EuroPython 2013: Cross-Platform Apps Dev in Python

https://ep2013.europython.eu/conference/talks/developing-open-source-multi-platform-applications-with-python-in-2013

With the emergence of mobile platforms such as IOS and Android, building Applications (Apps) has again been trendy for the last three to five years within the developers’ community. The birth of Apps stores for traditional platforms such as Mac OS X, Windows 8 and Ubuntu also favors a re-birth of cross-plateform desktop applications development. Gmvault is a standalone open-source application allowing users to backup and restore their Gmail mailbox (www.gmvault.org). Within this talk, the Gmvault creator will detail based on his experience, why he thinks that the Python platform is a mature candidate to be used for developing cross-platform applications. He will detail the strengths of Python, to develop multi-platform applications in addition to its intrinsic qualities, like: the abstraction of Python OS oriented libraries (os, file) making Python agnostic of the hosting platform, the capacity to interface with any c/c++ library, the dedicated OS system APIs (win32, registry, …) to deal with OS specificities. He will also go through the current Python weaknesses when one wants to develop multi-platform applications like the complete lack of mature and well maintained desktop packaging and deployment libraries for Windows and Mac OS X, the limited number of available multi-platform GUI toolkits or the lack of libraries interfacing with the different OS scheduling or notification features. He will finally share his experience on building an open-source application and especially what the developer will get out of this journey if he is brave enough to embark on this adventure.

Transcript

1. Cross-Platform Apps Dev in Python 2013: Back to the desktop http://www.gmvault.org EuroPython 2013
2. Guillaume Aubert : Creator of Gmvault : @zoobert : gaubert http://www.gmvault.org
3. Future of Python ? - Have to seriously think on the future of Python - Strong in the scientific community - Web Backend: Was and still strong but • HTML5/javascript will soon everwhere - Server Side, New comer: go lang, ... - Python doesn't want to be the next Fortran
4. Find new areas of growth for Python
5. Develop Desktop Cross Platform Apps
6. Many distribution platforms
7. Many distribution platforms
8. Many distribution platforms
9. Why is Python a valid candidate ?
10. - Interpreter identically running on the main platforms Win 32, Windows 8, Mac OSX and Linux Develop once run everywhere Hmm reminds me of something ! Python fulfilling 90's Promise
11. Can access OS functions - Support for Posix API on all systems - Filesystem API is the C one: simplest abstraction to a file system • os module for operations on files and dirs • os.path to do path resolution - System Environment variables supported • important for easily configuring your app • os.env("HOME")
12. Posix Included - Support for Processes • fork, execv, spawn Support for IPC • Pipes, shared memory - Support for Threads • ok to run a GUI loop and associated treament in parallel
13. But not always sufficient ! - Underlying file systems differ and Windows Filesystem is ... troublesome - Stupidly slow when it comes to read directory contents - On Linux: 2 sec to list 250K emails over 50 Dirs while more than 30 sec on Win • Gmvault has a lazy read function and caching strategy for the emails
14. Extend it if needed - Can access the C/C++ libs on Win and Lin • call up DLLs and C libs - ctypes is excellent for prototyping - Can access objC libs with pyobjc - Means that you will not be cross-plateform
15. What is missing ?
16. Graphical Interfaces - Cross plateform - Native UI - Powerful (multiple widgets) - lively community around these frameworks
17. But ...
18. The Obvious • Build UI with what you know • Don't want to learn a new framework • Easier to transform your App in a SaaS
19. Python - HTML5 Bridge http://www.tidesdk.org
20. nodewebkit: My Choice • use chromium for rendering • use nodejs for the UI backend • Python for the business part • more DIY but more freedom +
21. Packaging Tools - Packaging is critical to provide an easy install - PyPi with pip + virtualenv is fantastic • Why do I have to install setuptools (ez_setup.py) to install pip - This is for Nerds and Geeks - Can offer that kind of packaging for Linux
22. Packaging Tools (ctd.) - For Windows, you need a self-contained package - You can package python.exe in your distribution but it is tedious - Build an executable including all Python assets (interpreter, modules) - This is done with py2exe (http://www.py2exe.org/)
23. Packaging Tools (ctd.) - py2exe is dying - Not been updated since 2008 - You need to be a Google search guru to find the documentation
24. Packaging Tools Need somebody in this room to start working on it !! The Python community needs you !
25. Open Source Dev Experience
26. Start Open Sourcing now http://www.gmvault.org
27. Start Open Sourcing now Kill Your Television (Ned's Atomic Dustbin)
28. Open Source Now ! - Your own personal tailored training - Your CV will shine - Incredibly rewarding - Unique sense of freedom and control - Unique ideas could allow you to be financially sucessful
29. Open Source Success Triumvira
30. Open Source Success Tips
31. Hacker News
32. Thank you ! Questions ?
33. No libs for Notification • No cross-platform python lib for that
34. nodewebkit apps example