The document discusses using Django on the Jython platform. Some key points: - Jython allows running Python code on the Java Virtual Machine (JVM), compiling Python to Java bytecode. This enables using Java libraries and deploying Python applications on Java application servers. - Django projects can be packaged and deployed as a WAR (Web ARchive) file, making use of the standard Java web application deployment format. - Using Django on Jython provides performance and scalability benefits from running on the JVM and ability to integrate with the large Java ecosystem, like databases and libraries.

1. Django on Jython Leo Soto

2. Not exactly “ Summer of Code” but... ...worked incredibly well! And that's why I'm here :)

3. Why Django on Jython ? Integration Deployment Performance

4. Jython

5. Jython Implementation of Python Compiles to Java bytecode No foo.pyc It's foo$py.class

6. Jython Makes Java look like Python And Python like Java to Java programs No GIL, no ref counting

7. >>> from __future__ import GIL Traceback (most recent call last): ... SyntaxError: Never going to happen! (<stdin>, line 1)

8. State of Jython 2.5 99.4% of ~5700 test cases passing ~20% faster on PyStone [FWIW] 2.5 alpha 2 last weekend for DjangoCon September/October beta December/January final

9. Java - What We Like Great systems programming language Well-defined memory, concurrency model Standard libraries - concurrent collections

10. Java Ecosystem Excel, thru Apache POI support of OLE Full text search with Lucene Scalability with Hadoop, Hbase Scala, JRuby, Rhino...

11. Biggest Benefit Just use what is good out there in the Java ecosystem

12. Now...

13. Why in the name of... J2EE was a big, horrible mistake But lessons have been learned And it’s possible to use that infrastructure

14. “We write Java so you don’t have to.”

15. Combination In Python code: Django app framework Models, templates, forms Business logic - as complex as necessary In Java code (optional) Performant infrastructure

16. Deployment Options Java App Servers!

17. modjy Servlets <=> WSGI

18. WAR! Web ARchive format Standard deployment of Java webapps Just a zip file with a standard directory layout

19. A Django WAR: jython manage.py war --include-java-libs=XXX.jar

20. WAR format for DoJ |-- WEB-INF | |-- lib ← JDBC driver | `-- lib-python | |-- Lib ← Python Std. library | |-- django | |-- doj | |-- modjy-django | `-- mysite ← Your code! `-- media ← (and media files)

21. What’s missing PIL! so no Photolog Oracle, MySQL, SQLServer backends But that’s easy zxJDBC: JDBC <=> DB-API

22. Django Backend Dev Features Operations Client Creation and Introspection Validation Wrapper

24. Demo

25. Thanks!