PyConZA 2013: "Enterprise Python" by Travis Pawley

A quote from a fellow Python coder... "Coding in Python is like writing poetry"

My talk will be about how to bring python into the corporate / enterprise world. With over 10 years of Python and Django experience, I wish to share my tribulations and exaltations in how I managed to incorporate Python and Django into the companies I've worked for, deploying systems all over the world.

Some of the high level topics:

- How to get buy in from your executive management team
- Lack of Python developers, J2EE, PHP and other resource pools
- Integrating with existing legacy databases
- System integration, and interfaces best practice
- SQL vs No SQL
- Horizontal scaling and cloud computing

Some of the technologies I'll be discussing:

- buildout and virtualenv: Dependency Management
- django: Web Development Framework
- south: Database schema management and migration
- nose: Testing
- fabric: Deployment
- sphinx: Documentation (ReadySET)
- celery: Enterprise Integration Patterns
- rest-framework / piston: Web API
- twitter-bootstrap: HTML5, CSS3, JavaScript Development Framework
- responsive-themes: Supporting mobile devices

This talk is about using best practices, awesome libraries and the strength of existing systems and developers to rapidly deploy stable production systems into your company.

Transcript

1. Enterprise Python __author__ = “Travis Pawley” Monday 04 November 13
2. Python >>> import __hello__ Hello world... >>> from __future__ import braces File "<stdin>", line 1 SyntaxError: not a chance Monday 04 November 13
3. Python >>> import this The Zen of Python, by Tim Peters Beautiful is better than ugly. Explicit is better than implicit. Simple is better than complex. Complex is better than complicated. Flat is better than nested. Sparse is better than dense. Readability counts. Special cases aren't special enough to break the rules. Although practicality beats purity. Errors should never pass silently. Unless explicitly silenced. In the face of ambiguity, refuse the temptation to guess. There should be one-- and preferably only one --obvious way to do it. Although that way may not be obvious at first unless you're Dutch. Now is better than never. Although never is often better than *right* now. If the implementation is hard to explain, it's a bad idea. If the implementation is easy to explain, it may be a good idea. Namespaces are one honking great idea -- let's do more of those! Monday 04 November 13
4. Python >>> import antigravity Monday 04 November 13
5. Enterprise • Standards (aka Red Tape) • Support (SLA’s) • Language toolkits • Java, Oracle. • Top down Monday 04 November 13
6. Challenges • Python not a real language • Open source, no support • Doesn’t scale • Not fast enough • Hard to find Python developers Monday 04 November 13
7. Development vs. Operations java.lang.NullPointerException at org.apache.struts.action.ActionServlet.parseModuleConfigFile(ActionServlet.java:705) at org.apache.struts.action.ActionServlet.initModuleConfig(ActionServlet.java:670) at org.apache.struts.action.ActionServlet.init(ActionServlet.java:329) at javax.servlet.GenericServlet.init(GenericServlet.java:212) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:981) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4045) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4351) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardHost.start(StandardHost.java:719) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443) at org.apache.catalina.core.StandardService.start(StandardService.java:516) at org.apache.catalina.core.StandardServer.start(StandardServer.java:710) at org.apache.catalina.startup.Catalina.start(Catalina.java:566) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443) at org.apache.catalina.core.StandardService.start(StandardService.java:516) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413) Monday 04 November 13
8. Example - Wine Farm • Have existing corporate website • Consulting company more interested in consuming product than supporting site • Internally take over and integrate Monday 04 November 13
9. New Project - buildout bootstrap.py buildout.cfg fabfile.py etc/ src/ media/ docs/ static/ templates/ bin/ develop-eggs/ eggs/ parts/ downloads/ Monday 04 November 13
10. Legacy Systems - inspectdb bin/django inspectdb --database=_wordpress > models.py Monday 04 November 13
11. UI - twitter-bootstrap • http://getbootstrap.com/ Monday 04 November 13
12. Themes = wrapbootstrap https://wrapbootstrap.com/ Monday 04 November 13
13. Themes = wrapbootstrap https://wrapbootstrap.com/ Monday 04 November 13
14. Forms - django-crispy-forms settings.py: INSTALLED_APPS = ( ... ‘crispy_forms’, ... ) template.html: {% load crispy_forms_tags %} {{ my_form|crispy }} {% crispy my_form %} Monday 04 November 13
15. Schema Migration - south bin/django schemamigration --empty app_name initial bin/django schemamigration --initial app_name initial bin/django schemamigration --auto app_name bin/django migrate Monday 04 November 13
16. Messaging - celeryd settings.py: import djcelery djcelery.setup_loader() BROKER_URL = 'amqp://guest:guest@localhost:5672/' Monday 04 November 13
17. REST - djangorestframework • http://django-rest-framework.org Monday 04 November 13
18. Testing - django-nose INSTALLED_APPS = ( ... 'django_nose', ... ) TEST_RUNNER = 'django_nose.NoseTestSuiteRunner' --with-fixture-bundling Monday 04 November 13
19. Mocking - mock from mock import Mock from pycon.internal.interfaces.sap import SapClient SapClient.connect = Mock() SapClient._call = Mock(return_value=True) SapClient.close = Mock() Monday 04 November 13
20. Documentation - sphinx • http://readysetsphinx.tigris.org/ • Based on readyset • reStructured Text Monday 04 November 13
21. Deployment - fabric from fabric.api import env, local, settings, abort, run, cd env.hosts = ['myserver1', 'myserver2'] ROOT = '/var/www/pyconza/' def test(): with cd(ROOT): local('bin/django test') def deploy(): with cd(ROOT): run('git pull') run('bin/buildout -vN') run('bin/django migrate') Monday 04 November 13
22. Django - MongoDB • Clustering and Sharding • Great model support • Behind Django release • Loose your DBA’s Monday 04 November 13
23. Cloud - libcloud • http://libcloud.apache.org/ • Amacon EC2, Rackspace Cloud, Google Compute Engine, vCloud, CloudStack, OpenStack Monday 04 November 13
24. Environment • PyCharm • Inkscape • Visual Paradigm Monday 04 November 13
25. Mentions • scipy, numpy and pandas • requests • django-spurl • django-polymorphic • python-dateutil • suds • unipath Monday 04 November 13