qt5base-lts/examples/network/http/httpwindow.cpp

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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of The Qt Company Ltd nor the names of its
** contributors may be used to endorse or promote products derived
** from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtWidgets>
#include <QtNetwork>
#include <QUrl>
#include "httpwindow.h"
#include "ui_authenticationdialog.h"
#ifndef QT_NO_SSL
static const char defaultUrl[] = "https://qt-project.org/";
#else
static const char defaultUrl[] = "http://qt-project.org/";
#endif
static const char defaultFileName[] = "index.html";
ProgressDialog::ProgressDialog(const QUrl &url, QWidget *parent)
: QProgressDialog(parent)
{
setWindowTitle(tr("Download Progress"));
setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
setLabelText(tr("Downloading %1.").arg(url.toDisplayString()));
setMinimum(0);
setValue(0);
setMinimumDuration(0);
}
void ProgressDialog::networkReplyProgress(qint64 bytesRead, qint64 totalBytes)
{
setMaximum(totalBytes);
setValue(bytesRead);
}
HttpWindow::HttpWindow(QWidget *parent)
: QDialog(parent)
, statusLabel(new QLabel(tr("Please enter the URL of a file you want to download.\n\n"), this))
, urlLineEdit(new QLineEdit(defaultUrl))
, downloadButton(new QPushButton(tr("Download")))
, launchCheckBox(new QCheckBox("Launch file"))
, defaultFileLineEdit(new QLineEdit(defaultFileName))
, downloadDirectoryLineEdit(new QLineEdit)
, reply(Q_NULLPTR)
, file(Q_NULLPTR)
, httpRequestAborted(false)
{
setWindowFlags(windowFlags() & ~Qt::WindowContextHelpButtonHint);
setWindowTitle(tr("HTTP"));
connect(&qnam, &QNetworkAccessManager::authenticationRequired,
this, &HttpWindow::slotAuthenticationRequired);
#ifndef QT_NO_SSL
connect(&qnam, &QNetworkAccessManager::sslErrors,
this, &HttpWindow::sslErrors);
#endif
QFormLayout *formLayout = new QFormLayout;
urlLineEdit->setClearButtonEnabled(true);
connect(urlLineEdit, &QLineEdit::textChanged,
this, &HttpWindow::enableDownloadButton);
formLayout->addRow(tr("&URL:"), urlLineEdit);
QString downloadDirectory = QStandardPaths::writableLocation(QStandardPaths::DownloadLocation);
if (downloadDirectory.isEmpty() || !QFileInfo(downloadDirectory).isDir())
downloadDirectory = QDir::currentPath();
downloadDirectoryLineEdit->setText(QDir::toNativeSeparators(downloadDirectory));
formLayout->addRow(tr("&Download directory:"), downloadDirectoryLineEdit);
formLayout->addRow(tr("Default &file:"), defaultFileLineEdit);
launchCheckBox->setChecked(true);
formLayout->addRow(launchCheckBox);
QVBoxLayout *mainLayout = new QVBoxLayout(this);
mainLayout->addLayout(formLayout);
mainLayout->addItem(new QSpacerItem(0, 0, QSizePolicy::Ignored, QSizePolicy::MinimumExpanding));
statusLabel->setWordWrap(true);
mainLayout->addWidget(statusLabel);
downloadButton->setDefault(true);
connect(downloadButton, &QAbstractButton::clicked, this, &HttpWindow::downloadFile);
QPushButton *quitButton = new QPushButton(tr("Quit"));
quitButton->setAutoDefault(false);
connect(quitButton, &QAbstractButton::clicked, this, &QWidget::close);
QDialogButtonBox *buttonBox = new QDialogButtonBox;
buttonBox->addButton(downloadButton, QDialogButtonBox::ActionRole);
buttonBox->addButton(quitButton, QDialogButtonBox::RejectRole);
mainLayout->addWidget(buttonBox);
urlLineEdit->setFocus();
}
void HttpWindow::startRequest(const QUrl &requestedUrl)
{
url = requestedUrl;
httpRequestAborted = false;
reply = qnam.get(QNetworkRequest(url));
connect(reply, &QNetworkReply::finished, this, &HttpWindow::httpFinished);
connect(reply, &QIODevice::readyRead, this, &HttpWindow::httpReadyRead);
ProgressDialog *progressDialog = new ProgressDialog(url, this);
progressDialog->setAttribute(Qt::WA_DeleteOnClose);
connect(progressDialog, &QProgressDialog::canceled, this, &HttpWindow::cancelDownload);
connect(reply, &QNetworkReply::downloadProgress, progressDialog, &ProgressDialog::networkReplyProgress);
connect(reply, &QNetworkReply::finished, progressDialog, &ProgressDialog::hide);
progressDialog->show();
statusLabel->setText(tr("Downloading %1...").arg(url.toString()));
}
void HttpWindow::downloadFile()
{
const QString urlSpec = urlLineEdit->text().trimmed();
if (urlSpec.isEmpty())
return;
const QUrl newUrl = QUrl::fromUserInput(urlSpec);
if (!newUrl.isValid()) {
QMessageBox::information(this, tr("Error"),
tr("Invalid URL: %1: %2").arg(urlSpec, newUrl.errorString()));
return;
}
QString fileName = newUrl.fileName();
if (fileName.isEmpty())
fileName = defaultFileLineEdit->text().trimmed();
if (fileName.isEmpty())
fileName = defaultFileName;
QString downloadDirectory = QDir::cleanPath(downloadDirectoryLineEdit->text().trimmed());
if (!downloadDirectory.isEmpty() && QFileInfo(downloadDirectory).isDir())
fileName.prepend(downloadDirectory + '/');
if (QFile::exists(fileName)) {
if (QMessageBox::question(this, tr("Overwrite Existing File"),
tr("There already exists a file called %1 in "
"the current directory. Overwrite?").arg(fileName),
QMessageBox::Yes|QMessageBox::No, QMessageBox::No)
== QMessageBox::No)
return;
QFile::remove(fileName);
}
file = openFileForWrite(fileName);
if (!file)
return;
downloadButton->setEnabled(false);
// schedule the request
startRequest(newUrl);
}
QFile *HttpWindow::openFileForWrite(const QString &fileName)
{
QScopedPointer<QFile> file(new QFile(fileName));
if (!file->open(QIODevice::WriteOnly)) {
QMessageBox::information(this, tr("Error"),
tr("Unable to save the file %1: %2.")
.arg(QDir::toNativeSeparators(fileName),
file->errorString()));
return Q_NULLPTR;
}
return file.take();
}
void HttpWindow::cancelDownload()
{
statusLabel->setText(tr("Download canceled."));
httpRequestAborted = true;
reply->abort();
downloadButton->setEnabled(true);
}
void HttpWindow::httpFinished()
{
QFileInfo fi;
if (file) {
fi.setFile(file->fileName());
file->close();
delete file;
file = Q_NULLPTR;
}
if (httpRequestAborted) {
reply->deleteLater();
reply = Q_NULLPTR;
return;
}
if (reply->error()) {
QFile::remove(fi.absoluteFilePath());
statusLabel->setText(tr("Download failed:\n%1.").arg(reply->errorString()));
downloadButton->setEnabled(true);
reply->deleteLater();
reply = Q_NULLPTR;
return;
}
const QVariant redirectionTarget = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
reply->deleteLater();
reply = Q_NULLPTR;
if (!redirectionTarget.isNull()) {
const QUrl redirectedUrl = url.resolved(redirectionTarget.toUrl());
if (QMessageBox::question(this, tr("Redirect"),
tr("Redirect to %1 ?").arg(redirectedUrl.toString()),
QMessageBox::Yes | QMessageBox::No) == QMessageBox::No) {
downloadButton->setEnabled(true);
return;
}
file = openFileForWrite(fi.absoluteFilePath());
if (!file) {
downloadButton->setEnabled(true);
return;
}
startRequest(redirectedUrl);
return;
}
statusLabel->setText(tr("Downloaded %1 bytes to %2\nin\n%3")
.arg(fi.size()).arg(fi.fileName(), QDir::toNativeSeparators(fi.absolutePath())));
if (launchCheckBox->isChecked())
QDesktopServices::openUrl(QUrl::fromLocalFile(fi.absoluteFilePath()));
downloadButton->setEnabled(true);
}
void HttpWindow::httpReadyRead()
{
// this slot gets called every time the QNetworkReply has new data.
// We read all of its new data and write it into the file.
// That way we use less RAM than when reading it at the finished()
// signal of the QNetworkReply
if (file)
file->write(reply->readAll());
}
void HttpWindow::enableDownloadButton()
{
downloadButton->setEnabled(!urlLineEdit->text().isEmpty());
}
void HttpWindow::slotAuthenticationRequired(QNetworkReply*,QAuthenticator *authenticator)
{
QDialog authenticationDialog;
Ui::Dialog ui;
ui.setupUi(&authenticationDialog);
authenticationDialog.adjustSize();
ui.siteDescription->setText(tr("%1 at %2").arg(authenticator->realm(), url.host()));
// Did the URL have information? Fill the UI
// This is only relevant if the URL-supplied credentials were wrong
ui.userEdit->setText(url.userName());
ui.passwordEdit->setText(url.password());
if (authenticationDialog.exec() == QDialog::Accepted) {
authenticator->setUser(ui.userEdit->text());
authenticator->setPassword(ui.passwordEdit->text());
}
}
#ifndef QT_NO_SSL
void HttpWindow::sslErrors(QNetworkReply*,const QList<QSslError> &errors)
{
QString errorString;
foreach (const QSslError &error, errors) {
if (!errorString.isEmpty())
errorString += '\n';
errorString += error.errorString();
}
if (QMessageBox::warning(this, tr("SSL Errors"),
tr("One or more SSL errors has occurred:\n%1").arg(errorString),
QMessageBox::Ignore | QMessageBox::Abort) == QMessageBox::Ignore) {
reply->ignoreSslErrors();
}
}
#endif