Error messages.

.travis.yml

@@ -37,4 +37,4 @@ script:
   - CTEST_OUTPUT_ON_FAILURE=1 make test
 
 after_success:
-  - coveralls --root .. --build-root . -e tests/ -E .*googletest.* -E .*CMakeFiles.* -E .+/moc_.* -E .+/mocs_.* -E .+/qrc_.* -E .+/qxt.* -E .+/ui_.* > coveralls.log
+  - coveralls --root .. --build-root . -e tests/ -E .*googletest.* -E .*glog.* -E .*CMakeFiles.* -E .+/moc_.* -E .+/mocs_.* -E .+/qrc_.* -E .+/qxt.* -E .+/ui_.* > coveralls.log

CMakeLists.txt

@@ -20,6 +20,9 @@ else ()
     set(gtest_disable_pthreads ON)
 endif ()
 
+# Set gflags off.
+set(WITH_GFLAGS OFF CACHE BOOL "Use gflags")
+
 # Coverage.
 option(COVERAGE "Generate coverage data" OFF)
 if (COVERAGE)
@@ -32,6 +35,13 @@ if (COVERAGE)
     endif ()
 endif ()
 
+# Add a logging tool.
+include(cmake/glog.cmake)
+fetch_glog(
+        ${PROJECT_SOURCE_DIR}/cmake
+        ${PROJECT_BINARY_DIR}/glog
+)
+
 # Add source folder.
 add_subdirectory(src)
 

README.md

@@ -1,4 +1,7 @@
-# instant-translator [![Build Status](https://travis-ci.org/ugnelis/instant-translator.svg?branch=master)](https://travis-ci.org/ugnelis/instant-translator) [![Coverage Status](https://coveralls.io/repos/github/ugnelis/instant-translator/badge.svg?branch=master)](https://coveralls.io/github/ugnelis/instant-translator?branch=master)
+# instant-translator
+[![Build Status](https://travis-ci.org/ugnelis/instant-translator.svg?branch=master)](https://travis-ci.org/ugnelis/instant-translator)
+[![Coverage Status](https://coveralls.io/repos/github/ugnelis/instant-translator/badge.svg?branch=master)](https://coveralls.io/github/ugnelis/instant-translator?branch=master)
+
 Translate words and sentences instantly. Program uses APIs of various translators.
 
 ## What Does the App Solve?
@@ -27,6 +30,12 @@ key=AsjSAXXX
 format=text
 ```
 
+### Turn On Logs
+In this project gflags library isn't used. That is why environment variable `GLOG_logtostderr` has to be set in order to see logs.
+```bash
+GLOG_logtostderr=1 ./instant_translator
+```
+
 ### Translate by Pressing the Keyboard
 Currently, it's made that when clipboard (copy or cut operation) is changed then the app translates the text.
 

cmake/glog-download.cmake

@@ -0,0 +1,17 @@
+cmake_minimum_required(VERSION 3.5 FATAL_ERROR)
+
+project(glog-download NONE)
+
+include(ExternalProject)
+
+ExternalProject_Add(glog
+        SOURCE_DIR "@GLOG_DOWNLOAD_ROOT@/glog-src"
+        BINARY_DIR "@GLOG_DOWNLOAD_ROOT@/glog-build"
+        GIT_REPOSITORY
+        https://github.com/google/glog.git
+        GIT_TAG
+        v0.3.5
+        CONFIGURE_COMMAND ""
+        BUILD_COMMAND ""
+        INSTALL_COMMAND ""
+        TEST_COMMAND "")

cmake/glog.cmake

@@ -0,0 +1,25 @@
+macro(fetch_glog _download_module_path _download_root)
+    set(GLOG_DOWNLOAD_ROOT ${_download_root})
+    configure_file(
+            ${_download_module_path}/glog-download.cmake
+            ${_download_root}/CMakeLists.txt
+            @ONLY)
+
+    unset(GLOG_DOWNLOAD_ROOT)
+
+    execute_process(
+            COMMAND
+            "${CMAKE_COMMAND}" -G "${CMAKE_GENERATOR}" .
+            WORKING_DIRECTORY
+            ${_download_root})
+
+    execute_process(
+            COMMAND
+            "${CMAKE_COMMAND}" --build .
+            WORKING_DIRECTORY
+            ${_download_root})
+
+    add_subdirectory(
+            ${_download_root}/glog-src
+            ${_download_root}/glog-build)
+endmacro()

src/CMakeLists.txt

@@ -26,6 +26,9 @@ set(QT5_LIBRARIES
         Qt5::Network
         Qt5::Concurrent)
 
+set(OTHER_LIBRARIES
+        glog)
+
 # UI files.
 qt5_wrap_ui(UI_HEADERS mainwindow.ui)
 
@@ -52,4 +55,4 @@ set(SOURCE_FILES
 add_executable(instant_translator ${SOURCE_FILES} ${RESOURCE_FILES_ADDED} ${UI_HEADERS})
 
 # Use the Widgets module from Qt5.
-target_link_libraries(instant_translator ${QT5_LIBRARIES})
+target_link_libraries(instant_translator ${QT5_LIBRARIES} ${OTHER_LIBRARIES})

src/apis/googleapi.cpp

@@ -38,7 +38,7 @@ QString GoogleAPI::translate(const QString &input,
 
     QNetworkAccessManager *manager = new QNetworkAccessManager();
 
-    RequestManager requestManager(nullptr, std::move(manager));
+    RequestManager requestManager(nullptr, manager);
     requestManager.postRequest(request, postJsonDocument.toJson());
 
     // Parse the replay.
@@ -47,6 +47,17 @@ QString GoogleAPI::translate(const QString &input,
     QJsonDocument replyJsonDocument = QJsonDocument::fromJson(replyByteArray.data());
     QJsonObject replyJsonObject = replyJsonDocument.object();
 
+    // If error.
+    if (replyJsonObject.contains("error")) {
+        QJsonObject errorJsonObject = replyJsonObject["error"].toObject();
+        int errorCode = errorJsonObject["code"].toInt();
+        std::string errorMessage = errorJsonObject["message"]
+                .toString()
+                .toStdString();
+        std::string exceptionMessage = "Error " + std::to_string(errorCode) + ": " + errorMessage;
+        throw std::invalid_argument(exceptionMessage);
+    }
+
     QJsonArray translationsJsonArray = replyJsonObject["data"]
             .toObject()["translations"]
             .toArray();
@@ -74,7 +85,7 @@ QStringList GoogleAPI::getSupportedLanguages() const {
 
     QNetworkAccessManager *manager = new QNetworkAccessManager();
 
-    RequestManager requestManager(nullptr, std::move(manager));
+    RequestManager requestManager(nullptr, manager);
     requestManager.getRequest(request);
 
     // Parse the replay.
@@ -83,6 +94,17 @@ QStringList GoogleAPI::getSupportedLanguages() const {
     QJsonDocument replyJsonDocument = QJsonDocument::fromJson(replyByteArray.data());
     QJsonObject replyJsonObject = replyJsonDocument.object();
 
+    // If error.
+    if (replyJsonObject.contains("error")) {
+        QJsonObject errorJsonObject = replyJsonObject["error"].toObject();
+        int errorCode = errorJsonObject["code"].toInt();
+        std::string errorMessage = errorJsonObject["message"]
+                .toString()
+                .toStdString();
+        std::string exceptionMessage = "Error " + std::to_string(errorCode) + ": " + errorMessage;
+        throw std::invalid_argument(exceptionMessage);
+    }
+
     QJsonArray languagesJsonArray = replyJsonObject["data"]
             .toObject()["languages"]
             .toArray();

src/apis/googleapi.h

@@ -1,6 +1,7 @@
 #ifndef INSTANT_TRANSLATOR_GOOGLEAPI_H
 #define INSTANT_TRANSLATOR_GOOGLEAPI_H
 
+#include <stdexcept>
 #include <QObject>
 #include <QSettings>
 #include <QJsonDocument>

src/main.cpp

@@ -1,8 +1,12 @@
 #include <QApplication>
 #include <QSettings>
+#include <glog/logging.h>
 #include "mainwindow.h"
 
 int main(int argc, char *argv[]) {
+    // Logging tool.
+    google::InitGoogleLogging(argv[0]);
+
     QApplication application(argc, argv);
 
     // Settings.

src/mainwindow.cpp

@@ -125,22 +125,44 @@ QString MainWindow::runTranslation(API *api,
                                    const QString &sourceLanguage,
                                    const QString &targetLanguage) {
     if (api == nullptr) {
+        showErrorBox("Text cannot be translated. API is not set.");
         return QString();
     }
 
-    QString outputString = api->translate(inputString, sourceLanguage, targetLanguage);
+    QString outputString;
+    try {
+        outputString = api->translate(inputString, sourceLanguage, targetLanguage);
+    } catch (const std::invalid_argument &e) {
+        showErrorBox(e.what());
+    }
+
     return outputString;
 }
 
 QStringList MainWindow::runGetSupportedLanguages(API *api) {
     if (api == nullptr) {
+        showErrorBox("Languages list cannot be received. API is not set.");
         return QStringList();
     }
 
-    QStringList supportedLanguages = api->getSupportedLanguages();
+    QStringList supportedLanguages;
+    try {
+        supportedLanguages = api->getSupportedLanguages();
+    } catch (const std::invalid_argument &e) {
+        showErrorBox(e.what());
+    }
+
     return supportedLanguages;
 }
 
+void MainWindow::showErrorBox(const QString &message) {
+    DLOG(INFO) << message.toStdString();
+    QMessageBox messageBox;
+    messageBox.setText(message);
+    messageBox.setIcon(QMessageBox::Warning);
+    messageBox.exec();
+}
+
 void MainWindow::on_exitAction_triggered() {
     this->close();
 }

src/mainwindow.h

@@ -1,12 +1,15 @@
 #ifndef MAINWINDOW_H
 #define MAINWINDOW_H
 
+#include <stdexcept>
 #include <QMainWindow>
 #include <QClipboard>
 #include <QFuture>
 #include <QFutureWatcher>
 #include <QtConcurrent>
 #include <QStringList>
+#include <QMessageBox>
+#include <glog/logging.h>
 #include "apis/api.h"
 #include "apis/googleapi.h"
 #include "utils/language.h"
@@ -92,6 +95,12 @@ private slots:
      */
     QStringList runGetSupportedLanguages(API *api);
 
+    /**
+     * Show error box.
+     * @param message Error message.
+     */
+    void showErrorBox(const QString &message);
+
     Ui::MainWindow *ui;     // MainWindow user interface.
     QClipboard *clipboard;  // Clipboard information.
     API *api;               // Translation API.