret;
break;
}
}虽然http请求可能分包发送，HttpParser会将所有包合并在一起后，出发body事件，然后调用相应的回调方法。 诸如header回调，目前暂未实现。另外，此处需要自行实现timeout逻辑。
示例代码是结合swoole_client与swPromise框架实现的一个异步http client。 籍此可以实现真正的非阻塞的PHP程序。
class HttpClientFuture implements FutureIntf {
protected $url = null;
protected $post = null;
protected $proxy = false;
public function __construct($url, $post = array(), $proxy = array()) {
$this->url = $url;
$this->post = $post;
if($proxy){
$this->proxy = $proxy;
}
}
public function run(Promise &$promise) {
$cli = new \swoole_client ( SWOOLE_TCP, SWOOLE_SOCK_ASYNC );
$urlInfo = parse_url ( $this->url );
if(!isset($urlInfo ['port']))$urlInfo ['port'] = 80;
$httpParser = new \HttpParser();
$cli->on ( "connect", function ($cli)use($urlInfo){
$host = $urlInfo['host'];
if($urlInfo['port'])$host .= ':'.$urlInfo['port'];
$req = array();
$req[] = "GET {$this->url} HTTP/1.1\r\n";
$req[] = "User-Agent: PHP swAsync\r\n";
$req[] = "Host:{$host}\r\n";
$req[] = "Connection:close\r\n";
$req[] = "\r\n";
$req = implode('', $req);
$cli->send ( $req );
} );
$cli->on ( "receive", function ($cli, $data = "") use(&$httpParser, &$promise) {
$ret = $httpParser->execute($data);
if($ret !== false){
$cli->close();
$promise->accept(['http_data'=>$ret]);
}
} );
$cli->on ( "error", function ($cli) use(&$promise) {
$promise->reject ();
} );
$cli->on ( "close", function ($cli) {
} );
if($this->proxy){
$cli->connect ( $this->proxy['host'], $this->proxy ['port'], 1 );
}else{
$cli->connect ( $urlInfo ['host'], $urlInfo ['port'], 1 );
}
}
}[web@gz-web01 php_http_parser]$ time /data/server/php/bin/php http_parser.php 2000000
real 0m11.489s
user 0m11.435s
sys 0m0.017s
1个worker进程
./http_load -fetches 20000 -parallel 100 9502.listasync
20000 fetches, 100 max parallel, 2.02e+06 bytes, in 5.94536 seconds
101 mean bytes/connection
3363.97 fetches/sec, 339761 bytes/sec
msecs/connect: 0.0473873 mean, 1.155 max, 0.019 min
msecs/first-response: 29.6366 mean, 51.736 max, 15.22 min
HTTP response codes:
code 200 -- 20000
-bash: history: write error: Success
2个worker进程
./http_load -fetches 20000 -parallel 100 9502.listasync
20000 fetches, 100 max parallel, 2.02e+06 bytes, in 3.17119 seconds
101 mean bytes/connection
6306.77 fetches/sec, 636984 bytes/sec
msecs/connect: 0.0643583 mean, 1.211 max, 0.023 min
msecs/first-response: 15.7489 mean, 32.425 max, 3.242 min
HTTP response codes:
code 200 -- 20000
-bash: history: write error: Success
4个woker进程
./http_load -fetches 20000 -parallel 100 9502.listasync
20000 fetches, 100 max parallel, 2.02e+06 bytes, in 1.57194 seconds
101 mean bytes/connection
12723.2 fetches/sec, 1.28504e+06 bytes/sec
msecs/connect: 0.0815263 mean, 1.349 max, 0.02 min
msecs/first-response: 7.65904 mean, 22.568 max, 1.221 min
HTTP response codes:
code 200 -- 20000
-bash: history: write error: Success
8个woker进程
./http_load -fetches 20000 -parallel 100 9502.listasync
20000 fetches, 100 max parallel, 2.02e+06 bytes, in 1.02967 seconds
101 mean bytes/connection
19423.8 fetches/sec, 1.9618e+06 bytes/sec
msecs/connect: 0.147502 mean, 1.575 max, 0.014 min
msecs/first-response: 3.17218 mean, 22.566 max, 0.339 min
HTTP response codes:
code 200 -- 20000
-bash: history: write error: Success