add fingerprint snap decisions; test with notification dbusmock

9 files changed, 611 insertions, 38 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9fa4d10..8b8ef65 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
-project (indicator-display)
-cmake_minimum_required (VERSION 2.8.9)
+project(indicator-display LANGUAGES C CXX)
+cmake_minimum_required(VERSION 2.8.9)
 
 list (APPEND CMAKE_MODULE_PATH ${CMAKE_SOURCE_DIR}/cmake)
 
@@ -15,9 +15,6 @@ set (SERVICE_EXEC "${PACKAGE}-service")
 option (enable_tests "Build the package's automatic tests." ON)
 option (enable_lcov "Generate lcov code coverage reports." ON)
 
-set(THREADS_PREFER_PTHREAD_FLAG ON)
-find_package(Threads REQUIRED)
-
 ##
 ##  GNU standard paths
 ## 
@@ -33,9 +30,10 @@ set (CMAKE_INSTALL_FULL_PKGLIBEXECDIR "${CMAKE_INSTALL_FULL_LIBEXECDIR}/${CMAKE_
 ##  Check for prerequisites
 ##
 
+set(THREADS_PREFER_PTHREAD_FLAG ON)
+find_package(Threads REQUIRED)
 find_package (PkgConfig REQUIRED)
 
-include (FindPkgConfig)
 pkg_check_modules (SERVICE_DEPS REQUIRED
                    gio-unix-2.0>=2.36
                    glib-2.0>=2.36)
@@ -58,9 +56,6 @@ set (CXX_WARNING_ARGS "${CXX_WARNING_ARGS} -Wno-missing-field-initializers") # G
 
 # testing & coverage
 if (${enable_tests})
-  set (GTEST_SOURCE_DIR /usr/src/gtest/src)
-  set (GTEST_INCLUDE_DIR ${GTEST_SOURCE_DIR}/..)
-  set (GTEST_LIBS -lpthread)
   enable_testing ()
   if (${enable_lcov})
     include(GCov)
diff --git a/cmake/FindGMock.cmake b/cmake/FindGMock.cmake
deleted file mode 100644
index 74a1c15..0000000
--- a/cmake/FindGMock.cmake
+++ /dev/null
@@ -1,10 +0,0 @@
-# Build with system gmock and embedded gtest
-set (GMOCK_INCLUDE_DIRS "/usr/include/gmock/include" CACHE PATH "gmock source include directory")
-set (GMOCK_SOURCE_DIR "/usr/src/gmock" CACHE PATH "gmock source directory")
-set (GTEST_INCLUDE_DIRS "${GMOCK_SOURCE_DIR}/gtest/include" CACHE PATH "gtest source include directory")
-
-add_subdirectory(${GMOCK_SOURCE_DIR} "${CMAKE_CURRENT_BINARY_DIR}/gmock")
-
-set(GTEST_LIBRARIES gtest)
-set(GTEST_MAIN_LIBRARIES gtest_main)
-set(GMOCK_LIBRARIES gmock gmock_main)
diff --git a/debian/control b/debian/control
index 4f05f74..5088af5 100644
--- a/debian/control
+++ b/debian/control
@@ -3,12 +3,17 @@ Section: misc
 Priority: optional
 Maintainer: Charles Kerr <charles.kerr@canonical.com>
 Build-Depends: cmake,
+               cmake-extras (>= 0.4),
                dbus,
                libglib2.0-dev (>= 2.36),
                libproperties-cpp-dev,
 # for coverage reports
                lcov,
 # for tests
+               qt5-default,
+               qtbase5-dev,
+               libqtdbusmock1-dev (>= 0.4),
+               libqtdbustest1-dev,
                cppcheck,
                libgtest-dev,
                google-mock (>= 1.6.0+svn437),
diff --git a/src/main.cpp b/src/main.cpp
index 0c56bd6..62eca62 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -20,6 +20,7 @@
 #include <src/adbd-client.h>
 #include <src/exporter.h>
 #include <src/rotation-lock.h>
+#include <src/usb-snap.h>
 
 #include <glib/gi18n.h> // bindtextdomain()
 #include <gio/gio.h>
@@ -60,9 +61,11 @@ main(int /*argc*/, char** /*argv*/)
     static constexpr char const * ADB_SOCKET_PATH {"/dev/socket/adb"};
     GAdbdClient adbd_client{ADB_SOCKET_PATH};
     adbd_client.on_pk_request().connect([](const AdbdClient::PKRequest& req){
-        g_debug("%s got pk_request [%s]", G_STRLOC, req.public_key.c_str());
-        // FIXME: actually decide what response to send back
-        req.respond(AdbdClient::PKResponse::ALLOW);
+        auto snap = new UsbSnap(req.public_key);
+        snap->on_user_response().connect([req,snap](AdbdClient::PKResponse response, bool /*FIXME: remember_choice*/){
+            req.respond(response);
+            g_idle_add([](gpointer gsnap){delete static_cast<UsbSnap*>(gsnap); return G_SOURCE_REMOVE;}, snap); // delete-later
+        });
     });
 
     g_main_loop_run(loop);
diff --git a/src/usb-snap.cpp b/src/usb-snap.cpp
new file mode 100644
index 0000000..40f02a2
--- /dev/null
+++ b/src/usb-snap.cpp
@@ -0,0 +1,254 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Charles Kerr <charles.kerr@canonical.com>
+ */
+
+#include <src/usb-snap.h>
+
+#include <glib/gi18n.h>
+#include <gio/gio.h>
+
+/***
+****
+***/
+
+class UsbSnap::Impl
+{
+public:
+
+    explicit Impl(const std::string& fingerprint):
+        m_fingerprint{fingerprint},
+        m_cancellable{g_cancellable_new()}
+    {
+        g_bus_get (G_BUS_TYPE_SESSION, m_cancellable, on_bus_ready_static, this);
+    }
+
+    ~Impl()
+    {
+        g_cancellable_cancel(m_cancellable);
+        g_clear_object(&m_cancellable);
+
+        if (m_subscription_id != 0)
+            g_dbus_connection_signal_unsubscribe (m_bus, m_subscription_id);
+
+        if (m_notification_id != 0) {
+            GError* error {};
+            g_dbus_connection_call_sync(m_bus,
+                                        BUS_NAME,
+                                        OBJECT_PATH,
+                                        IFACE_NAME,
+                                        "CloseNotification",
+                                        g_variant_new("(u)", m_notification_id),
+                                        nullptr,
+                                        G_DBUS_CALL_FLAGS_NONE,
+                                        -1,
+                                        nullptr,
+                                        &error);
+            if (error != nullptr) {
+                g_warning("Error closing notification: %s", error->message);
+                g_clear_error(&error);
+            }
+        }
+
+        g_clear_object(&m_bus);
+    }
+
+    core::Signal<AdbdClient::PKResponse,bool>& on_user_response()
+    {
+        return m_on_user_response;
+    }
+
+private:
+
+    static void on_bus_ready_static(GObject* /*source*/, GAsyncResult* res, gpointer gself)
+    {
+        GError* error {};
+        auto bus = g_bus_get_finish (res, &error);
+        if (error != nullptr) {
+            if (!g_error_matches(error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+                g_warning("UsbSnap: Error getting session bus: %s", error->message);
+            g_clear_error(&error);
+        } else {
+            static_cast<Impl*>(gself)->on_bus_ready(bus);
+        }
+        g_clear_object(&bus);
+    }
+
+    void on_bus_ready(GDBusConnection* bus)
+    {
+        m_bus = G_DBUS_CONNECTION(g_object_ref(G_OBJECT(bus)));
+
+        auto body = g_strdup_printf(_("The computer's RSA key fingerprint is: %s"), m_fingerprint.c_str());
+
+        GVariantBuilder actions_builder;
+        g_variant_builder_init(&actions_builder, G_VARIANT_TYPE_STRING_ARRAY);
+        g_variant_builder_add(&actions_builder, "s", ACTION_ALLOW);
+        g_variant_builder_add(&actions_builder, "s", _("Allow"));
+        g_variant_builder_add(&actions_builder, "s", ACTION_DENY);
+        g_variant_builder_add(&actions_builder, "s", _("Deny"));
+
+        GVariantBuilder hints_builder;
+        g_variant_builder_init(&hints_builder, G_VARIANT_TYPE_VARDICT);
+        g_variant_builder_add(&hints_builder, "{sv}", "x-canonical-non-shaped-icon", g_variant_new_string("true"));
+        g_variant_builder_add(&hints_builder, "{sv}", "x-canonical-snap-decisions", g_variant_new_string("true"));
+        g_variant_builder_add(&hints_builder, "{sv}", "x-canonical-private-affirmative-tint", g_variant_new_string("true"));
+
+        auto args = g_variant_new("(susssasa{sv}i)",
+                                  "",
+                                  uint32_t(0),
+                                  "computer-symbolic",
+                                  _("Allow USB Debugging?"),
+                                  body,
+                                  &actions_builder,
+                                  &hints_builder,
+                                  -1);
+        g_dbus_connection_call(m_bus,
+                               BUS_NAME,
+                               OBJECT_PATH,
+                               IFACE_NAME,
+                               "Notify",
+                               args,
+                               G_VARIANT_TYPE("(u)"),
+                               G_DBUS_CALL_FLAGS_NONE,
+                               -1, // timeout
+                               m_cancellable,
+                               on_notify_reply_static,
+                               this);
+
+        g_clear_pointer(&body, g_free);
+    }
+
+    static void on_notify_reply_static(GObject* obus, GAsyncResult* res, gpointer gself)
+    {
+        GError* error {};
+        auto reply = g_dbus_connection_call_finish (G_DBUS_CONNECTION(obus), res, &error);
+        if (error != nullptr) {
+            if (!g_error_matches(error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
+                g_warning("UsbSnap: Error calling Notify: %s", error->message);
+            g_clear_error(&error);
+        } else {
+            uint32_t id {};
+            g_variant_get(reply, "(u)", &id);
+            static_cast<Impl*>(gself)->on_notify_reply(id);
+        }
+        g_clear_pointer(&reply, g_variant_unref);
+    }
+
+    void on_notify_reply(uint32_t id)
+    {
+        m_notification_id = id;
+
+        m_subscription_id = g_dbus_connection_signal_subscribe(m_bus,
+                                                               BUS_NAME,
+                                                               IFACE_NAME,
+                                                               nullptr,
+                                                               OBJECT_PATH,
+                                                               nullptr,
+                                                               G_DBUS_SIGNAL_FLAGS_NONE,
+                                                               on_notification_signal_static,
+                                                               this,
+                                                               nullptr);
+    }
+
+    static void on_notification_signal_static(GDBusConnection* /*connection*/,
+                                              const gchar* /*sender_name*/,
+                                              const gchar* object_path,
+                                              const gchar* interface_name,
+                                              const gchar* signal_name,
+                                              GVariant* parameters,
+                                              gpointer gself)
+    {
+        g_return_if_fail(!g_strcmp0(object_path, OBJECT_PATH));
+        g_return_if_fail(!g_strcmp0(interface_name, IFACE_NAME));
+
+        auto self = static_cast<Impl*>(gself);
+
+        if (!g_strcmp0(signal_name, "ActionInvoked"))
+        {
+            uint32_t id {};
+            const char* action_name {};
+            g_variant_get(parameters, "(u&s)", &id, &action_name);
+            if (id == self->m_notification_id)
+                self->on_action_invoked(action_name);
+        }
+        else if (!g_strcmp0(signal_name, "NotificationClosed"))
+        {
+            uint32_t id {};
+            uint32_t close_reason {};
+            g_variant_get(parameters, "(uu)", &id, &close_reason);
+            if (id == self->m_notification_id)
+                self->on_notification_closed(close_reason);
+        }
+    }
+
+    void on_action_invoked(const char* action_name)
+    {
+        const auto response = !g_strcmp0(action_name, ACTION_ALLOW)
+            ? AdbdClient::PKResponse::ALLOW
+            : AdbdClient::PKResponse::DENY;
+
+        // FIXME: the current default is to cover the most common use case.
+        // We need to get the notification ui's checkbox working ASAP so
+        // that the user can provide this flag
+        const bool remember_this_choice = response == AdbdClient::PKResponse::ALLOW;
+
+        m_on_user_response(response, remember_this_choice);
+    }
+
+    void on_notification_closed(uint32_t close_reason)
+    {
+        if (close_reason == CloseReason::EXPIRED)
+            m_on_user_response(AdbdClient::PKResponse::DENY, false);
+
+        m_notification_id = 0;
+    }
+
+    static constexpr char const * ACTION_ALLOW{"allow"};
+    static constexpr char const * ACTION_DENY{"deny"};
+
+    static constexpr char const * BUS_NAME    {"org.freedesktop.Notifications" };
+    static constexpr char const * IFACE_NAME  {"org.freedesktop.Notifications" };
+    static constexpr char const * OBJECT_PATH {"/org/freedesktop/Notifications" };
+    enum CloseReason { EXPIRED=1, DISMISSED=2, API=3, UNDEFINED=4 };
+
+    const std::string m_fingerprint;
+    core::Signal<AdbdClient::PKResponse,bool> m_on_user_response;
+    GCancellable* m_cancellable {};
+    GDBusConnection* m_bus {};
+    uint32_t m_notification_id {};
+    unsigned int m_subscription_id {};
+};
+
+/***
+****
+***/
+
+UsbSnap::UsbSnap(const std::string& public_key):
+    impl{new Impl{public_key}}
+{
+}
+
+UsbSnap::~UsbSnap()
+{
+}
+
+core::Signal<AdbdClient::PKResponse,bool>&
+UsbSnap::on_user_response()
+{
+    return impl->on_user_response();
+}
+
diff --git a/src/usb-snap.h b/src/usb-snap.h
new file mode 100644
index 0000000..6ad3a4c
--- /dev/null
+++ b/src/usb-snap.h
@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Charles Kerr <charles.kerr@canonical.com>
+ */
+
+#pragma once
+
+#include <src/adbd-client.h> // AdbdClient::PKResponse
+
+#include <core/signal.h>
+
+#include <memory>
+#include <string>
+
+class UsbSnap
+{
+public:
+    explicit UsbSnap(const std::string& public_key);
+    ~UsbSnap();
+    core::Signal<AdbdClient::PKResponse,bool>& on_user_response();
+
+protected:
+    class Impl;
+    std::unique_ptr<Impl> impl;
+};
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 706e35b..1fbe407 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,33 +1,57 @@
-include(FindGMock)
-include_directories(${CMAKE_CURRENT_SOURCE_DIR})
-include_directories(${GMOCK_INCLUDE_DIRS})
-include_directories(${GTEST_INCLUDE_DIRS})
+
+set(CMAKE_AUTOMOC ON)
+
+find_package(GMock REQUIRED)
+find_package(Qt5Core REQUIRED)
+find_package(Qt5Test REQUIRED)
+find_package(Qt5DBus COMPONENTS Qt5DBusMacros REQUIRED)
+
+pkg_check_modules(TEST_DEPS
+  libqtdbustest-1 REQUIRED
+  libqtdbusmock-1 REQUIRED
+)
+
+include_directories(
+  ${CMAKE_SOURCE_DIR}
+  ${CMAKE_CURRENT_BINARY_DIR}
+  ${CMAKE_CURRENT_SOURCE_DIR}
+)
+include_directories(SYSTEM
+  ${DBUSTEST_INCLUDE_DIRS}
+  ${TEST_DEPS_INCLUDE_DIRS}
+  ${GTEST_INCLUDE_DIRS}
+  ${GMOCK_INCLUDE_DIRS}
+)
 
 set(CTEST_ENVIRONMENT "${CTEST_ENVIRONMENT};G_MESSAGES_DEBUG=all")
 
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
   # turn off the warnings that break Google Test
-  set (CXX_WARNING_ARGS "${CXX_WARNING_ARGS} -Wno-global-constructors -Wno-weak-vtables -Wno-undef -Wno-c++98-compat-pedantic -Wno-missing-noreturn -Wno-used-but-marked-unused -Wno-padded -Wno-deprecated -Wno-sign-compare -Wno-shift-sign-overflow")
+  set (CXX_WARNING_ARGS "${CXX_WARNING_ARGS} -Wno-global-constructors -Wno-weak-vtables")
 endif()
 
-SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -g -pthread ${CXX_WARNING_ARGS}")
-
-# look for headers in our src dir, and also in the directories where we autogenerate files...
-include_directories (${CMAKE_SOURCE_DIR}/src)
-include_directories (${CMAKE_CURRENT_BINARY_DIR})
-include_directories (${DBUSTEST_INCLUDE_DIRS})
+SET (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC -std=c++11 -g ${CXX_WARNING_ARGS}")
 
 function(add_test_by_name name)
   set (TEST_NAME ${name})
   add_executable (${TEST_NAME} ${TEST_NAME}.cpp)
   add_test (${TEST_NAME} ${TEST_NAME})
- set_property(TEST ${TEST_NAME} PROPERTY ENVIRONMENT "${CTEST_ENVIRONMENT}")
-
-  add_dependencies (${TEST_NAME} libindicatordisplayservice)
-  target_link_libraries (${TEST_NAME} indicatordisplayservice ${SERVICE_DEPS_LIBRARIES} ${GTEST_LIBRARIES} ${GMOCK_LIBRARIES})
+  set_property(TEST ${TEST_NAME} PROPERTY ENVIRONMENT "${CTEST_ENVIRONMENT}")
+  add_dependencies (${TEST_NAME} indicatordisplayservice)
+  target_link_libraries (${TEST_NAME} indicatordisplayservice ${SERVICE_DEPS_LIBRARIES} ${TEST_DEPS_LIBRARIES} ${GTEST_LIBRARIES} ${GMOCK_LIBRARIES})
 endfunction()
 add_test_by_name(rotation-lock-test)
 add_test_by_name(adbd-client-test)
 
-add_test (cppcheck cppcheck --enable=all -USCHEMA_DIR --error-exitcode=2 --inline-suppr -I${CMAKE_SOURCE_DIR} ${CMAKE_SOURCE_DIR}/src ${CMAKE_SOURCE_DIR}/tests)
+function(add_qt_test_by_name name)
+  set (TEST_NAME ${name})
+  add_executable (${TEST_NAME} ${TEST_NAME}.cpp qmain.cpp)
+  add_test (${TEST_NAME} ${TEST_NAME})
+  set_property(TEST ${TEST_NAME} PROPERTY ENVIRONMENT "${CTEST_ENVIRONMENT}")
+  add_dependencies (${TEST_NAME} indicatordisplayservice)
+  target_link_libraries (${TEST_NAME} indicatordisplayservice ${SERVICE_DEPS_LIBRARIES} Qt5::Core Qt5::Test Qt5::DBus ${TEST_DEPS_LIBRARIES} ${GTEST_LIBRARIES} ${GMOCK_LIBRARIES})
+endfunction()
+add_qt_test_by_name(usb-snap-test)
+
+add_test(cppcheck cppcheck --enable=all -USCHEMA_DIR --error-exitcode=2 --inline-suppr -I${CMAKE_SOURCE_DIR} ${CMAKE_SOURCE_DIR}/src ${CMAKE_SOURCE_DIR}/tests)
 
diff --git a/tests/dbus-types.h b/tests/dbus-types.h
new file mode 100644
index 0000000..c2dfb81
--- /dev/null
+++ b/tests/dbus-types.h
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2013-2016 Canonical, Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Pete Woods <pete.woods@canonical.com>
+ */
+
+#pragma once
+
+#include <QDBusMetaType>
+#include <QtCore>
+#include <QString>
+#include <QVariantMap>
+
+typedef QMap<QString, QVariantMap> QVariantDictMap;
+Q_DECLARE_METATYPE(QVariantDictMap)
+
+typedef QMap<QString, QString> QStringMap;
+Q_DECLARE_METATYPE(QStringMap)
+
+namespace DBusTypes
+{
+    inline void registerMetaTypes()
+    {
+        qRegisterMetaType<QVariantDictMap>("QVariantDictMap");
+        qRegisterMetaType<QStringMap>("QStringMap");
+
+        qDBusRegisterMetaType<QVariantDictMap>();
+        qDBusRegisterMetaType<QStringMap>();
+    }
+    static constexpr char const* NOTIFY_DBUS_NAME = "org.freedesktop.Notifications";
+
+    static constexpr char const* NOTIFY_DBUS_INTERFACE = "org.freedesktop.Notifications";
+
+    static constexpr char const* NOTIFY_DBUS_PATH = "/org/freedesktop/Notifications";
+}
diff --git a/tests/usb-snap-test.cpp b/tests/usb-snap-test.cpp
new file mode 100644
index 0000000..309980a
--- /dev/null
+++ b/tests/usb-snap-test.cpp
@@ -0,0 +1,216 @@
+/*
+ * Copyright 2016 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Charles Kerr <charles.kerr@canonical.com>
+ */
+
+#define QT_NO_KEYWORDS
+#include <tests/dbus-types.h>
+#include <tests/glib-fixture.h>
+
+#include <src/usb-snap.h>
+
+#include <glib.h>
+
+#include <libqtdbustest/DBusTestRunner.h>
+#include <libqtdbustest/QProcessDBusService.h>
+#include <libqtdbusmock/DBusMock.h>
+
+#include <QSignalSpy>
+
+#include <gtest/gtest.h>
+
+using namespace QtDBusTest;
+using namespace QtDBusMock;
+
+inline QString qVariantToString(const QVariant& variant) {
+    QString output;
+    QDebug dbg(&output);
+    dbg << variant;
+    return output;
+}
+
+inline void PrintTo(const QVariant& variant, std::ostream* os) {
+    QString output;
+    QDebug dbg(&output);
+    dbg << variant;
+
+    *os << "QVariant(" << output.toStdString() << ")";
+}
+
+inline void PrintTo(const QString& s, std::ostream* os) {
+    *os << "\"" << s.toStdString() << "\"";
+}
+
+inline void PrintTo(const QStringList& list, std::ostream* os) {
+    QString output;
+    QDebug dbg(&output);
+    dbg << list;
+
+    *os << "QStringList(" << output.toStdString() << ")";
+}
+
+inline void PrintTo(const QList<QDBusObjectPath>& list, std::ostream* os) {
+    QString output;
+    for (const auto& path: list)
+    {
+        output.append("\"" + path.path() + "\",");
+    }
+
+    *os << "QList<QDBusObjectPath>(" << output.toStdString() << ")";
+}
+
+#define WAIT_FOR_SIGNALS(signalSpy, signalsExpected)\
+{\
+    while (signalSpy.size() < signalsExpected)\
+    {\
+        ASSERT_TRUE(signalSpy.wait());\
+    }\
+    ASSERT_EQ(signalsExpected, signalSpy.size());\
+}
+
+class UsbSnapFixture: public GlibFixture
+{
+    using super = GlibFixture;
+
+public:
+
+    UsbSnapFixture():
+        dbusMock{dbusTestRunner}
+    {
+        DBusTypes::registerMetaTypes();
+
+        dbusTestRunner.startServices();
+    }
+
+    ~UsbSnapFixture() =default;
+
+protected:
+
+    bool qDBusArgumentToMap(QVariant const& variant, QVariantMap& map)
+    {
+        if (variant.canConvert<QDBusArgument>())
+        {
+            QDBusArgument value(variant.value<QDBusArgument>());
+            if (value.currentType() == QDBusArgument::MapType)
+            {
+                value >> map;
+                return true;
+            }
+        }
+        return false;
+    }
+
+    void SetUp() override
+    {
+        super::SetUp();
+
+        dbusMock.registerNotificationDaemon();
+        dbusTestRunner.startServices();
+    }
+
+    OrgFreedesktopDBusMockInterface& notificationsMockInterface()
+    {
+        return dbusMock.mockInterface("org.freedesktop.Notifications",
+                                      "/org/freedesktop/Notifications",
+                                      "org.freedesktop.Notifications",
+                                       QDBusConnection::SessionBus);
+    }
+
+    QtDBusTest::DBusTestRunner dbusTestRunner;
+    QtDBusMock::DBusMock dbusMock;
+    QtDBusTest::DBusServicePtr indicator;
+};
+
+TEST_F(UsbSnapFixture, TestRoundTrip)
+{
+    struct {
+        const char* fingerprint;
+        const char* action_to_invoke;
+        const AdbdClient::PKResponse expected_response;
+    } tests[] = {
+        { "Fingerprint",  "allow", AdbdClient::PKResponse::ALLOW },
+        { "Fingerprint",  "deny",  AdbdClient::PKResponse::DENY }
+    };
+
+    uint32_t next_id = 1;
+    for(const auto& test : tests)
+    {
+        // Minor wart: we don't have a way of getting the fdo notification id
+        // from dbusmock so instead we copy its (simple) id generation here
+        const auto id = next_id++;
+
+        QSignalSpy notificationsSpy(
+            &notificationsMockInterface(),
+            SIGNAL(MethodCalled(const QString &, const QVariantList &)));
+
+        // start up a UsbSnap to ask about a fingerprint
+        auto snap = std::make_shared<UsbSnap>(test.fingerprint);
+        AdbdClient::PKResponse user_response {};
+        bool user_response_set = false;
+        snap->on_user_response().connect([&user_response,&user_response_set](AdbdClient::PKResponse response, bool /*remember*/){
+            user_response = response;
+            user_response_set = true;
+        });
+
+        // test that UsbSnap creates a fdo notification
+        WAIT_FOR_SIGNALS(notificationsSpy, 1);
+        {
+            QVariantList const& call(notificationsSpy.at(0));
+            EXPECT_EQ("Notify", call.at(0));
+
+            QVariantList const& args(call.at(1).toList());
+            ASSERT_EQ(8, args.size());
+            EXPECT_EQ("", args.at(0)); // app name
+            EXPECT_EQ(0, args.at(1)); // replaces-id
+            EXPECT_EQ("computer-symbolic", args.at(2)); // icon name
+            EXPECT_EQ("Allow USB Debugging?", args.at(3)); // summary
+            EXPECT_EQ(QString::fromUtf8("The computer's RSA key fingerprint is: ") + test.fingerprint, args.at(4)); // body
+            EXPECT_EQ(QStringList({"allow", "Allow", "deny", "Deny"}), args.at(5)); // actions
+            EXPECT_EQ(-1, args.at(7));
+
+            QVariantMap hints;
+            ASSERT_TRUE(qDBusArgumentToMap(args.at(6), hints));
+            ASSERT_EQ(3, hints.size());
+            ASSERT_TRUE(hints.contains("x-canonical-private-affirmative-tint"));
+            ASSERT_TRUE(hints.contains("x-canonical-non-shaped-icon"));
+            ASSERT_TRUE(hints.contains("x-canonical-snap-decisions"));
+        }
+        notificationsSpy.clear();
+
+        // fake a user interaction with the fdo notification
+        notificationsMockInterface().EmitSignal(
+            DBusTypes::NOTIFY_DBUS_INTERFACE,
+            "ActionInvoked",
+            "us",
+            QVariantList() << id << test.action_to_invoke);
+
+        // test that UsbSnap emits on_user_response() as a result
+        wait_for([&user_response_set](){return user_response_set;});
+        EXPECT_TRUE(user_response_set);
+        ASSERT_EQ(test.expected_response, user_response);
+
+        // confirm that the snap dtor cleans up the notification
+        snap.reset();
+        WAIT_FOR_SIGNALS(notificationsSpy, 1);
+        {
+            QVariantList const& call(notificationsSpy.at(0));
+            EXPECT_EQ("CloseNotification", call.at(0));
+            QVariantList const& args(call.at(1).toList());
+            EXPECT_EQ(id, args.at(0));
+        }
+    }
+}