Using SOAP with the Google API

This example shows how to use the SOAP component to submit searches via the Google SOAP API.

Testing this example requires a valid license key, which is available for free from http://api.google.com/.

examples/google/google.h:

 /****************************************************************************
 **
 ** Copyright (C) 2003-2008 Trolltech ASA. All rights reserved.
 **
 ** This file is part of a Qt Solutions component.
 **
 ** Licensees holding a valid Qt Solutions License Agreement may use this
 ** file in accordance with the rights, responsibilities, and obligations
 ** contained therein. Please consult your licensing agreement or contact
 ** sales@trolltech.com if any conditions of this licensing are not clear
 ** to you.
 **
 ** Further information about Qt Solutions licensing is available at:
 ** http://www.trolltech.com/products/qt/addon/solutions/
 ** or by contacting info@trolltech.com.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/
 #ifndef GOOGLE_H_INCLUDED
 #define GOOGLE_H_INCLUDED
 #include <QtGui/QWidget>
 #include <qtsoap.h>

 class QLineEdit;
 class QTextBrowser;
 class QPushButton;

 class Google : public QWidget
 {
     Q_OBJECT
 public:
     Google(QWidget *parent = 0);

 private slots:
     void submitRequest();
     void getResponse();

 private:
     QtSoapHttpTransport http;

     QLineEdit *searchString;
     QLineEdit *googleKey;
     QTextBrowser *resultView;
     QPushButton *quitButton;
     QPushButton *searchButton;
     QString key;
 };

 #endif

examples/google/google.cpp:

 /****************************************************************************
 **
 ** Copyright (C) 2003-2008 Trolltech ASA. All rights reserved.
 **
 ** This file is part of a Qt Solutions component.
 **
 ** Licensees holding a valid Qt Solutions License Agreement may use this
 ** file in accordance with the rights, responsibilities, and obligations
 ** contained therein. Please consult your licensing agreement or contact
 ** sales@trolltech.com if any conditions of this licensing are not clear
 ** to you.
 **
 ** Further information about Qt Solutions licensing is available at:
 ** http://www.trolltech.com/products/qt/addon/solutions/
 ** or by contacting info@trolltech.com.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/
 #include <QtGui/QApplication>
 #include <QtGui/QMessageBox>
 #include <QtGui/QCursor>
 #include <QtCore/QFile>
 #include <QtGui/QLabel>
 #include <QtGui/QLineEdit>
 #include <QtGui/QTextBrowser>
 #include <QtGui/QLayout>
 #include <QtGui/QPushButton>
 #include "google.h"

 Google::Google(QWidget *parent)
     : QWidget(parent), http(this)
 {
     // Generate the GUI.
     quitButton = new QPushButton("&Quit", this);
     searchString = new QLineEdit(this);
     resultView = new QTextBrowser(this);
     QVBoxLayout *layout = new QVBoxLayout(this);

     QLabel *gLabel = new QLabel("Google Web APIs license key: ", this);
     googleKey = new QLineEdit(this);
     QHBoxLayout *topBar = new QHBoxLayout();
     topBar->addWidget(gLabel);
     topBar->addWidget(googleKey);
     layout->addLayout(topBar);

     QLabel *sLabel = new QLabel("Search string: ", this);
     QPushButton *searchButton = new QPushButton("Search!", this);
     QHBoxLayout *searchBar = new QHBoxLayout();
     searchBar->addWidget(sLabel);
     searchBar->addWidget(searchString);
     searchBar->addWidget(searchButton);
     layout->addLayout(searchBar);

     layout->addWidget(resultView);
     layout->addWidget(quitButton);

     // Connect signals to slots. Note the submitRequest() slots.
     connect(&http, SIGNAL(responseReady()), SLOT(getResponse()));
     connect(quitButton, SIGNAL(clicked()), SLOT(close()));
     connect(searchString, SIGNAL(returnPressed()), SLOT(submitRequest()));
     connect(searchButton, SIGNAL(clicked()), SLOT(submitRequest()));
     connect(googleKey, SIGNAL(returnPressed()), SLOT(submitRequest()));

     // Pressing enter should trigger a search, unless focus has been
     // explicitly moved.
     searchButton->setDefault(true);

     // Prepare to submit request.
     http.setAction("urn:GoogleSearchAction");
     http.setHost("api.google.com");
 }

 void Google::submitRequest()
 {
     // Check that the license key is set.
     if (googleKey->text() == "") {
         QMessageBox::warning(this, tr("Missing license key"),
                              tr("Please enter your Google Web APIs license key."
                                 " If you do not have one, you can visit<br>"
                                 " http://api.google.com/ and create a Google"
                                 " account to obtain a license key."));
         return;
     }

     // Check that we have a search string.
     if (searchString->text() == "") {
         QMessageBox::warning(this, tr("Missing search string"),
                              tr("Please enter a search string."));
         return;

     }

     // Generate request. Details about how to generate a proper
     // request are available from http://api.google.com/. The results
     // are always fetched as latin1 in this example, but this can be
     // easily changed (see the "ie" and "oe" arguments below).
     QtSoapMessage request;
     request.setMethod(QtSoapQName("doGoogleSearch", "urn:GoogleSearch"));
     request.addMethodArgument("key", "", googleKey->text());
     request.addMethodArgument("q", "", searchString->text());
     request.addMethodArgument("start", "", 0);
     request.addMethodArgument("maxResults", "", 10);
     request.addMethodArgument("filter", "", false, 0);
     request.addMethodArgument("restrict", "", "");
     request.addMethodArgument("safeSearch", "", false, 0);
     request.addMethodArgument("lr", "", "");
     request.addMethodArgument("ie", "", "latin1");
     request.addMethodArgument("oe", "", "latin1");

     // Submit the method request to the web service.
     http.submitRequest(request, "/search/beta2");

     // Set the cursor to wait mode.
     QApplication::setOverrideCursor(QCursor(Qt::WaitCursor));
 }

 void Google::getResponse()
 {
     // Set cursor back to normal shape.
     QApplication::restoreOverrideCursor();

     // Reset resultView.
     resultView->clear();

     // Get the response, check for error.
     const QtSoapMessage &resp = http.getResponse();
     if (resp.isFault()) {
         resultView->setHtml(tr("<b>Query failed</b>: ")
                             + resp.faultString().value().toString());
         return;
     }

     // Extract the return value from this method response, check for
     // errors.
     const QtSoapType &res = resp.returnValue();
     if (!res.isValid()) {
         resultView->append(tr("Invalid return value"));
         return;
     }

     // Generate resultView output. Make it resemble the actual web
     // output from http://www.google.com/.
     QString header(tr("Searched the web for <b>%1</b>, results %2 - %3 "
                       "of about %4. Search took %5 seconds.<br><hr>")
                    .arg(res["searchQuery"].toString())
                    .arg(res["startIndex"].toInt())
                    .arg(res["endIndex"].toInt())
                    .arg(res["estimatedTotalResultsCount"].toInt())
                    .arg(res["searchTime"].value().toDouble(), 0, 'f', 2));

     const QtSoapType &resultElements = res["resultElements"];
     QString allElements;

     for (int i = 0; i < resultElements.count(); ++i) {
         const QtSoapType &resultElement = res["resultElements"][i];

         QString cat = resultElement["directoryCategory"]["fullViewableName"].toString();
         QString summary = resultElement["summary"].toString();
         QString title = resultElement["title"].toString();
         QString snippet = resultElement["snippet"].toString();
         QString url = resultElement["URL"].toString();
         QString cachedSize = resultElement["cachedSize"].toString();

         QString thisElement = "<br>";

         if (!title.isEmpty()) {
             thisElement += "<font color=\"#0000FF\"><b><u>"
                            + title + "</u></b></font><br>";
         } else {
             thisElement += "<font color=\"#0000FF\"><b><u>"
                            + url + "</u></b></font><br>";
         }

         if (!snippet.isEmpty())
             thisElement += snippet + "<br>";

         if (!summary.isEmpty()) {
             thisElement += "<font color=\"#808080\">Description:</font> "
                            + summary + "<br>";
         }

         if (!cat.isEmpty()) {
             thisElement += "<font color=\"#808080\">Category: <u>"
                            + cat + "</u></font><br>";
         }

         if (!title.isEmpty()) {
             thisElement += "<font color=\"#008000\"><u>" + url
                            + "</u> - " + cachedSize + "</font><br>";
         }

         allElements += thisElement;
     }

     // Update the resultView.
     resultView->setHtml(header + allElements);
 }

examples/google/main.cpp:

 /****************************************************************************
 **
 ** Copyright (C) 2003-2008 Trolltech ASA. All rights reserved.
 **
 ** This file is part of a Qt Solutions component.
 **
 ** Licensees holding a valid Qt Solutions License Agreement may use this
 ** file in accordance with the rights, responsibilities, and obligations
 ** contained therein. Please consult your licensing agreement or contact
 ** sales@trolltech.com if any conditions of this licensing are not clear
 ** to you.
 **
 ** Further information about Qt Solutions licensing is available at:
 ** http://www.trolltech.com/products/qt/addon/solutions/
 ** or by contacting info@trolltech.com.
 **
 ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
 ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 **
 ****************************************************************************/
 #include <QtGui/QApplication>
 #include "google.h"

 int main(int argc, char **argv)
 {
     QApplication app(argc, argv);

     Google google;

     google.show();

     return app.exec();
 }

examples/google/google.pro:

 TEMPLATE = app
 INCLUDEPATH += .
 CONFIG += debug

 include(../../src/qtsoap.pri)

 # Input
 HEADERS += google.h
 SOURCES += google.cpp main.cpp

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