Sorry for the slow reply -- just getting back from vacation.
I've never tried to get System.base_url to work by putting it in environment files, but so long as the load order is correct, I would think it might be possible. I do notice in the wagn.rb file posted above that though System.base_url is commented out at the top, it is set again at the bottom of the file. Could that be the problem?
More broadly, wagn does have a better tested solution for running multiple wagns from the same installation, but at present it will only work in postgres. To set this up, you will need to create a separate postgres "schema" for each wagn, and to put a dummy wagn database in the public schema. Then you populate the multihost_mappings table in the public schema to manage the various hosts and where they point. If you're using apache, you can do all of this with a single virtual host.
We haven't documented this extensively because we are not yet sure we want to make a long-term commitment to supporting this approach, but the wagns hosted by grasscommons use this system, so it could certainly be considered robust at present.
With the approach you describe, I would be particularly worried about caching issues. You might find that the cache cannot correctly distinguish between cards with the same name on different wagns.
my wagn.rg contains just one commented System.base_url definition. The second definition is in the env file.
My solution might have a cache problem. The mutihost approach is not documented in detail. That means I have to change to seperate installations per wiki. What a pity.
--dermicha.....Fri Aug 05 14:59:36 -0700 2011
Are you using PostgreSQL? I might be willing to write up some quick docs if I know it will be used.
Looking more closely at the cache situation, I think you may be able to get your solution to work, because the cache is individualized based on the base_url. I would also set System.wagn_name separately for each env.
As for the base_url not working, my first step would be to print some logging info so that you can figure out when the base_url is getting set (and why it's not sticking). Could be a load order issue.
--Ethan McCutchen.....Fri Aug 05 15:11:18 -0700 2011
Currently I use MySQL. But I would also use Postgres.
I will give wagn 1.7.0 and MySQL based on my multi-env approach a second chance.
I have now set log level to debug an could no hints about System.base_url.
Does that:
Cache read: localhost:3000/testSystem/131258517392ck/*star
Cache read: localhost:3000/testSystem/131258517392ck/*star+*read
Cache read: localhost:3000/testSystem/131258517392ck/search+*type
mean that System.base_url was not set? I didn't set it to localhost:3000.
--dermicha.....Sun Aug 07 07:11:57 -0700 2011
you might try commenting out the base_url line in sample_wagn.rb, which is loaded for setting defaults.
--Ethan McCutchen.....Sun Aug 07 10:37:44 -0700 2011
No. That does not have any effect.
I see a redirect basing on System.base_url only working when I use production enviroment. in any other enviroments (e.g. development or my own envs) System.base_url will be ignored. For me it looks like a hard dependency to rails production enviroment. Or there is an magic property that is set by rails in production env and had to be set manually in any other enviroments to activate redirection.
--dermicha.....Wed Aug 10 13:59:36 -0700 2011