curl发出请求

最近写了几个使用php curl来获取数据的脚本. 在这里把几个脚本捏合到一起, 能够满足绝大部分curl请求了.

主要功能包括:

1. 支持https.
2. 支持 post, get, head 3中请求方式
3. 支持超时检查.
4. 支持访问指定ip+host的请求.
5. 支持带cookie请求.
6. 返回结果异常时, 返回curl_getinfo等信息方便排错.

function request($url, $mode, array $params=array(),  $cookie='', $host=''){
    $mode = strtoupper($mode);
    $timeout = 10;
    $userAgent = 'CODE_SAY_(.)(.)_';

    $ch = curl_init();
    if(substr($url, 0, 5) == 'https'){
        curl_setopt($ch, CURLOPT_SSLVERSION, 3);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    }
    # curl 执行超时 (how long to wait to receive a completely buffered output from the server)
    curl_setopt($ch, CURLOPT_TIMEOUT,  $timeout);
    # curl 连接超时(how long to wait to make a successful connection to the server before starting to buffer the output. )
    curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
    curl_setopt($ch, CURLOPT_USERAGENT, $userAgent);
    # 文件流的方式返回，而非直接输出
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);

    # 访问某个域名下指定$host的机器
    if(!empty($host)){
        $parts = explode('/', $url);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array('Host: '.$parts[2]));
        $parts[2] = $host;
        $url = implode('/', $parts);
    }
    curl_setopt($ch, CURLOPT_COOKIE, $cookie);

    if($mode=='POST'){
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($params));
    }else if($mode == 'HEAD'){
        curl_setopt($ch, CURLOPT_HEADER, true);
        curl_setopt($ch, CURLOPT_NOBODY, true);
        $url .= empty($params) ? '' : ((strpos($url,'?')===false?'?':'&') . http_build_query($params));
    }else{
        $url .= empty($params) ? '' : ((strpos($url,'?')===false?'?':'&') . http_build_query($params));
    }
    curl_setopt($ch, CURLOPT_URL, $url);
    $result = curl_exec($ch);
    if($result === false){
        $result['curl_errno'] = curl_errno($ch);
        $result['curl_error'] = curl_error($ch);
        $result['curl_getinfo']  = curl_getinfo($ch);
    }
    curl_close($ch);
    return $result;
}
/*
如果需要获得header+body, 必须使用非head请求
curl_setopt($ch, CURLOPT_HEADER, true);
$info = curl_getinfo($ch);
$result['header'] = substr($tmp, 0, $info['header_size']);
$result['body']   = substr($tmp, -$info['download_content_length']);
*/

CURLOPT_TIMEOUT: how long to wait to receive a completely buffered output from the server

CURLOPT_CONNECTTIMEOUT: how long to wait to make a successful connection to the server before starting to buffer the output.

以下载一个mp3文件为例：connecttimeout是指由请求发出开始到收到请求头的第一个字符；timeout是指请求发出开始到完整接收整个mp3文件的时间。

代码添加了一个功能：指定参数host，按照ip来访问http服务器。