pypizza python package

Building and installing the pypizza python package

This example illustrates how Python code can access data types written in the Xc++ language. See also the documentation of the cxPython library.

The Shape, Time and Pizza libraries are packaged into a Python Wheel file named:

    pypizza-2.0.0-cp27-cp27m-win_amd64.whl

during the install phase of CMake.

This is achieved with the following statements in MyCompany/CMakeLists.txt :

set(PIZZA_TARGETS Time Shapes Pizza)

file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/pypizza_package/pypizza/lib)

# Copy setup.py.in to pypizza_package/setup.py, allowing cmake variables like ${PROJECT_VERSION} to be used
configure_file(${CMAKE_CURRENT_SOURCE_DIR}/cmake/setup.py.in ${CMAKE_CURRENT_BINARY_DIR}/pypizza_package/setup.py)

file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/pypizza_package DESTINATION ${CMAKE_CURRENT_BINARY_DIR})

foreach(tgt ${PIZZA_TARGETS})
    add_custom_command(TARGET ${tgt} POST_BUILD
        COMMAND ${CMAKE_COMMAND} -E copy $<TARGET_FILE:${tgt}> ${CMAKE_CURRENT_BINARY_DIR}/pypizza_package/pypizza/lib)
endforeach()

install(
    CODE "execute_process( COMMAND ${PYTHON} setup.py bdist_wheel WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/pypizza_package )"
    CODE "file( GLOB wheelFiles \"${CMAKE_CURRENT_BINARY_DIR}/pypizza_package/dist/*.whl\" )"
    CODE "execute_process( COMMAND ${PYTHON} -m pip install --upgrade --no-deps --force-reinstall \${wheelFiles} )"
)

This makes use of the file MyCompany/cmake/setup.py.in and the following files under the MyCompany/pypizza_package folder:

MyCompany/pypizza_package

For convenience this installs the pypizza wheel file for you, by running the following command:

python -m pip install --upgrade --no-deps --force-reinstall pypizza-2.0.0-cp27-cp27m-win_amd64.whl

Verification that the pypizza python package has been installed correctly

As a simple check that the pypizza package has been installed correctly, do the following

Run the Python Interpreter by running the command 'python' in a terminal:

Import pypizza and pyceda and take dir(pyceda.rootnamespace) and check that the namespaces 'dt', 'pizza' and 'shapes' have been added under the root namespace.

>>> import pypizza
>>> import pyceda
>>> dir(pyceda.rootnamespace)
['FindChildNameSpace', 'FindElement', 'FindElementWithRelativePath', 
 'GetChildNameSpaceIterator', 'GetElementIterator', 'GetName', 
 'Int64', 'PyObject', 'UInt64', 'ceda', 'dt', 'pizza', 'shapes']
>>>

Type an end-of-file character (Control-D on Unix, Control-Z on Windows) then enter to exit the Python Interpreter.

Execute sample python scripts

Some sample python scripts are available under the folder MyCompany/python:

MyCompany/python
├── pypizza_package
│   ├── pypizza
│   │   └── __init__.py
│   ├── LICENSE
│   ├── README.md
│   └── setup.py
├── CMakeLists.txt
├── datetime_example.py
├── generate_pizza_jni_wrappers.py
├── open_and_close_database_example.py
├── pizza_example.py
└── shapes_example.py

You can run these sample python scripts yourself.

For example, in a terminal run datetime-example.py as follows:

python datetime-example.py

The following outputs are generated by these scripts

Script	Description	Output
open_and_close_database_example.py	Illustrates creating an (empty) database	No output is printed, a 512kB file named 'mydatabase' is created
datetime_example.py	Illustrates use of the date and time data types defined in the Time library	output
shapes_example.py	Illustrates use of the data types defined in the Shapes library	output
pizza_example.py	Illustrates use of the data types defined in the Pizza library	Writes 512kB database files named 'mypizzadatabase' and 'myreplicatedpizzadatabase'. The output generated changes each time it is run: first , second , third