5

我正在尝试使用 Reddit API 来做一些事情。除了更改页面和登录之外，我一切正常。

我需要登录才能使用我的程序，我知道如何使用我得到的 cookie，但我就是无法登录。

这是代码：

public static Login POST(URL url, String user, String pw) throws IOException
{

    String encodedData =  URLEncoder.encode("api_type=json&user=" + user +"&passwd="+pw, "UTF-8");
    HttpURLConnection ycConnection = null;
    ycConnection = (HttpURLConnection) url.openConnection();
    ycConnection.setRequestMethod("POST");
    ycConnection.setDoOutput(true);
    ycConnection.setUseCaches (false);
    ycConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
    PrintWriter out = new PrintWriter(ycConnection.getOutputStream());


    out.print(encodedData.getBytes());
    out.close();

    BufferedReader in = new BufferedReader(new InputStreamReader(ycConnection.getInputStream()));
    String response = in.readLine();

    Map<String, List<String>> headers = ycConnection.getHeaderFields(); 
    List<String> values = headers.get("Set-Cookie"); 
    String cookieValue = null; 
    for (java.util.Iterator<String> iter = values.iterator(); iter.hasNext(); ) {
         String v = iter.next(); 
         if (cookieValue == null)
             cookieValue = v;
         else
             cookieValue = cookieValue + ";" + v;
    }

    return new Login(cookieValue, response);
}

我得到的最典型的例外是：

java.io.IOException：服务器返回 HTTP 响应代码：URL 504：http ://www.reddit.com/api/login/kagnito/ at sun.net.www.protocol.http.HttpURLConnection.getInputStream（未知来源）

但我也收到了很多“无效密码”的消息。

我该如何解决这个问题？坚持了几个小时！

顺便提一句。这就是我无法理解的内容：https ://github.com/reddit/reddit/wiki/API%3A-login 我不知道如何发布这个？它应该进入标题，还是？我对 HTTP 协议不是很熟悉。（因此我的项目 - 我正在学习）

4

1 回答 1

11

如果不深入研究为什么其余部分可能不起作用，那么您会遇到一个问题：

  • 用于对您的帖子URLEncoder数据进行编码：您的帖子数据不会进入 URL，因此不要对其进行编码。

  • 您没有设置Content-Length标题。

这是您应该开始的：

public static Login POST(URL url, String user, String pw) throws IOException
{

    String data=  "api_type=json&user=" + user +"&passwd="+pw;
    HttpURLConnection ycConnection = null;
    ycConnection = (HttpURLConnection) url.openConnection();
    ycConnection.setRequestMethod("POST");
    ycConnection.setDoOutput(true);
    ycConnection.setUseCaches (false);
    ycConnection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
    ycConnection.setRequestProperty("Content-Length", data.length());

    PrintWriter out = new PrintWriter(ycConnection.getOutputStream());


    out.print(data.getBytes());
    out.close();

    BufferedReader in = new BufferedReader(new InputStreamReader(ycConnection.getInputStream()));
    String response = in.readLine();

    Map<String, List<String>> headers = ycConnection.getHeaderFields(); 
    List<String> values = headers.get("Set-Cookie"); 
    String cookieValue = null; 
    for (java.util.Iterator<String> iter = values.iterator(); iter.hasNext(); ) {
         String v = iter.next(); 
         if (cookieValue == null)
             cookieValue = v;
         else
             cookieValue = cookieValue + ";" + v;
    }

    return new Login(cookieValue, response);
}

当使用这样的 API 时，您应该明确地安装Fiddler，它是 HTTP 调试器。您会立即看到问题，因为您的帖子数据看起来与示例完全不同。

更新：

这是我刚刚投入测试的一小段代码，它对我进行了很好的验证（显然更改myusername为mypassword您的（不要忘记在 URL 中也进行更改）：

    @Test
    public void someTest() throws IOException
    {
        URL u = new URL( "https://ssl.reddit.com/api/login/myusername" );
        login( u, "myusername", "mypassword" );
    }

    public static void login( URL url, String user, String pw ) throws IOException
    {

        String data = "api_type=json&user=" + user + "&passwd=" + pw;
        HttpURLConnection ycConnection = null;
        ycConnection = ( HttpURLConnection ) url.openConnection();
        ycConnection.setRequestMethod( "POST" );
        ycConnection.setDoOutput( true );
        ycConnection.setUseCaches( false );
        ycConnection.setRequestProperty( "Content-Type",
            "application/x-www-form-urlencoded; charset=UTF-8" );
        ycConnection.setRequestProperty( "Content-Length", String.valueOf( data.length() ) );

        DataOutputStream wr = new DataOutputStream(
            ycConnection.getOutputStream() );
        wr.writeBytes( data );
        wr.flush();
        wr.close();
        InputStream is = ycConnection.getInputStream();
        BufferedReader rd = new BufferedReader( new InputStreamReader( is ) );
        String line;
        StringBuffer response = new StringBuffer();
        while ( ( line = rd.readLine() ) != null )
        {
            response.append( line );
            response.append( '\r' );
        }
        for ( Entry< String, List< String >> r : ycConnection.getHeaderFields().entrySet() )
        {
            System.out.println( r.getKey() + ": " + r.getValue() );
        }
        rd.close();
        System.out.println( response.toString() );
    }
于 2011-11-14T03:31:44.963 回答