QDS-11878 Reduce the numbers of user notification

• fix: QDS-11878 show only one error in case of network issue

src/backend.cpp

@@ -336,16 +336,16 @@ void Backend::runDemoProject(const QString &projectName)
 
     // sample project info
     // [{"lastUpdate":1701947766739.9812,"name":"ClusterTutorial.qmlrc"}]
-    const QJsonArray projectList = m_serviceConnector.fetchUserDemoList();
+    const std::optional<QJsonArray> projectList = m_serviceConnector.fetchUserDemoList();
 
-    if (projectList.isEmpty()) {
+    if (projectList == std::nullopt) {
         qCritical("Please check your internet connection and try again");
         emit popupClose();
         return;
     }
 
     QJsonObject projectInfo;
-    for (auto project : projectList) {
+    for (auto project : projectList.value()) {
         if (projectName == project.toObject().value("name").toString().remove(".qmlrc")) {
             projectInfo = project.toObject();
             break;
@@ -359,11 +359,19 @@ void Backend::runDemoProject(const QString &projectName)
 
         const QString url = "https://designviewer.qt.io/qmlprojects/demos/" + projectName
                             + ".qmlrc";
-        QByteArray project = m_serviceConnector.fetchProject(url);
+        const std::optional<QByteArray> project = m_serviceConnector.fetchProject(url);
+
+        if (project == std::nullopt) {
+            qCritical() << "Could not download demo project. Please check the logs for more "
+                           "information.";
+            emit popupClose();
+            return;
+        }
+
         qDebug() << "Demo project is not cached. Trying to download from " << url << " ...";
 
         updatePopup("Caching demo project...");
-        if (!m_projectManager->cacheDemoProject(project, projectInfo)) {
+        if (!m_projectManager->cacheDemoProject(project.value(), projectInfo)) {
             qCritical()
                 << "Could not cache demo project. Please check the logs for more information.";
             emit popupClose();
@@ -405,9 +413,9 @@ void Backend::runUserProject(const QString &projectName)
     const QString userHash = Backend::userHash();
 
     qDebug("Checking if project is cached. Getting list of available projects...");
-    const QJsonArray projectList = m_serviceConnector.fetchUserProjectList(userHash);
+    const std::optional<QJsonArray> projectList = m_serviceConnector.fetchUserProjectList(userHash);
 
-    if (projectList.isEmpty()) {
+    if (projectList == std::nullopt) {
         qCritical("Please check your internet connection and try again");
         emit popupClose();
         return;
@@ -416,7 +424,7 @@ void Backend::runUserProject(const QString &projectName)
     QString projectLastModified;
     QString projectId;
     QJsonObject projectInfo;
-    for (auto project : projectList) {
+    for (auto project : projectList.value()) {
         if (projectName == project.toObject().value("appName").toString()) {
             projectInfo = project.toObject();
             break;
@@ -428,10 +436,18 @@ void Backend::runUserProject(const QString &projectName)
     if (!projectCached) {
         qDebug("Project is not cached. Downloading...");
         updatePopup("Project is not cached. Downloading...", false);
-        QByteArray projectData = m_serviceConnector.fetchUserProject(userHash, projectName);
+        const std::optional<QByteArray> projectData
+            = m_serviceConnector.fetchUserProject(userHash, projectName);
+
+        if (projectData == std::nullopt) {
+            qCritical()
+                << "Could not download project. Please check the logs for more information.";
+            emit popupClose();
+            return;
+        }
 
         updatePopup("Caching user project...");
-        if (!m_projectManager->cacheProject(projectData, projectInfo)) {
+        if (!m_projectManager->cacheProject(projectData.value(), projectInfo)) {
             qCritical() << "Could not cache project. Please check the logs for more information.";
             emit popupClose();
             return;
@@ -455,14 +471,16 @@ void Backend::runOnlineProject(const QString &url)
     initializeProjectManager();
     emit popupOpen();
     updatePopup("Downloading...", false);
-    QByteArray projectData = m_serviceConnector.fetchProject(url);
-    if (projectData.isEmpty()) {
+    const std::optional<QByteArray> projectData = m_serviceConnector.fetchProject(url);
+
+    if (projectData == std::nullopt) {
         qCritical() << "Could not download project. Please check the logs for more information.";
+        emit popupClose();
         return;
     }
 
     updatePopup("Unpacking project...");
-    QString projectPath = m_projectManager->unpackProject(projectData);
+    QString projectPath = m_projectManager->unpackProject(projectData.value());
     updatePopup("Running project...");
 
     if (!m_projectManager->runProject(projectPath))
@@ -484,16 +502,16 @@ void Backend::updateUserProjectList()
     }
 
     qDebug() << "Fetching available project list for user:" << userHash;
-    QJsonArray projectList = m_serviceConnector.fetchUserProjectList(userHash);
+    const std::optional<QJsonArray> projectList = m_serviceConnector.fetchUserProjectList(userHash);
 
-    if (projectList == m_projectList) {
-        qDebug("No new projects are available");
-    } else if (projectList.isEmpty()) {
+    if (projectList == std::nullopt) {
         qWarning("Could not fetch project list. Either there are no projects or there is a "
                  "network issue");
+    } else if (projectList.value() == m_projectList) {
+        qDebug("No new projects are available");
     } else {
         qDebug("List of available projects fetched:");
-        for (const auto &project : projectList) {
+        for (const auto &project : projectList.value()) {
             const QString projectName{project.toObject().value("appName").toString()};
             qDebug() << "--" << projectName;
         }
@@ -502,7 +520,7 @@ void Backend::updateUserProjectList()
     // we need to set m_projectList even if it is empty
     // because this triggers the onModelChanged function in the QML
     // in order to update the UI
-    m_projectList = projectList;
+    m_projectList = projectList.value();
     emit projectListChanged();
 }