Try to fix #119

src/connection.cpp

@@ -71,7 +71,21 @@ void ConnectionLoader::loadConnection()
 
 void ConnectionLoader::loadProgress()
 {
-    QTimer::singleShot(1, [=]() { this->ShowProgress(); });
+    bool failed = false;
+    QTimer::singleShot(1, [=]() mutable {
+        // continually retry ShowProgress() until it succeeds
+        // by running without an exception
+        do {
+            try {
+                this->ShowProgress();
+                failed = false;
+            } catch (const std::exception& e)  {
+                DEBUG("caught exception " << e.what() );
+                failed = true;
+            }
+        } while (failed);
+
+    });
     if (!Settings::getInstance()->isHeadless())
         d->exec();
 }
@@ -85,7 +99,7 @@ void ConnectionLoader::ShowProgress()
 
     auto connection = makeConnection(config);
     auto me   = this;
-    qDebug() << __func__ << ": server=" <<  config->server << " connection=" << connection << " me=" << me;
+    DEBUG("server=" <<  config->server << " connection=" << connection << " me=" << me);
 
     isSyncing = new QAtomicInteger<bool>();
     isSyncing->store(true);
@@ -101,39 +115,42 @@ void ConnectionLoader::ShowProgress()
         // When sync is done, set the connection
         this->doRPCSetConnectionShield(connection);
     });
-    
+
     // While it is syncing, we'll show the status updates while it is alive.
     QObject::connect(syncTimer, &QTimer::timeout, [=]() {
         // Check the sync status
         if (isSyncing != nullptr && isSyncing->load()) {
             // Get the sync status
-    
             try {
-            connection->doRPC("syncstatus", "", [=](json reply) {
-                if (isSyncing != nullptr && reply.find("synced_blocks") != reply.end())
-    
-                {
-                    qint64 synced = reply["synced_blocks"].get<json::number_unsigned_t>();
-                    qint64 total = reply["total_blocks"].get<json::number_unsigned_t>();
-                    me->showInformation(
-                        "Syncing... " + QString::number(synced) + " / " + QString::number(total)
-                    );
-                }
-            },
-            [=](QString err) {
-                qDebug() << "Sync error" << err;
-            });
-        }catch (...)
-        {
-            main->logger->write("catch sync progress reply");
-        }
-    
+                connection->doRPC("syncstatus", "", [=](json reply) {
+                    if (isSyncing != nullptr && reply.find("synced_blocks") != reply.end()) {
+                        qint64 synced = reply["synced_blocks"].get<json::number_unsigned_t>();
+                        qint64 total = reply["total_blocks"].get<json::number_unsigned_t>();
+                        me->showInformation(
+                            "Syncing... " + QString::number(synced) + " / " + QString::number(total)
+                        );
+                    }
+                }, [=](QString err) {
+                    DEBUG("Sync error " << err);
+                    // We may have gotten "Unexpected compression flag: 60"
+                    // or some other error, so let's try another server
+                    config->server = Settings::getRandomServer();
+                    DEBUG("Changed server to " << config->server );
+                });
+            } catch (const std::exception& e)  {
+                DEBUG("syncstatus exception: " << e.what() );
+                main->logger->write("catch sync progress reply");
+
+                // rethrow exception so loadProgress can catch
+                // it and retry the entire ShowProgress() function again
+                throw new std::runtime_error(std::string("syncstatus failed"));
+            }
         }
-});
+    });
 
-syncTimer->setInterval(1* 1000);
-syncTimer->start();
-main->logger->write("Start sync timer");
+    syncTimer->setInterval(1*1000);
+    syncTimer->start();
+    main->logger->write("Start sync timer");
 
 }
 

src/mainwindow.cpp

@@ -1095,10 +1095,10 @@ void MainWindow::payhushURI(QString uri, QString myAddr) {
             // Save the wallet
             this->getRPC()->saveWallet([=] (auto) {
                 // Then reload the connection. The ConnectionLoader deletes itself.
-               auto cl = new ConnectionLoader(this, rpc);
+                auto cl = new ConnectionLoader(this, rpc);
                 cl->loadProgress();
-                         });       
-                     });    
+            });
+          });
 
     }else if ((pui.rescan->isChecked() == true) && (pui.privKeyTxt->toPlainText().startsWith("secret"))){