OSDC 2008 is a conference run by open source developers, for developers and business people. It covers numerous programming languages across a rangeof operating systems, and related topics such as business processes, licensing, and strategy. Talks vary from introductory pieces through to the deeply technical. This year we have an exciting selection of presenters and keynote speakers including:

• Larry Wall, the creator of Perl
• Chris DiBona, Open Source Programs Manager for Google
• Andrew Tridgell, Founder, Samba Team
• Anthony Baxter, Python Evangelist
• Pia Waugh, Consultant, Waugh Partners

Check out the draft program: http://www.osdc.com.au/2008/papers/

Please visit http://www.osdc.com.au/2008/registration/ to register. Early bird registration closes on the 27th October, 2008.

For more information about this event, please visit: http://www.osdc.com.au/.

Instructions: Take a picture of yourself right now. Don’t change your clothes, don’t fix your hair - just take a picture. Post that picture with NO editing. Post these instructions with the picture.

Hat tip - Steve Holden and Simon Brunning

It turns out that there is a small difference between the default configuration for Vimoutliner and the way I set up my Vim environment. By convention extension scripts for Vim are stored in a ‘plugin’ directory under your Vim home (which is ~/.vim by default) and that is where, amongst others, I had place vo_checkbox.vim and vo_hoist.vim. But for reasons known only to itself I have just discovered that Vimoutliner looks for extension scripts in a directory called ‘plugins’ (notice the plural). So a quick directory add and a couple of svn move’s later and I was back in business.

• Numerous renames to more fully comply with PEP-8
• Added numerous tests, full details in the CHANGELOG.txt file
• Added an ‘enabled’ flag to table constraints (except in the MySQL module, because that database doesn’t support them)
• Added support for column defaults in Oracle
• Added a ‘table_name’ attribute to the schema.Trigger class
• Removed main and usage functions from each module that shouldn’t be imported

Please download, install and enjoy. Bug reports or tumultuous praise to the usual address please.

My Macbook had not been well since last week. Basically the fan was running constantly which apart from the annoying noise meant that the battery drained in about 30 minutes. Having had my last machine in and out of third party Apple certified repair shops for most of it’s short and inglorious life I was prepared for the worst. I migrated all of my files and data onto a borrowed work laptop and headed to George Street resigned to losing my machine for a couple of weeks.

I walked out half an hour later with a fully working machine. Admittedly the fault was minor and easily fixed but with my last machine each of the repair centres I used had a mandatory (usually two week) period where they kept the machine before looking at it. My experience in George street was about fifteen minutes.

All hail the shiny new store. Now to see if they can fix the internal microphone.

I’ve logged a support ticket but thought I should mention it here in case anyone else sees the same issue.

When I tried to log in after the database upgrade the login page just kept re-directing back to itself. The main page of this blog was showing, but with an error message stating (in part) - “error in akismet.php on line 487″.

After a little checking around I discovered that Akismet (the WordPress spam fighting plugin) needed to be upgraded at the same time as the core WordPress code and hadn’t. The old version (2.1.4) is not compatible with the latest WordPress release and needed to be upgraded (to 2.1.6). A simple workaround was to download and install the latest version of Akismet by hand so it wasn’t a huge problem, but it would have been nice if the WordPress Subversion repository had been updated to reflect the change.

Update: OK, it’s probably me. A fresh checkout of WordPress (release 2.6 or 2.5) comes complete with the correct version of the Akismet plug in. It must have a problem with my ‘svn switch‘ that I didn’t catch.

Strangely enough I was talking about this with a colleague this very afternoon. My thesis was that data is generated by applications but should be considered independent of them. Treat your data carefully and you have a treasure trove of information that defines your organisation. Take an application centric view of the world and you end up with a load of blobs that are only meaningful in the context of your application code. If you can ever find a way to free your information you can find so many different ways of viewing, interpreting and analysing it.

In essence this is the excitement that surrounds mashups and the value that shown in sites like Chicago Crime and My Society. Expose the data and then marvel at what happens.

As I said in a (remarkably brief) presentation that I gave tonight - I’m Andy and I’m a data manager. If I can ever find a way of making a living taking data, turning it into information and making it available in new and interesting ways I guarantee that I will quit my day job in a heartbeat.

Call for Papers
Open Source Developers’ Conference 2008
2nd - 5th December 2008, Sydney, Australia

The Open Source Developers’ Conference 2008 is a conference run by open source developers, for developers and business people. It covers numerous programming languages across a range of operating systems, and related topics such as business processes, licensing, and strategy. Talks vary from introductory pieces through to the deeply technical. It is a great opportunity to meet, share, and learn with like-minded individuals.

This year, the conference will be held in Sydney, Australia during the first week of December (2nd - 5th). If you are an Open Source maintainer, developer or user, the organising committee would encourage you to submit a talk proposal on open source tools, solutions, languages or technologies you are working with.

For more details and to submit your proposal(s), goto: http://osdc.com.au/2008/papers/cfp.html

If you have any questions or require assistance with your submission, please don’t hesitate to ask!

We recognise the importance of Open Source in providing a medium for collaboration between individuals, researchers, business and government. In recognition of this and ensure a high standard of presentations, we intend to peer-review all submitted papers.

OSDC 2008 Sydney (Australia) - Key Program Dates:

30 Jun - Initial proposals (short abstract) due
21 Jul - Proposal acceptance
15 Sep - Accepted paper submissions
13 Oct - Reviews completed
27 Oct - Final paper submission cutoff

For all information, contacts and updates, see the OSDC conference web site at http://osdc.com.au/2008/

Also if you are interested in sponsoring, please see: http://www.osdc.com.au/2008/sponsors/opportunities.html

Is there a Python idiom for accepting either a file name or a file object as a function parameter?

The closest I can get is this;

def my_function(file_name_or_object):
    try:
        open(file_name_or_object)
    except TypeError:
        file = file_name_or_object
    return file

Any improvements on this are more than welcome.

1. Date support in relational databases is insane, or at the best inconsistent.

As far as I can tell the ANSI SQL-92 standard defines date, time, interval and timestamp data types. Which doesn’t help when SQL Server only implements something called ‘datetime’ - at least I think so, have you tried accessing any sort of manual for a Microsoft product online? Blimey, I thought billg had embraced this web thing years ago. Oracle has the ‘date’ data type (which is actually a time stamp) and MySQL, well they’ve gone and outdone everyone by implementing DATETIME, DATE, TIMESTAMP, TIME, and YEAR.

2. The Python DB-API does not cope with date data type ambiguity well.

When it comes to the date question the Python DB-API states (and I quote) ” … may use mx.DateTime”, which if you ask me isn’t much of a standard. This needs to change so that all DB-API modules return consistent datetime objects, not such a big issue as datetime has been part of the standard library since, what, Python 2.3?

Sadly even if we fix this it won’t work with Sqlite as it doesn’t consistently support data typing. In my experiments regardless of what sort of date you insert into the database you get a unicode string back. Don’t believe me? Try this in Python 2.5;

>>> from sqlite3 import dbapi2
>>> db = dbapi2.connect('test_db')
>>> cursor = db.cursor()
>>> cursor.execute('create table date_test (id integer not null primary key autoincrement, sample_date DATE NOT NULL)'
>>> stmt = "INSERT INTO date_test (sample_date) VALUES (?)"
>>> cursor.execute(stmt, (1234, ))
>>> import datetime
>>> cursor.execute(stmt, (datetime.date(2008, 3, 10), ))
>>> cursor.execute(stmt, ('My name is Earl', ))
>>> db.commit()
>>> cursor.execute("SELECT * FROM date_test")
>>> results = cursor.fetchall()
>>> for item in results:
...     print item[1], type(item[1])
1234 
2008-03-10 
My name is Earl 
>>>

But note that it is fine for integers.

3. The people writing the Python standard library modules are on crack.

Outside of the database world and within the batteries included Python standard library some modules use datetime, others time and there are even uses of calendar.

O.K. I’ll accept that maybe the module authors aren’t on full strength crack, because the time module just exposes underlying posix functions. But the people who wrote those were on something strong and hallucinogenic. I table the following function signatures from section 14.2 of the Python Library Reference 2.5 as an example;

strftime(format[, t ])
strptime(string[, format ])

This has bitten me twice in the last twenty four hours and frankly I’m not happy.

I appreciate that there are historical reasons for having inconsistent function signatures but can someone please fix this in Python 3.0. All we need is a single module that can access the underlying system clock and then convert between a number of different representations of that and other epoch driven dates. How hard can it be? As far as I can tell this is not part of the proposed standard library re-organisation. I think it should be.