Have the runtime check in a loop to see if the app server is up before

opening the browser window.

runtime/BrowserWindow.cpp

@@ -32,10 +32,9 @@
 
 
 // Constructor
-BrowserWindow::BrowserWindow(quint16 port)
+BrowserWindow::BrowserWindow(QString url)
 {
-    // Setup the URL the browser will connect to
-    m_appServerUrl = QString("http://localhost:%1").arg(port);
+    m_appServerUrl = url;
 
     // Setup the UI
     createActions();
@@ -54,7 +53,7 @@ BrowserWindow::BrowserWindow(quint16 port)
     // Display the app
     m_initialLoad = true;
     m_loadAttempt = 1;
-    webView->setUrl(QString("http://localhost/:%1").arg(9876));
+    webView->setUrl(m_appServerUrl);
 }
 
 

runtime/BrowserWindow.h

@@ -34,7 +34,7 @@ class BrowserWindow : public QMainWindow
     Q_OBJECT
 
 public:
-    BrowserWindow(quint16 port);
+    BrowserWindow(QString url);
 
 protected:
     void closeEvent(QCloseEvent *event);

runtime/Server.cpp

@@ -60,7 +60,7 @@ bool Server::Init()
 
     if (!QFile::exists(m_appfile))
     {
-	setError("Failed to locate pgAdmin4.py, terminating server thread.");
+        setError(tr("Failed to locate pgAdmin4.py, terminating server thread."));
         return false;
     }
 
@@ -73,7 +73,7 @@ void Server::run()
     FILE *cp = fopen(m_appfile.toUtf8().data(), "r");
     if (!cp)
     {
-        setError("Failed to open the application file: " + m_appfile + ", server thread exiting.");
+        setError(QString(tr("Failed to open the application file: %1, server thread exiting.")).arg(m_appfile));
         return;
     }
 
@@ -81,7 +81,7 @@ void Server::run()
     PyRun_SimpleString(QString("PGADMIN_PORT = %1").arg(m_port).toLatin1());
 
     if (PyRun_SimpleFile(cp, m_appfile.toUtf8().data()) != 0)
-        setError("Failed to launch the application server, server thread exiting.");
+        setError(tr("Failed to launch the application server, server thread exiting."));
 
     fclose(cp);
 }

runtime/pgAdmin4.cpp

@@ -38,7 +38,8 @@ int main(int argc, char * argv[])
     QCoreApplication::setOrganizationDomain("pgadmin.org");
     QCoreApplication::setApplicationName(PGA_APP_NAME);
 
-    // Find an unused port number.
+    // Find an unused port number. Essentially, we're just reserving one
+    // here that CherryPy will use when we start up the server.
     QTcpSocket socket;
     socket.bind(0, QAbstractSocket::DontShareAddress);
     quint16 port = socket.localPort();
@@ -50,19 +51,89 @@ int main(int argc, char * argv[])
     {
         qDebug() << server->getError();
 
-        QString error("An error occurred initialising the application server:\n\n" + server->getError());
-        QMessageBox::critical(NULL, QString("Fatal Error"), error);
+        QString error = QString(QWidget::tr("An error occurred initialising the application server:\n\n%1")).arg(server->getError());
+        QMessageBox::critical(NULL, QString(QWidget::tr("Fatal Error")), error);
 	
         exit(1);
     }
 
     server->start();
 
+    // Generate the app server URL
+    QString appServerUrl = QString("http://localhost:%1").arg(port);
+
+    // Now the server should be up, we'll attempt to connect and get a response.
+    // We'll retry in a loop a few time before aborting if necessary. The browser
+    // will also retry - that shouldn't (in theory) be necessary, but it won't
+    // hurt.
+    int attempt = 0;
+    while (attempt++ < 10)
+    {
+        bool alive = PingServer(QUrl(appServerUrl));
+
+        if (alive)
+        {
+            break;
+        }
+
+        if (attempt == 10)
+        {
+            QString error(QWidget::tr("The application server could not be contacted."));
+            QMessageBox::critical(NULL, QString(QWidget::tr("Fatal Error")), error);
+
+            exit(1);
+        }
+
+        sleep(1);
+    }
+
     // Create & show the main window
-    BrowserWindow browserWindow(port);
+    BrowserWindow browserWindow(appServerUrl);
     browserWindow.show();
 
     // Go!
     return app.exec();
 }
 
+<<<<<<< HEAD
+=======
+bool PingServer(QUrl url)
+{
+    QNetworkAccessManager manager;
+    QEventLoop loop;
+    QNetworkReply *reply;
+    QVariant redirectUrl;
+
+    url.setPath("/ping");
+
+    do
+    {
+        reply = manager.get(QNetworkRequest(url));
+
+        QObject::connect(reply, SIGNAL(finished()), &loop, SLOT(quit()));
+        loop.exec();
+
+        redirectUrl = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
+        url = redirectUrl.toUrl();
+
+        if (!redirectUrl.isNull())
+            delete reply;
+
+    } while (!redirectUrl.isNull());
+
+    if (reply->error() != QNetworkReply::NoError)
+    {
+        return false;
+    }
+
+    QString response = reply->readAll();
+
+    if (response != "PING")
+    {
+        qDebug() << "Failed to connect, server response: " << response;
+        return false;
+    }
+
+    return true;
+}
+>>>>>>> Have the runtime check in a loop to see if the app server is up before

runtime/pgAdmin4.h

@@ -28,4 +28,8 @@
 // Application name
 const QString PGA_APP_NAME = QString("pgAdmin 4");
 
+// Global function prototypes
+int main(int argc, char * argv[]);
+bool PingServer(QUrl url);
+
 #endif // PGADMIN4_H