Waiting for readyread and requestfinished signal

[srohit24]

I am building a app that contacts the server for data, gets it and then does some processing before displaying the result.

I have created a mapping function that maps all the functions that need to be called if a particular request has to be successful.

This code is the main part where all the calling is done.

if (check_if_clientID_is_present())
         call = "teci.create.client";
     qDebug() << "call"<< call;
 
     if(!call.isEmpty() && API_Request_Pointer == false)
         mapping(call);

if (check_if_clientID_is_present())
         call = "teci.create.client";
     qDebug() << "call"<< call;

     if(!call.isEmpty() && API_Request_Pointer == false)
         mapping(call);

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This is the mapping code where the required functions are called.
First i prepare the xml document, call the fetch function, then wait for the readyread and requestfinished signals, then call the parsing function and then exit the mapping function

void MainWindow::mapping(QString callname)
 {
     qDebug() <<"in mapping";
     QThread thread;
     if(call.compare("teci.create.client",callname)== 0)
     {
         qDebug() <<"inside create client";
         API_Request_Pointer = true;
         create_client();
         fetch();
         connect(&http, SIGNAL(readyRead(const QHttpResponseHeader &)),
              this, SLOT(readData(const QHttpResponseHeader &)));
 
         connect(&http, SIGNAL(requestFinished(int, bool)),
              this, SLOT(finished(int, bool)));
         parse_create_client();
         API_Request_Pointer = false;
         qDebug() <<"leaving create client";
     }
     else if (call.compare("teci.test.reverse",callname)== 0)
     {
        API_Request_Pointer = true;
        reverse_string();
        fetch();
        connect(&http, SIGNAL(readyRead(const QHttpResponseHeader &)),
              this, SLOT(readData(const QHttpResponseHeader &)));
 
        connect(&http, SIGNAL(requestFinished(int, bool)),
              this, SLOT(finished(int, bool)));
        parse_reverse_string();
        API_Request_Pointer = false;
     }
     qDebug() <<"leaving mapping";
 
 }

void MainWindow::mapping(QString callname)
 {
     qDebug() <<"in mapping";
     QThread thread;
     if(call.compare("teci.create.client",callname)== 0)
     {
         qDebug() <<"inside create client";
         API_Request_Pointer = true;
         create_client();
         fetch();
         connect(&http, SIGNAL(readyRead(const QHttpResponseHeader &)),
              this, SLOT(readData(const QHttpResponseHeader &)));

         connect(&http, SIGNAL(requestFinished(int, bool)),
              this, SLOT(finished(int, bool)));
         parse_create_client();
         API_Request_Pointer = false;
         qDebug() <<"leaving create client";
     }
     else if (call.compare("teci.test.reverse",callname)== 0)
     {
        API_Request_Pointer = true;
        reverse_string();
        fetch();
        connect(&http, SIGNAL(readyRead(const QHttpResponseHeader &)),
              this, SLOT(readData(const QHttpResponseHeader &)));

        connect(&http, SIGNAL(requestFinished(int, bool)),
              this, SLOT(finished(int, bool)));
        parse_reverse_string();
        API_Request_Pointer = false;
     }
     qDebug() <<"leaving mapping";

 }

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void MainWindow::fetch()
 {
 
     xml.clear();
 
     QByteArray string ("username");
     string.append(":");
     string.append("12345");
     QString encoded = string.toBase64();
     qDebug() <<"String"<< string <<"Encoded" <<encoded ;
 
     QUrl url("http://..../");
     url.setUserName("username");
     url.setPassword("12345");
 
     QHttpRequestHeader header("POST","/api/");
     header.setValue("Host",url.host());
     header.setValue("Path",url.path());
     header.setValue("Authorization","Basic " + encoded);
 
     http.setHost(url.host(),url.port(80));
 
     connectionId = http.request(header,xmlrequest);
     qDebug() << "Leaving fetch";
 }

void MainWindow::fetch()
 {

     xml.clear();

     QByteArray string ("username");
     string.append(":");
     string.append("12345");
     QString encoded = string.toBase64();
     qDebug() <<"String"<< string <<"Encoded" <<encoded ;

     QUrl url("http://..../");
     url.setUserName("username");
     url.setPassword("12345");

     QHttpRequestHeader header("POST","/api/");
     header.setValue("Host",url.host());
     header.setValue("Path",url.path());
     header.setValue("Authorization","Basic " + encoded);

     http.setHost(url.host(),url.port(80));

     connectionId = http.request(header,xmlrequest);
     qDebug() << "Leaving fetch";
 }

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void MainWindow::create_client()
 {
        here i add tags and create the xml 
 
        xmlrequest.append(doc.toString());
        qDebug() << xmlrequest.data();

void MainWindow::create_client()
 {
        here i add tags and create the xml 

        xmlrequest.append(doc.toString());
        qDebug() << xmlrequest.data();

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void MainWindow::readData(const QHttpResponseHeader &resp)
 {
 
 
     if (resp.statusCode() != 200)
         http.abort();
     else
     {
         xml.addData(http.readAll());
     }
      qDebug() << "Leaving readdata";
 }

void MainWindow::readData(const QHttpResponseHeader &resp)
 {
    

     if (resp.statusCode() != 200)
         http.abort();
     else
     {
         xml.addData(http.readAll());
     }
      qDebug() << "Leaving readdata";
 }

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void MainWindow::finished(int id, bool error)
 {
     qDebug() <<"Error" <<http.errorString();
     if (error) 
         qWarning("Received error during HTTP fetch.");
 
           qDebug() << "Leaving finished";
 }

void MainWindow::finished(int id, bool error)
 {
     qDebug() <<"Error" <<http.errorString();
     if (error) 
         qWarning("Received error during HTTP fetch.");

           qDebug() << "Leaving finished";
 }

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void MainWindow::parse_create_client()
 {
    qDebug() <<"Entering parser";
     while (!xml.atEnd())
     {
         xml.readNext();
         qDebug()<<xml.readNext();
         if (xml.isStartElement())
         {
             currentTag = xml.name().toString();
 
             if (currentTag == "client")
                 API_key += xml.attributes().value("key").toString();
             qDebug() << "CurrentTag"<<currentTag;
 
         }
 
         else if (xml.isCharacters() && !xml.isWhitespace())
         {
 
             if (currentTag == "password")
                 API_password += xml.text().toString();
         }
     }
 
    qDebug() << "webiste_clientID"<< API_key;
    qDebug() << "webiste_serial no"<<API_password;
 
      }
 }

void MainWindow::parse_create_client()
 {
    qDebug() <<"Entering parser";
     while (!xml.atEnd())
     {
         xml.readNext();
         qDebug()<<xml.readNext();
         if (xml.isStartElement())
         {
             currentTag = xml.name().toString();

             if (currentTag == "client")
                 API_key += xml.attributes().value("key").toString();
             qDebug() << "CurrentTag"<<currentTag;

         }
         
         else if (xml.isCharacters() && !xml.isWhitespace())
         {

             if (currentTag == "password")
                 API_password += xml.text().toString();
         }
     }

    qDebug() << "webiste_clientID"<< API_key;
    qDebug() << "webiste_serial no"<<API_password;

      }
 }

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After reading the data, i write it down in a file.

This is the output i am getting.

Getting data from the webiste 
call "teci.create.client" 
in mapping 
inside create client 
<request version="0.1" >
 <call name="teci.client.create" >
  <client>
   <kind>MOBILE</kind>
   <name>API Test suite 7001</name>
  </client>
 </call>
</request>
 
Leaving fetch 
Entering parser 
1 
webiste_clientID "" 
webiste_serial no "" 
leaving create client 
leaving mapping 
Leaving finished 
Leaving readdata

Getting data from the webiste 
call "teci.create.client" 
in mapping 
inside create client 
<request version="0.1" >
 <call name="teci.client.create" >
  <client>
   <kind>MOBILE</kind>
   <name>API Test suite 7001</name>
  </client>
 </call>
</request>
 
Leaving fetch 
Entering parser 
1 
webiste_clientID "" 
webiste_serial no "" 
leaving create client 
leaving mapping 
Leaving finished 
Leaving readdata

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the readyread and requestfinished signals are being called after the parsing function has been called.

How can i wait for the signal and then call the parsing function??

[wysota]

Either use waitForReadyRead() or call the parsing method from a slot connected to both signals you are waiting for where you will check if you received both of them or read this article [wiki]Keeping the GUI Responsive[/wiki].

[srohit24]

can u please gimme the code to wait for both the signals at the same time?

[wysota]

No, I can't. But you can read the article and write it yourself

Of course if you posted in the newbie section of the forum, I might have helped you a bit more but since you don't consider yourself a newbie, I'm sure your skills are enough to transform the code properly.

[nish]

can u please gimme the code to wait for both the signals at the same time?

rohit bhai.. this thing does not work anywhere.

[wysota]

can u please gimme the code to wait for both the signals at the same time?

Actually I can give you the code. But only if you give me your salary (or equivalent) for writing the application. I don't think that's worth it, is it?

[nish]

Actually I can give you the code. But only if you give me your salary (or equivalent) for writing the application. I don't think that's worth it, is it?

cool man cool down . he got enough.

[srohit24]

i would have given u my salary but i am not working for anyone nor earning a salary.

i am just working in Qt to complete a project for this semester.

I have had a lot of help from this forum, so got a bit carried away

Anyway, any hints or clue to complete this particular task huh?

[wysota]

i would have given u my salary but i am not working for anyone nor earning a salary.

i am just working in Qt to complete a project for this semester.

So maybe a salary for all the projects you will ever participate in thanks to the education you are going to receive?

I have had a lot of help from this forum, so got a bit carried away

Anyway, any hints or clue to complete this particular task huh?

Please read the article I pointed you to. Then use QEventLoop or move your parsing code to another method which will be called when both signals are flagged as received.

[srohit24]

If u really wanted returns for your help, in cash, you wouldnt be helping others out, almost every day in this forum

I split the creating and parsing xml into two parts.

I am calling the creating b4 fetch and then parsing it in the readData fucntion

void RSSListing::readData(const QHttpResponseHeader &resp)
 {
 
 
     if (resp.statusCode() != 200)
         http.abort();
     else
     {
         xml.addData(http.readAll());
         if(call.compare("teci.create.client",call)== 0)
         {
             qDebug() <<"inside parse create client";
             parse_create_client();
             API_Request_Pointer = false;
 
         }
         else if (call.compare("teci.test.reverse",call)== 0)
         {
            qDebug() << "Enter parse string reverse";
            parse_reverse_string();
            API_Request_Pointer = false;
         }
     }

void RSSListing::readData(const QHttpResponseHeader &resp)
 {
    

     if (resp.statusCode() != 200)
         http.abort();
     else
     {
         xml.addData(http.readAll());
         if(call.compare("teci.create.client",call)== 0)
         {
             qDebug() <<"inside parse create client";
             parse_create_client();
             API_Request_Pointer = false;

         }
         else if (call.compare("teci.test.reverse",call)== 0)
         {
            qDebug() << "Enter parse string reverse";
            parse_reverse_string();
            API_Request_Pointer = false;
         }
     }

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[wysota]

If u really wanted returns for your help, in cash, you wouldnt be helping others out, almost every day in this forum

Damn... you got me figured out...