在 Qt 中发送 SOAP 请求时的 ProtocolUnknownError

Posted 2023-02-16

【中文标题】在 Qt 中发送 SOAP 请求时的 ProtocolUnknownError

【英文标题】：ProtocolUnknownError upon sending SOAP request in Qt

【发布时间】：2017-11-06 06:08:25

【问题描述】：

我正在做一个在 Qt 中发送 SOAP 请求的简单示例。尝试是使用 QNetwork 资源并发送 SOAP 请求来获取某个国家/地区的城市。

http://www.webservicex.net/globalweather.asmx?op=GetCitiesByCountry.

请帮忙；错过了什么。感谢任何指针/输入。

构建机器 - Linux Debian

Qt 版本 - 5.7

SSL - 1.0.2 可用。

qDebug() << "Support SSL:  " << QSslSocket::supportsSsl()
         << "\nLib Version Number: " << QSslSocket::sslLibraryVersionNumber()
         << "\nLib Version String: " << QSslSocket::sslLibraryVersionString()
         << "\nLib Build Version Number: " << QSslSocket::sslLibraryBuildVersionNumber()
         << "\nLib Build Version String: " << QSslSocket::sslLibraryBuildVersionString();

输出

Support SSL:   true 
Lib Version Number:  268443855 
Lib Version String:  "OpenSSL 1.0.2l  25 May 2017" 
Lib Build Version Number:  268439647 
Lib Build Version String:  "OpenSSL 1.0.1e-fips 11 Feb 2013"

运行代码时出错

Network error:  QNetworkReply::NetworkError(ProtocolUnknownError)

代码

#include <QObject>
#include <QtNetwork>
#include <QNetworkAccessManager>
#include <QNetworkRequest>
#include <QNetworkReply>

int main(int argc, char *argv[])

    QCoreApplication app(argc, argv);

    QNetworkAccessManager manager;

    QNetworkRequest request;

    //Set SOAP headers

    request.setRawHeader("POST", "/globalweather.asmx HTTP/1.1");
    request.setRawHeader("Content-Type", "text/xml;charset=UTF-8");
    request.setRawHeader("Content-Length", "1024");
    request.setRawHeader("SOAPAction", "http://www.webserviceX.NET/GetCitiesByCountry");
    //request.setRawHeader("Host", "www.webservicex.net");
    request.setUrl(QUrl("www.webservicex.net"));


    // Prepare SOAP request XML

    QString query =
    "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
    "<soap:Envelope xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\" xmlns:soap=\"http://schemas.xmlsoap.org/soap/envelope/\">"
    "<soap:Body>"
    "<GetCitiesByCountry xmlns=\"http://www.webserviceX.NET\">"
    "<CountryName>Australia</CountryName>"
    "</GetCitiesByCountry>"
    "</soap:Body>"
    "</soap:Envelope>";

    QNetworkReply* reply = manager.post(request, query.toUtf8());

    QEventLoop eventLoop;

    QObject::connect(reply, SIGNAL(finished()), &eventLoop, SLOT(quit()));
    eventLoop.exec();

    if (reply->error() != QNetworkReply::NoError)    
        qDebug() << "Network error: " << reply->error();
    else    
        qDebug() << reply->readAll();    

    return app.exec();
 

引用的资源

http://www.qtcentre.org/threads/29856-sending-soap-request-using-QNetworkAccessManager-question

https://evileg.com/en/post/233/

Qt Web Service post query

Sending HTTP Header Info with Qt QNetworkAccessManager

Sending an HTTP request using QNetworkAccessManager

https://en.wikipedia.org/wiki/List_of_HTTP_header_fields

【问题讨论】：

在这里使用 Wireshark 可以准确了解 Qt 发送到服务器的内容。也就是说，SOAP 已经有将近二十年的历史了。现代代码应该使用 RESTful Web API。

【参考方案1】：

调用manager.post(request, query.toUtf8()); 将覆盖您的request.setRawHeader("POST", "/globalweather.asmx HTTP/1.1");

如果您想使用自定义标题等，请使用sendCustomRequest

或者在QNetworkRequest中设置正确的Uri，并在QNetworkAccessManager::post方法中使用这个请求。

    //request.setRawHeader("POST", "/globalweather.asmx HTTP/1.1");
    request.setRawHeader("Content-Type", "text/xml;charset=UTF-8");
    request.setRawHeader("Content-Length", "1024");
    request.setRawHeader("SOAPAction", "http://www.webserviceX.NET/GetCitiesByCountry");
    //request.setRawHeader("Host", "www.webservicex.net");
    request.setUrl(QUrl("http://www.webservicex.net/globalweather.asmx"));