我用
Java编写了一个HTTP服务器,用Poco编写了一个C语言的客户端.这是C客户端代码的一部分:
URI uri("http://127.0.0.1:4444");
HTTPClientSession session(uri.getHost(), uri.getPort());
HTTPRequest req(HTTPRequest::HTTP_POST,
"/pages/page",
HTTPMessage::HTTP_1_1);
session.sendRequest(req);
HTTPResponse res;
std::istream &is = session.receiveResponse(res);
在最后一行,我收到以下错误:
terminate called after throwing an instance of 'Poco::Net::NoMessageException'
what(): No message received
但我不明白为什么.连接已成功建立,并且请求的页面存在.我尝试了与已知网站(如维基百科)相同的代码,它没有任何例外.
我还尝试在命令行中使用cURL(到我的服务器)发出完全相同的请求,它显示服务器的响应,因此服务器看起来很好.
这是服务器以字符串形式的原始响应:
"HTTP/1.1 200 OK\r\n" +
"Server: [server name]\r\n" +
"Content-Type: text/xml; charset=utf-8\r\n" +
"Content-Length:" + bodyBytes.length + "\r\n" +
"Resource: " + job.resId + "\r\n\r\n" +
"<?xml version=\"1.0\" encoding=\"UTF-8\"?><JobRequest><InputRepresentation id=\"0\"/> <effectsList><cvtColor><code> CV_RGB2GRAY </code></cvtColor><resize><scaleFactorX> 0.5 </scaleFactorX><scaleFactorY> 0.5 </scaleFactorY><interpolation> INTER_LINEAR </interpolation></resize><GaussianBlur><kSize> 3 </kSize><sigmaX> 2 </sigmaX><sigmaY> 2 </sigmaY><borderType> BORDER_REPLICATE </borderType></GaussianBlur></effectsList></JobRequest>"
我编写了一个简单的HTTP服务器,它响应每个请求的固定响应,以测试出错的地方.这是代码:
public class Test {
public static void main(String[] args) {
try {
ServerSocket serverSocket = new ServerSocket(4449);
Socket clientSocket = serverSocket.accept();
String body = "ab";
byte[] bodyBytes = body.getBytes("UTF-8");
String headers = "HTTP/1.1 200 OK\r\n" +
"Server: Foo\r\n" +
"Content-Type: text/plain\r\n" +
"Content-Length: " + bodyBytes.length + "\r\n\r\n";
byte[] headerBytes = headers.getBytes("UTF-8");
byte[] responseBytes = new byte[headerBytes.length + bodyBytes.length];
/* Fill responseBytes with the header and body bytes */
int i = 0;
for (int j = 0; j < headerBytes.length; ++j) {
responseBytes[i] = headerBytes[j];
++i;
}
for (int j = 0; j < bodyBytes.length; ++j) {
responseBytes[i] = bodyBytes[j];
++i;
}
clientSocket.getOutputStream().write(responseBytes);
} catch (IOException e) {}
}
}
即使使用此服务器,我也会得到相同的异常.那么这里有什么问题?
最佳答案 基于实验,我发现如果你发出一个空的POST请求,有必要包含一个Content-Length头.即,
req.add("Content-Length", "0");