refactor: proxy commandline arguments

Add a 'proxy' to forward external API calls into the main application
control flow. Right now it only supports forwarding commandline
arguments, but this construct is already useful as a starting point for
future D-Bus API support.

autotests/app/CMakeLists.txt

@@ -1,9 +1,9 @@
 #
 # SPDX-License-Identifier: BSD-2-Clause
-# SPDX-FileCopyrightText: 2020 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
+# SPDX-FileCopyrightText: 2020-2021 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
 #
 
-set(Test_DEP_LIBS Qt5::Core Qt5::Concurrent Qt5::Test keysmith_lib test_lib)
+set(Test_DEP_LIBS Qt5::Core Qt5::Gui Qt5::Concurrent Qt5::Test keysmith_lib test_lib)
 
 set(app_test_SRCS
     commandline-account-job.cpp

src/app/cli.cpp

@@ -1,10 +1,12 @@
 /*
  * SPDX-License-Identifier: GPL-3.0-or-later
- * SPDX-FileCopyrightText: 2020 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
+ * SPDX-FileCopyrightText: 2020-2021 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
  */
 #include "cli.h"
 #include "../logging_p.h"
 #include "../model/qr.h"
+#include "flows_p.h"
+#include "state_p.h"
 
 #include <KLocalizedString>
 #include <QCommandLineOption>
@@ -16,10 +18,7 @@ namespace app
 {
     void CommandLineOptions::addOptions(QCommandLineParser &parser)
     {
-        parser.addPositionalArgument(
-            QStringLiteral("<uri>"),
-            i18nc("@info (<uri> placeholder)", "Optional account to add, formatted as otpauth:// URI (e.g. from a QR code)")
-        );
+        Proxy::addOptions(parser);
     }
 
     CommandLineOptions::CommandLineOptions(QCommandLineParser &parser, bool parseOk, QObject *parent) :
@@ -107,4 +106,67 @@ namespace app
             qCDebug(logger) << "Failed to signal result of processing the URI passed on the commandline";
         }
     }
+
+    Proxy::Proxy(QGuiApplication *app, QObject *parent) :
+        QObject(parent), m_keysmith(nullptr), m_app(app)
+    {
+        Q_ASSERT_X(m_app, Q_FUNC_INFO, "Should have a valid QGuiApplication instance");
+    }
+
+    void Proxy::addOptions(QCommandLineParser &parser)
+    {
+        parser.addPositionalArgument(
+            QStringLiteral("<uri>"),
+            i18nc("@info (<uri> placeholder)", "Optional account to add, formatted as otpauth:// URI (e.g. from a QR code)")
+        );
+    }
+
+    bool Proxy::parseCommandLine(QCommandLineParser &parser, const QStringList &argv)
+    {
+        // options that will be handled via UI interaction
+        app::Proxy::addOptions(parser);
+        return parser.parse(argv);
+    }
+
+    void Proxy::disable(void)
+    {
+        m_keysmith = nullptr;
+    }
+
+    bool Proxy::enable(Keysmith *keysmith)
+    {
+        Q_ASSERT_X(keysmith, Q_FUNC_INFO, "should be given a valid Keysmith instance");
+        if (m_keysmith) {
+            qCDebug(logger)
+                << "Not (re)initialising proxy with new Keysmith instance:" << keysmith
+                << "Already initialised with:" << m_keysmith;
+            return false;
+        }
+
+        m_keysmith = keysmith;
+        QObject::connect(m_keysmith, &QObject::destroyed, this, &Proxy::disable);
+        return true;
+    }
+
+    bool Proxy::proxy(const QCommandLineParser &parser, bool parsedOk)
+    {
+        if (!parsedOk) {
+            qCDebug(logger) << "Not proxying to Keysmith instance: invalid command line";
+            return false;
+        }
+        if (!m_keysmith) {
+            qCDebug(logger) << "Not proxying command line arguments: not initialised with a Keysmith instance";
+            return false;
+        }
+
+        auto state = flowStateOf(m_keysmith);
+        if (state->flowRunning()) {
+            qCDebug(logger) << "Not proxying command line arguments: a 'competing' flow is already running";
+            return false;
+        }
+
+        (new InitialFlow(m_keysmith))->run(parser);
+        return true;
+    }
+
 }

src/app/cli.h

@@ -1,15 +1,18 @@
 /*
  * SPDX-License-Identifier: GPL-3.0-or-later
- * SPDX-FileCopyrightText: 2020 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
+ * SPDX-FileCopyrightText: 2020-2021 Johan Ouwerkerk <jm.ouwerkerk@gmail.com>
  */
 #ifndef APP_COMMAND_LINE_H
 #define APP_COMMAND_LINE_H
 
+#include "keysmith.h"
 #include "../model/input.h"
 
 #include <QCommandLineParser>
+#include <QGuiApplication>
 #include <QObject>
 #include <QString>
+#include <QStringList>
 
 namespace app
 {
@@ -56,6 +59,23 @@ namespace app
         const QString m_errorText;
         QCommandLineParser &m_parser;
     };
+
+    class Proxy: public QObject
+    {
+        Q_OBJECT
+    public:
+        static bool parseCommandLine(QCommandLineParser &parser, const QStringList &argv);
+        static void addOptions(QCommandLineParser &parser);
+    public:
+        explicit Proxy(QGuiApplication *app, QObject *parent = nullptr);
+        bool enable(Keysmith *keysmith);
+        bool proxy(const QCommandLineParser &parser, bool parsedOk);
+    private Q_SLOTS:
+        void disable(void);
+    private:
+        Keysmith * m_keysmith;
+        QGuiApplication *m_app;
+    };
 };
 
 #endif

src/main.cpp

@@ -46,14 +46,12 @@ Q_DECL_EXPORT int main(int argc, char *argv[])
     QGuiApplication::setApplicationDisplayName(i18nc("@title", "Keysmith"));
 
     QCommandLineParser cliParser;
-    // options that will be handled via UI interaction
-    app::CommandLineOptions::addOptions(cliParser);
 
     // default/boilerplate options handled entirely via command line
     const auto helpOption = cliParser.addHelpOption();
     const auto versionOption = cliParser.addVersionOption();
 
-    bool parseOk = cliParser.parse(QCoreApplication::arguments());
+    bool parseOk = app::Proxy::parseCommandLine(cliParser, QCoreApplication::arguments());
 
     /*
      * First check for pure command line options and handle these.
@@ -71,6 +69,8 @@ Q_DECL_EXPORT int main(int argc, char *argv[])
         return 0; // just to be explicit: showVersion() is documented to call exit()
     }
 
+    app::Proxy proxy(&app);
+
     QQmlApplicationEngine engine;
     engine.rootContext()->setContextObject(new KLocalizedContext(&engine));
 
@@ -90,11 +90,13 @@ Q_DECL_EXPORT int main(int argc, char *argv[])
     qmlRegisterType<validators::IssuerValidator>("Keysmith.Validators", 1, 0, "AccountIssuerValidator");
     qmlRegisterType<validators::Base32Validator>("Keysmith.Validators", 1, 0, "Base32SecretValidator");
     qmlRegisterType<validators::UnsignedLongValidator>("Keysmith.Validators", 1, 0, "HOTPCounterValidator");
-    qmlRegisterSingletonType<app::Keysmith>("Keysmith.Application", 1, 0, "Keysmith", [](QQmlEngine *qml, QJSEngine *js) -> QObject *
+    qmlRegisterSingletonType<app::Keysmith>("Keysmith.Application", 1, 0, "Keysmith", [&proxy](QQmlEngine *qml, QJSEngine *js) -> QObject *
     {
         Q_UNUSED(js);
 
-        return new app::Keysmith(new app::Navigation(qml));
+        auto app = new app::Keysmith(new app::Navigation(qml));
+        proxy.enable(app);
+        return app;
     });
     qmlRegisterSingletonType<app::CommandLineOptions>("Keysmith.Application", 1, 0, "CommandLine", [parseOk, &cliParser](QQmlEngine *qml, QJSEngine *js) -> QObject *
     {