Spix

Spix is a minimally invasive UI testing library that enables your Qt/QML app's UI to be controlled either via c++ code, or through an http RPC interface.

UI elements are referenced through names and paths which are robust against design changes. To click on a button you write

mouseClick("mainWindow/ok_button");

To provide an RPC test interface to your app, only add these three lines to your main(...) function:

spix::AnyRpcServer server;
auto bot = new spix::QtQmlBot();
bot->runTestServer(server);

And a test script in python could look like this:

import xmlrpc.client

s = xmlrpc.client.ServerProxy('http://localhost:9000')
s.mouseClick("mainWindow/Button_1")
s.wait(200)
s.mouseClick("mainWindow/Button_2")
resultText = s.getStringProperty("mainWindow/results", "text")
s.quit()

You can also use PyAutoGUI in combination with Spix. Have a look at the example script.

What are the applications of Spix?

The main use for Spix is to automatically test the UI of your Qt/QML application and make sure that it behaves as you expect. However, you can also use Spix as an easy way to remote control existing Qt/QML applications or to automatically generate and update screenshots for your documentation.

Requirements

• Qt (both 5 and 6 supported)
• AnyRPC

Current Features

• Send mouse events (click, move, drag/drop)
• Drop mime data from external apps
• Enter text
• Check existence and visibility of items
• Get property values of items (text, position, color, ...)
• Invoke a method on an object
• Take and save a screenshot
• Quit the app
• Remote control, also of embedded devices / iOS

Setting Up Spix

Installing AnyRPC

Spix requires AnyRPC be installed on the local machine before building. For *nix machines, AnyRPC can be built/installed using CMake:

# in a temporary directory
git clone https://github.com/sgieseking/anyrpc.git
cd anyrpc
mkdir build
cd build
cmake -DBUILD_EXAMPLES=OFF -DBUILD_WITH_LOG4CPLUS=OFF -DBUILD_PROTOCOL_MESSAGEPACK=OFF ..
cmake --build .
sudo cmake --install .

For non-*nix machines, checkout the CI install script.

Installing Spix

Spix uses cmake and can be build with the standard cmake commands once cloned:

git clone https://github.com/faaxm/spix
cd spix
mkdir build && cd build
cmake -DSPIX_QT_MAJOR=6 ..
cmake --build .
sudo cmake --install .

Change SPIX_QT_MAJOR to 5 to build against Qt5 instead of Qt6.

If you installed the dependencies (like AnyRPC) in a non-standard directory you can point cmake to it by setting CMAKE_PREFIX_PATH, so instead of cmake .. you run:

cmake -DCMAKE_PREFIX_PATH=/path/to/libs ..

Including Spix in your Qt project

If using qmake, add the following to your Qt .pro file:

QT += quick
INCLUDEPATH += /usr/local/include
LIBS += -lSpix -lanyrpc

If using CMake, add the following to your CMakeLists.txt:

find_package(Spix REQUIRED)

Update your main(...) to start the Spix RPC server:

#include <Spix/AnyRpcServer.h>
#include <Spix/QtQmlBot.h>

int main(...) {
    ...
    spix::AnyRpcServer server;
    auto bot = new spix::QtQmlBot();
    bot->runTestServer(server);
    ...
}

Finally, if you're using a QQuickView as your root window, you'll need to give it an object name in your main (otherwise the root window object name will be defined in your QML):

int main(...) {
    QQuickView view;
    view.setObjectName("root")
    ...
}

Using Spix

The easiest method of interacting with Spix is using the XMLRPC client built into python:

import xmlrpc.client

s = xmlrpc.client.ServerProxy('http://localhost:9000') # default port is 9000
s.method(<path>, <options>)
# for example:
s.mouseClick("root/Button_2")
resultText = s.getStringProperty("root/results", "text")

You can also use the XMLRPC client to list the available methods. The complete list of methods are also available in the source.

print(s.system.listMethods())
# ['command', 'enterKey', 'existsAndVisible', 'getBoundingBox', 'getErrors', 'getStringProperty', 'inputText', 'invokeMethod', 'mouseBeginDrag', 'mouseClick', 'mouseDropUrls', 'mouseEndDrag', 'quit', 'setStringProperty', 'system.listMethods', 'system.methodHelp', 'takeScreenshot', 'wait']
print(s.system.methodHelp('mouseClick'))
# Click on the object at the given path

Spix uses a slash-separated path format to select Qt objects. Selectors match against objectName or id if no object name is defined.

<root>/<child0>(/<childN>...)

Spix matches children recursivley, allowing as much flexibility as needed:

# matches any `button` that is a descendant of `root` (even subchildren)
'root/button'
# matches any `button` that is a descendant of `numberpad` which is in turn a descendant of `root`.
'root/numberpad/button'
# and so on

More specifically, Spix's matching processes works as follows:

• <root> matches a top-level QQuickWindow whose objectName (or id if objectName is empty) matches the specified string. Top-level windows are enumerated by QGuiApplication::topLevelWindows.
• <child> matches the first child object whose objectName (or id if objectName is empty) matches the specified string using a recursive search of all children and subchildren of the root. This process repeats for every subsequent child path entry.

Invoking QML methods

Spix can directly invoke both internal and custom methods in QML objects: this can be a handy way to automate interactions that Spix doesn't support normally. For example, we can control the cursor in a TextArea by calling TextArea.select:

TextArea {
    id: textArea
}

# select characters 100-200
s.invokeMethod("root/textArea", "select", [100, 200])

In addition, you can use custom functions in the QML to implement more complicated interactions, and have Spix interact with the function:

TextArea {
    id: textArea
    function customFunction(arg1, arg2) {
        // insert QML interactions here
        return {'key1': true, 'key2': false}
    }
}

# invoke the custom function
result = s.invokeMethod("root/textArea", "customFunction", ['a string', 34])
# prints {'key1': True, 'key2': False}
print(result)

In general Spix will attempt to coerce the arguments and return value to the correct types to match the method being invoked. Valid conversion are listed under the QVariant docs. If Spix cannot find a valid conversion it will generate an error.

Item {
    id: item
    function test(arg1: bool) {
        ...
    }
}

# ok
s.invokeMethod("root/item", "test", [False])

# argument will implicitly be converted to a boolean (True) to match the declaration type
s.invokeMethod("root/item", "test", [34])

# no conversion from object to boolean, so an error is thrown
s.invokeMethod("root/item", "test", [{}])

Using generic/custom command

You can register your own commands in your C++ Application. It could be useful for Example to reset your hole Application.

Register the Commands in your C++ Code:

    ...
    spix::AnyRpcServer server;
    server.setGenericCommandHandler([](std::string command, std::string payload) {
        // do whatever needs to be done
    });
    ...

Now you have all capabilities that the Application has. The Payload handling must be done by your own.

You can call this in Python like this:

s.command('reset', 'now')

Two modes of operation

In general, Spix can be used in two ways, which are different in how events are generated and sent to your application:

Generate Qt events directly

You can use Spix to directly create Qt events, either from C++ as a unit test, or from an external script via the network through RPC. Since the Qt events are generated directly inside the app, and do not come from the system, the mouse cursor will not actually move and interaction with other applications is limited. On the plus side, this mechanism is independent from the system your app is running on and can easily be used to control software on an embedded device via the network (RPC).

Generate system events externally

In this case, Spix is not generating the events itself. Instead, you use a script to query Spix for the screen coordinates of qt objects and then generate events on the system level through other tools. One option is to use python together with PyAutoGUI for this, as is done in the RemoteCtrl example.