Use non blocking passord reading

This also remove the do while loop that might cause problem and expose
the error message to the user.

Signed-off-by: Carl Schwan <carl@carlschwan.eu>

src/controller.cpp

@@ -262,7 +262,23 @@ void Controller::invokeLogin()
             id = accountId;
         }
         if (!account.homeserver().isEmpty()) {
-            auto accessToken = loadAccessTokenFromKeyChain(account);
+            auto accessTokenLoadingJob = loadAccessTokenFromKeyChain(account);
+            connect(accessTokenLoadingJob, &QKeychain::Job::finished, this, [accountId, id, this, accessTokenLoadingJob](QKeychain::Job *) {
+                AccountSettings account{accountId};
+                QString accessToken;
+                if (accessTokenLoadingJob->error() == QKeychain::Error::NoError) {
+                    accessToken = accessTokenLoadingJob->binaryData();
+                } else {
+                    // No access token from the keychain, try token file
+                    // TODO FIXME this code is racy since the file might have
+                    // already been removed. But since the other code do a blocking
+                    // dbus call, the probability are not high that it will happen.
+                    // loadAccessTokenFromFile is also mostly legacy nowadays
+                    accessToken = loadAccessTokenFromFile(account);
+                    if (accessToken.isEmpty()) {
+                        return;
+                    }
+                }
 
                 auto connection = new Connection(account.homeserver());
                 connect(connection, &Connection::connected, this, [this, connection, id] {
@@ -287,6 +303,7 @@ void Controller::invokeLogin()
                     Q_EMIT errorOccured(i18n("Network Error: %1", error));
                 });
                 connection->assumeIdentity(account.userId(), accessToken, account.deviceId());
+            });
         }
     }
     if (accounts.isEmpty()) {
@@ -309,32 +326,17 @@ QByteArray Controller::loadAccessTokenFromFile(const AccountSettings &account)
     return {};
 }
 
-QByteArray Controller::loadAccessTokenFromKeyChain(const AccountSettings &account)
+QKeychain::ReadPasswordJob *Controller::loadAccessTokenFromKeyChain(const AccountSettings &account)
 {
-    QKeychain::Error error;
-    QString errorString;
-    do {
     qDebug() << "Reading access token from the keychain for" << account.userId();
-        QKeychain::ReadPasswordJob job(qAppName());
+    auto job = new QKeychain::ReadPasswordJob(qAppName(), this);
-        job.setAutoDelete(false);
+    job->setKey(account.userId());
-        job.setKey(account.userId());
-        QEventLoop loop;
-        QKeychain::ReadPasswordJob::connect(&job, &QKeychain::Job::finished, &loop, &QEventLoop::quit);
-        job.start();
-        loop.exec();
 
-        if (job.error() == QKeychain::Error::NoError) {
+    // Handling of errors
-            return job.binaryData();
+    connect(job, &QKeychain::Job::emitFinishedWithError, this, [this, &account, job](QKeychain::Error error, const QString &errorString) {
-        }
+        if (error == QKeychain::Error::EntryNotFound) {
-        Q_EMIT globalErrorOccured(i18n("Unable to read access token"), i18n("Please make sure that the keychain is opened."));
-        error = job.error();
-        errorString = job.errorString();
-    } while (error == QKeychain::Error::OtherError);
-
-    qWarning() << "Could not read the access token from the keychain:" << errorString;
             // no access token from the keychain, try token file
             auto accessToken = loadAccessTokenFromFile(account);
-    if (error == QKeychain::Error::EntryNotFound) {
             if (!accessToken.isEmpty()) {
                 qDebug() << "Migrating the access token from file to the keychain for " << account.userId();
                 bool removed = false;
@@ -347,10 +349,31 @@ QByteArray Controller::loadAccessTokenFromKeyChain(const AccountSettings &accoun
                     qDebug() << "Migrating the access token from the file to the keychain "
                                 "failed";
                 }
+                return;
             }
         }
 
-    return accessToken;
+        switch (error) {
+        case QKeychain::EntryNotFound:
+            Q_EMIT globalErrorOccured(i18n("Access token wasn't found"), i18n("Maybe it was deleted?"));
+            break;
+        case QKeychain::AccessDeniedByUser:
+        case QKeychain::AccessDenied:
+            Q_EMIT globalErrorOccured(i18n("Access to keychain was denied."), i18n("Please allow NeoChat to read the access token"));
+            break;
+        case QKeychain::NoBackendAvailable:
+            Q_EMIT globalErrorOccured(i18n("No keychain available."), i18n("Please install a keychain, e.g. KWallet or GNOME keyring on Linux"));
+            break;
+        case QKeychain::OtherError:
+            Q_EMIT globalErrorOccured(i18n("Unable to read access token"), errorString);
+            break;
+        default:
+            break;
+        }
+    });
+    job->start();
+
+    return job;
 }
 
 bool Controller::saveAccessTokenToFile(const AccountSettings &account, const QByteArray &accessToken)

src/controller.h

@@ -23,6 +23,11 @@ class NeoChatRoom;
 class NeoChatUser;
 class QQuickWindow;
 
+namespace QKeychain
+{
+class ReadPasswordJob;
+}
+
 using namespace Quotient;
 
 class Controller : public QObject
@@ -99,7 +104,7 @@ private:
     bool m_busy = false;
 
     static QByteArray loadAccessTokenFromFile(const AccountSettings &account);
-    QByteArray loadAccessTokenFromKeyChain(const AccountSettings &account);
+    QKeychain::ReadPasswordJob *loadAccessTokenFromKeyChain(const AccountSettings &account);
 
     void loadSettings();
     void saveSettings() const;