为什么 PHP/Curl 不保留会话的 cookie 数据

Question

我正在使用Webbots, Spiders, and Screen Scrapers, 2nd Edition 学习 PHP Curl。关于cookie认证的章节显示了这段代码：

# Define target page 
$target = "http://www.WebbotsSpidersScreenScrapers.com/cookie_authentication/index.php";
# Define the login form data
$form_data="enter=Enter&username=webbot&password=sp1der3";
# Create the PHP/CURL session
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $target); // Define target site
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE); // Return page in string
curl_setopt($ch, CURLOPT_COOKIEJAR, "cookies.txt"); // Tell PHP/CURL where to write cookies
curl_setopt($ch, CURLOPT_COOKIEFILE, "cookies.txt"); // Tell PHP/CURL which cookies to send
curl_setopt($ch, CURLOPT_POST, TRUE); 
curl_setopt($ch, CURLOPT_POSTFIELDS, $form_data);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, TRUE); // Follow redirects
# Execute the PHP/CURL session and echo the downloaded page
$page = curl_exec($ch);
echo $page; 
# Close the PHP/CURL session
curl_close($ch);

当我使用网络浏览器登录测试网站时，我收到消息“您的登录还可以再使用 3600 秒”，每当我重新加载页面时，我都会看到时间下降（这是完全正常的行为，因为服务器识别会话编号并处理与之相关的所有内容，包括之前的时间）。现在，当我运行示例代码（如上所列）时，每次运行脚本时，身份验证值都会不断变化。我的猜测是因为 curl_setopt($ch, CURLOPT_COOKIEJAR, "cookies.txt"); 指令。但这里是这样想的：即使我注释了阻止脚本更改 cookie 的那一行，脚本仍然从服务器获得“相同”的响应（登录在 3600 - 3599 秒内仍然有效）。这可以通过某种方式解决吗？

Answer 1

您的问题是您没有使用 curl 的 cookie 会话。

尝试像这样设置 cookie 会话：

curl_setopt( $ch, CURLOPT_COOKIESESSION, true );

工作示例：

function getSessionTime($answer) {

    $parts      = explode('<font color="red">', $answer);
    $bottomPart = $parts[1];
    $parts      = explode('</font>', $bottomPart);
    $result     = $parts[0];

    return $result;
}

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'http://www.WebbotsSpidersScreenScrapers.com/cookie_authentication/index.php');
curl_setopt($ch, CURLOPT_USERAGENT, 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/32.0.1700.107 Chrome/32.0.1700.107 Safari/537.36');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, "enter=Enter&username=webbot&password=sp1der3");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_COOKIESESSION, true);
curl_setopt($ch, CURLOPT_COOKIEJAR, 'cookie-name'); //could be empty, but cause problems on some hosts
curl_setopt($ch, CURLOPT_COOKIEFILE, '/var/www/ip4.x/file/tmp'); //could be empty, but cause problems on some hosts

echo getSessionTime(curl_exec($ch));
sleep(1);
echo getSessionTime(curl_exec($ch));
sleep(1);
echo getSessionTime(curl_exec($ch));
sleep(1);
echo getSessionTime(curl_exec($ch));
sleep(1);
echo getSessionTime(curl_exec($ch));
sleep(1);
echo getSessionTime(curl_exec($ch));

输出：

<br>
Your login is good for another 3600 seconds
<br>
Your login is good for another 3599 seconds
<br>
Your login is good for another 3597 seconds
<br>
Your login is good for another 3596 seconds
<br>
Your login is good for another 3595 seconds
<br>
Your login is good for another 3594 seconds