Handle redirections more nicely

* Log redirections in accordance with logging settings
* Load self-signed certificate as needed

syncthingconnector/syncthingconnection.cpp

@@ -778,13 +778,13 @@ void SyncthingConnection::continueConnecting()
  *    only do the cleanup of previous certificates but not emit any errors.
  * \returns Returns whether a certificate could be loaded.
  */
-bool SyncthingConnection::loadSelfSignedCertificate()
+bool SyncthingConnection::loadSelfSignedCertificate(const QUrl &url)
 {
     // ensure current exceptions for self-signed certificates are cleared
     m_expectedSslErrors.clear();
 
     // not required when not using secure connection
-    const QUrl syncthingUrl(m_syncthingUrl);
+    const auto syncthingUrl = url.isEmpty() ? m_syncthingUrl : url;
     if (!syncthingUrl.scheme().endsWith(QChar('s'))) {
         return false;
     }

syncthingconnector/syncthingconnection.h

@@ -180,7 +180,7 @@ public:
     const QList<QSslError> &expectedSslErrors() const;
 
 public Q_SLOTS:
-    bool loadSelfSignedCertificate();
+    bool loadSelfSignedCertificate(const QUrl &url = QUrl());
     bool applySettings(Data::SyncthingConnectionSettings &connectionSettings);
 
     // methods to initiate/close connection
@@ -337,6 +337,7 @@ private Q_SLOTS:
     void handleFatalConnectionError();
     void handleAdditionalRequestCanceled();
     void handleSslErrors(const QList<QSslError> &errors);
+    void handleRedirection(const QUrl &url);
     void recalculateStatus();
     QString configPath() const;
     QByteArray changeConfigVerb() const;

syncthingconnector/syncthingconnection_requests.cpp

@@ -63,6 +63,7 @@ QNetworkReply *SyncthingConnection::requestData(const QString &path, const QUrlQ
 #ifndef LIB_SYNCTHING_CONNECTOR_CONNECTION_MOCKED
     auto *const reply = networkAccessManager().get(prepareRequest(path, query, rest, longPolling));
     QObject::connect(reply, &QNetworkReply::sslErrors, this, &SyncthingConnection::handleSslErrors);
+    QObject::connect(reply, &QNetworkReply::redirected, this, &SyncthingConnection::handleRedirection);
     if (loggingFlags() & SyncthingConnectionLoggingFlags::ApiCalls) {
         cerr << Phrases::Info << "Querying API: GET " << reply->url().toString().toStdString() << Phrases::EndFlush;
     }
@@ -188,6 +189,24 @@ void SyncthingConnection::handleSslErrors(const QList<QSslError> &errors)
     }
 }
 
+/*!
+ * \brief Handles redirections.
+ * \remarks The redirect policy will decide whether to follow the redirection or not.
+ *          This function merely handles logging and loading the certificate in case this
+ *          hasn't happened before (e.g. a redirection from http to https).
+ */
+void SyncthingConnection::handleRedirection(const QUrl &url)
+{
+    if (m_loggingFlags & SyncthingConnectionLoggingFlags::ApiReplies) {
+        const auto urlStr = url.toString().toUtf8();
+        cerr << Phrases::Info << "Got redirected to: " << std::string_view(urlStr.data(), static_cast<std::string_view::size_type>(urlStr.size()))
+             << Phrases::EndFlush;
+    }
+    if (m_expectedSslErrors.isEmpty() && url.scheme().endsWith(QChar('s'))) {
+        loadSelfSignedCertificate(url);
+    }
+}
+
 /*!
  * \brief Handles the specified \a reply; invoked by the prepareReply() functions.
  */

syncthingconnector/tests/misctests.cpp

@@ -188,7 +188,7 @@ void MiscTests::testConnectionSettingsAndLoadingSelfSignedCert()
     bool errorOccured = false;
     const function<void(const QString &)> errorHandler
         = [&errorOccured](const QString &message) { errorOccured |= message == QStringLiteral("Unable to load certificate used by Syncthing."); };
-    waitForSignals(bind(&SyncthingConnection::loadSelfSignedCertificate, &connection), 1,
+    waitForSignals(bind(&SyncthingConnection::loadSelfSignedCertificate, &connection, QUrl()), 1,
         signalInfo(&connection, &SyncthingConnection::error, errorHandler, &errorOccured));
     settings.expectedSslErrors.clear();
     CPPUNIT_ASSERT(!connection.applySettings(settings));