On Thu, May 6, 2010 at 5:12 AM, Chris Withers chris@simplistix.co.uk wrote:

Hi All,

Here's the scenario; we have per-project buildouts, but where and how people lay out their checkouts and how they access svn (svn:// versus http:// versus https:// externally).

Buildout lends itself to this flexibility by having the per-project buildouts use templated values, with those values being specified in ~/.buildout/default.cfg

...except, this doesn't seem to work for buildout:extends.

For example, here's a project buildout:

[buildout] extends = ${buildout:base_location}/versions/repoze.bfg-1.2-versions.cfg ...

And here's what's in ~/.buildout/default.cfg:

[buildout] base_location = /Users/chris/LocalSVN/base

...but, the normal ${} substitution doesn't appear to happen in the extends line, so I get the following error:

IOError: [Errno 2] No such file or directory: '/Users/chris.withers/LocalSVN/demoapp/${buildout:base_location}/versions/repoze.bfg-1.2-versions.cfg'

What am I doing wrong?

Nothing. There are certtain stages of processing where variable substitution isn't done. This is, in part because the variable database hasn't been established yet.

I think the situation needs to be improved. At least, I think variable substitutions could reflect the database as it exists at the time of a variables use. This would allow extends to use variables defined on the command line, in default.cfg and in files already read. Of course, the restrictions that remain should be clearly documented.

How can I achieve my aims with buildout 1.4.3 or later?

I expect this will work correctly in a later version of buildout. :)

Jim