No! Bad Pony!
Dr Russell Keith-Magee
DjangoCon 2009

wotnews.com.au
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wearehunted.com

how is ponny formed?

Genesis of the pony

Cal Henderson @ DjangoCon2008

What does it mean?

What is a pony?

What turns an idea
into a bad pony?

It’s an idea that...
• Is just plain wrong
• Is impractical
• Isn’t a good fit for Django’s design
• Takes the project in the wrong direction
• Comes without an offer of assistance

Ideas that are wrong

Ideas that are wrong
• Idea violates a standard or best practice
• Idea can’t be implemented
• Rusty Russell Interface Level too high
• Idea violates DRY

Impractical ideas

Impractical ideas
• A problem that doesn’t exist:YAGNI
• Changes the design contract
• Addresses a small part of larger problem
• Architecture astronauting

Design Mismatch

Replace X with Y
• Replace Django’s templates with Jinga
• Replace ORM with SQLAlchemy
• Replace test framework with Nose

Ignores the philosophy
• Add GROUP BY, HAVING to ORM
• Add variables/callables to template language
• Add AJAX to Forms

Just add a setting...
• A setting is a decision deferred
• N settings, 2 configurations
N
• Doesn’t mean we won’t add settings

Wrong direction

Feature creep
• Make development server multithreaded
• Add connection pooling

Add a backend...
• MS-SQL / DB2 / SQLAnywhere / Firebird
• New authentication schemes (LDAP)
• New serialization schemes (CSV)
• New file stores (S3)

Put another way...
• You say “Add X to core”
• We hear:
• “Here’s something else to worry about”
• “Won’t you look after this for me”
• We introduce backend APIs for a reason

The Community
• The core doesn’t have to do everything
• In fact - the core can’t do everything
• The community has an essential role here
• Blessing by core doesn’t make code better

Add X to contrib
• django-tagging
• django-registration
• django-debug-toolbar

What is django.contrib?

A collection of
optional,
defacto standard
implementations of
common patterns

Here’s a big job...
but I’d like someone else to do it (please)

Process Ponies
• Write more blog posts
• Have a weekly news summary
• Have a nightly tarball download
• Have a continuous build
• Have precompiled PDF documentation

Massive Features
• Support for multiple database connections
• Schema Evolution
• Support for non-SQL data stores

Some popular tickets

Almost certainly in 1.2
• #5390 - Signals for ManyRelatedManager
• #7052 - Problems with auth fixture loading

Possibly in 1.2
• #13 - Better related objects admin UI
• #1142 - Multiple database support
• #5833 - Custom Filterspecs
• #6845 - Model Validation

Waiting on patch
• #373 - Multi-column primary keys
• #2879 - Live test server support
• #4102 - Update of specific fields
• #6148 - Database schemas
• #6735 - Class-based generic views
• #7270 - Reverse select_related()

Waiting on design
• #2405 - FOR UPDATE in querysets
• #3011 - Extendable user auth module
• #3591 - Custom app_label/verbose_name
• #7048 - Support clearing FileFields

Waiting on decision
• #17 - Identity mapper
• #2417 - Binary DB fields
• #4604 - Session-based messages

How to get your pony

What won’t work
• Putting your name in the ticket CC
• Saying “me too” on a ticket or list thread
• Posting hyperbole on your blog
• Changing the ticket to “Milestone 1.X”
• Putting the ticket on the 1.X feature wiki

What will work
• Offer to help out
• Better still - actually help out!
• Build up karma
• Do the unglamorous stuff
• Triage, django-users, patch feedback

Don’t just write code
• Yes, code needs to be written
• It isn’t just a matter of writing a patch
• You need to be an advocate
• Best advocate is someone who is trusted

A matter of trust
• Core team has limited resources
• We need to make best use of that time
• Understand the core DVCS message:
• It’s all about trust
• It’s not about forking - it’s about merging

If you must...
• Do the research
• Demonstrate you understand the problem
• Implementation trumps idle discussion
• Maximise utility for the core team

Yes Virginia,
you can have a pony.

No Pony
!=
End of the world

Fin