A simple encapsulated HTTP class for PHP

<?php

/* Version 0.9, 6th April 2003 - Simon Willison ( http://simon.incutio.com/ )
   Manual: http://scripts.incutio.com/httpclient/
*/

class HttpClient {
    // Request vars
    var $host;
    var $port;
    var $path;
    var $method;
    var $postdata = &#39;&#39;;
    var $cookies = array();
    var $referer;
    var $accept = &#39;text/xml,application/xml,application/xhtml+xml,text/html,text/plain,image/png,image/jpeg,image/gif,*/*&#39;;
    var $accept_encoding = &#39;gzip&#39;;
    var $accept_language = &#39;en-us&#39;;
    var $user_agent = &#39;Incutio HttpClient v0.9&#39;;
    // Options
    var $timeout = 20;
    var $use_gzip = true;
    var $persist_cookies = true;  // If true, received cookies are placed in the $this->cookies array ready for the next request
    // Note: This currently ignores the cookie path (and time) completely. Time is not important,
    //       but path could possibly lead to security problems.
    var $persist_referers = true; // For each request, sends path of last request as referer
    var $debug = false;
    var $handle_redirects = true; // Auaomtically redirect if Location or URI header is found
    var $max_redirects = 5;
    var $headers_only = false;    // If true, stops receiving once headers have been read.
    // Basic authorization variables
    var $username;
    var $password;
    // Response vars
    var $status;
    var $headers = array();
    var $content = '';
    var $errormsg;
    // Tracker variables
    var $redirect_count = 0;
    var $cookie_host = '';
    function HttpClient($host, $port=80) {
        $this->host = $host;
        $this->port = $port;
    }

    /**
     * as the HttpClient Manual said:
     * Executes a GET request for the specified path. If $data is specified, appends it to a query string as part of the get request.
     * $data can be an array of key value pairs, in which case a matching query string will be constructed. Returns true on success and false on failure.
     * If false, an error message describing the problem encountered can be accessed using the getError() method.
     * for example: like  http://ecc.tencent.com/index.php?c=job&m=req
     *
     * @param $path ecc.tencent.com
     * @param bool $data ["c"=>"job","m"="req"]
     * @return bool
     */
    function get($path, $data = false) {
        $this->path = $path;
        $this->method = 'GET';
        if ($data) {
            //$this->path .= '?'.$this->buildQueryString($data);
            $this->path .= $this->buildQueryString($data);
        }
        return $this->doRequest();
    }

    /**
     * Executes a POST request to the specified path, sending the information from specified in $data.
     * $data can be an array of key value pairs, in which case a matching post request will be constructed.
     * Returns true on success and false on failure. If false, an error message describing the problem encountered can be accessed using the getError() method.
     *
     * @param $path
     * @param $data
     * @return bool
     */
    function post($path, $data) {
        $this->path = $path;
        $this->method = 'POST';
        $this->postdata = $this->buildQueryString($data);
        return $this->doRequest();
    }


    function buildQueryString($data) {
        $querystring = '';
        if (is_array($data)) {
            // Change data in to postable data
            foreach ($data as $key => $val) {
                if (is_array($val)) {
                    foreach ($val as $val2) {
                        $querystring .= urlencode($key).'='.urlencode($val2).'&';
                    }
                } else {
                    $querystring .= urlencode($key).'='.urlencode($val).'&';
                }
            }
            $querystring = substr($querystring, 0, -1); // Eliminate unnecessary &
        } else {
            $querystring = $data;
        }
        return $querystring;
    }
    function doRequest() {
        // Performs the actual HTTP request, returning true or false depending on outcome
        if (!$fp = @fsockopen($this->host, $this->port, $errno, $errstr, $this->timeout)) {
            // Set error message
            switch($errno) {
                case -3:
                    $this->errormsg = 'Socket creation failed (-3)';
                case -4:
                    $this->errormsg = 'DNS lookup failure (-4)';
                case -5:
                    $this->errormsg = 'Connection refused or timed out (-5)';
                default:
                    $this->errormsg = 'Connection failed ('.$errno.')';
                    $this->errormsg .= ' '.$errstr;
                    $this->debug($this->errormsg);
            }
            return false;
        }
        socket_set_timeout($fp, $this->timeout);
        $request = $this->buildRequest();
        $this->debug('Request', $request);
        fwrite($fp, $request);
        // Reset all the variables that should not persist between requests
        $this->headers = array();
        $this->content = '';
        $this->errormsg = '';
        // Set a couple of flags
        $inHeaders = true;
        $atStart = true;
        // Now start reading back the response
        while (!feof($fp)) {
            $line = fgets($fp, 4096);
            if ($atStart) {
                // Deal with first line of returned data
                $atStart = false;
                if (!preg_match('/HTTP\/(\\d\\.\\d)\\s*(\\d+)\\s*(.*)/', $line, $m)) {
                    $this->errormsg = "Status code line invalid: ".htmlentities($line);
                    $this->debug($this->errormsg);
                    return false;
                }
                $http_version = $m[1]; // not used
                $this->status = $m[2];
                $status_string = $m[3]; // not used
                $this->debug(trim($line));
                continue;
            }
            if ($inHeaders) {
                if (trim($line) == '') {
                    $inHeaders = false;
                    $this->debug('Received Headers', $this->headers);
                    if ($this->headers_only) {
                        break; // Skip the rest of the input
                    }
                    continue;
                }
                if (!preg_match('/([^:]+):\\s*(.*)/', $line, $m)) {
                    // Skip to the next header
                    continue;
                }
                $key = strtolower(trim($m[1]));
                $val = trim($m[2]);
                // Deal with the possibility of multiple headers of same name
                if (isset($this->headers[$key])) {
                    if (is_array($this->headers[$key])) {
                        $this->headers[$key][] = $val;
                    } else {
                        $this->headers[$key] = array($this->headers[$key], $val);
                    }
                } else {
                    $this->headers[$key] = $val;
                }
                continue;
            }
            // We're not in the headers, so append the line to the contents
            $this->content .= $line;
        }
        fclose($fp);
        // If data is compressed, uncompress it
        if (isset($this->headers['content-encoding']) && $this->headers['content-encoding'] == 'gzip') {
            $this->debug('Content is gzip encoded, unzipping it');
            $this->content = substr($this->content, 10); // See http://www.php.net/manual/en/function.gzencode.php
            $this->content = gzinflate($this->content);
        }
        // If $persist_cookies, deal with any cookies
        if ($this->persist_cookies && isset($this->headers['set-cookie']) && $this->host == $this->cookie_host) {
            $cookies = $this->headers['set-cookie'];
            if (!is_array($cookies)) {
                $cookies = array($cookies);
            }
            foreach ($cookies as $cookie) {
                if (preg_match('/([^=]+)=([^;]+);/', $cookie, $m)) {
                    $this->cookies[$m[1]] = $m[2];
                }
            }
            // Record domain of cookies for security reasons
            $this->cookie_host = $this->host;
        }
        // If $persist_referers, set the referer ready for the next request
        if ($this->persist_referers) {
            $this->debug('Persisting referer: '.$this->getRequestURL());
            $this->referer = $this->getRequestURL();
        }
        // Finally, if handle_redirects and a redirect is sent, do that
        if ($this->handle_redirects) {
            if (++$this->redirect_count >= $this->max_redirects) {
                $this->errormsg = 'Number of redirects exceeded maximum ('.$this->max_redirects.')';
                $this->debug($this->errormsg);
                $this->redirect_count = 0;
                return false;
            }
            $location = isset($this->headers['location']) ? $this->headers['location'] : '';
            $uri = isset($this->headers['uri']) ? $this->headers['uri'] : '';
            if ($location || $uri) {
                $url = parse_url($location.$uri);
                // This will FAIL if redirect is to a different site
                return $this->get($url['path']);
            }
        }
        return true;
    }

    //拼装header
    function buildRequest() {
        $headers = array();
        $headers[] = "{$this->method} {$this->path} HTTP/1.0"; // Using 1.1 leads to all manner of problems, such as "chunked" encoding
        $headers[] = "Host: {$this->host}";
        $headers[] = "User-Agent: {$this->user_agent}";
        $headers[] = "Accept: {$this->accept}";
        if ($this->use_gzip) {
            $headers[] = "Accept-encoding: {$this->accept_encoding}";
        }
        $headers[] = "Accept-language: {$this->accept_language}";
        if ($this->referer) {
            $headers[] = "Referer: {$this->referer}";
        }
        // Cookies
        if ($this->cookies) {
            $cookie = 'Cookie: ';
            foreach ($this->cookies as $key => $value) {
                $cookie .= "$key=$value; ";
            }
            $headers[] = $cookie;
        }
        // Basic authentication
        if ($this->username && $this->password) {
            $headers[] = 'Authorization: BASIC '.base64_encode($this->username.':'.$this->password);
        }
        // If this is a POST, set the content type and length
        if ($this->postdata) {
            $headers[] = 'Content-Type: application/x-www-form-urlencoded';
            $headers[] = 'Content-Length: '.strlen($this->postdata);
        }
        $request = implode("\r\n", $headers)."\r\n\r\n".$this->postdata;
        return $request;
    }
    function getStatus() {
        return $this->status;
    }
    function getContent() {
        return $this->content;
    }
    function getHeaders() {
        return $this->headers;
    }
    function getHeader($header) {
        $header = strtolower($header);
        if (isset($this->headers[$header])) {
            return $this->headers[$header];
        } else {
            return false;
        }
    }
    function getError() {
        return $this->errormsg;
    }
    function getCookies() {
        return $this->cookies;
    }
    function getRequestURL() {
        $url = 'http://'.$this->host;
        if ($this->port != 80) {
            $url .= ':'.$this->port;
        }
        $url .= $this->path;
        return $url;
    }
    // Setter methods
    function setUserAgent($string) {
        $this->user_agent = $string;
    }
    function setAuthorization($username, $password) {
        $this->username = $username;
        $this->password = $password;
    }
    function setCookies($array) {
        $this->cookies = $array;
    }
    // Option setting methods
    function useGzip($boolean) {
        $this->use_gzip = $boolean;
    }
    function setPersistCookies($boolean) {
        $this->persist_cookies = $boolean;
    }
    function setPersistReferers($boolean) {
        $this->persist_referers = $boolean;
    }
    function setHandleRedirects($boolean) {
        $this->handle_redirects = $boolean;
    }
    function setMaxRedirects($num) {
        $this->max_redirects = $num;
    }
    function setHeadersOnly($boolean) {
        $this->headers_only = $boolean;
    }
    function setDebug($boolean) {
        $this->debug = $boolean;
    }
    // "Quick" static methods
    function quickGet($url) {
        $bits = parse_url($url);
        $host = $bits['host'];
        $port = isset($bits['port']) ? $bits['port'] : 80;
        $path = isset($bits['path']) ? $bits['path'] : '/';
        if (isset($bits['query'])) {
            $path .= '?'.$bits['query'];
        }
        $client = new HttpClient($host, $port);
        if (!$client->get($path)) {
            return false;
        } else {
            return $client->getContent();
        }
    }
    function quickPost($url, $data) {
        $bits = parse_url($url);
        $host = $bits['host'];
        $port = isset($bits['port']) ? $bits['port'] : 80;
        $path = isset($bits['path']) ? $bits['path'] : '/';
        $client = new HttpClient($host, $port);
        if (!$client->post($path, $data)) {
            return false;
        } else {
            return $client->getContent();
        }
    }
    function debug($msg, $object = false) {
        if ($this->debug) {
            print '<div style="border: 1px solid red; padding: 0.5em; margin: 0.5em;"><strong>HttpClient Debug:</strong> '.$msg;
            if ($object) {
                ob_start();
                print_r($object);
                $content = htmlentities(ob_get_contents());
                ob_end_clean();
                print '<pre class="brush:php;toolbar:false">'.$content.'