Question

I have a twenty byte hex hash that I would like to store in a django model. If I use a text field, it’s interpreted as unicode and it comes back garbled.

Currently I’m encoding it and decoding it, which really clutters up the code, because I have to be able to filter by it.

def get_changeset(self):     return bin(self._changeset)  def set_changeset(self, value):     self._changeset = hex(value)  changeset = property(get_changeset, set_changeset) 

Here’s an example for filtering

Change.objects.get(_changeset=hex(ctx.node())) 

This is the approach that was recommended by a django developer, but I’m really struggling to come to terms with the fact that it’s this ugly to just store twenty bytes.

Maybe I’m too much of a purist, but ideally I would be able to write

Change.objects.get(changeset=ctx.node()) 

The properties allow me to write:

change.changeset = ctx.node() 

So that’s as good as I can ask.

Answer 1

I’m assuming if you were writing raw SQL you’d be using a Postgres bytea or a MySQL VARBINARY. There’s a ticket with a patch (marked ‘needs testing’) that purportedly makes a field like this (Ticket 2417: Support for binary type fields (aka: bytea in postgres and VARBINARY in mysql)).

Otherwise, you could probably try your hand at writing a custom field type.