[long] bzr with wsgi and gunicorn vs Pylons (paste)

[Adrien Saladin]

Hi,

I'm playing a little bit with smart bazaar wsgi servers and I'm
currently trying to integrate the bzr+http protocol in some Pylons
application.

I have read the smart server documentation found here:
http://doc.bazaar.canonical.com/latest/en/user-guide/http_smart_server.html
First I had to adapt a little bit the wsgi example to be served with
gunicorn instead of apache, so I put is there for comments and
eventually to help other wsgi newbies like me:


###     server.py              ###
from bzrlib.transport.http import wsgi

def application(environ, start_response):
+    environ['REQUEST_URI']=environ['PATH_INFO']

    app = wsgi.make_app(
        root="/home/adrien/bzr/",      #<-- where I put bazaar branches
        prefix="/bzr/",                      # <-- first part of the URL
        readonly=True,
        enable_logging=True)

    ret =  app(environ, start_response)
    return ret
#####################
# To run the server type:
# $ gunicorn server  -b localhost:9000


The only change here is that the environment variable REQUEST_URI is
not set by gunicorn (neither by Pylons/paste).

Now I can work with my foo branch with commands like:
$ bzr branch bzr+http://localhost:9000/bzr/foo

note that using http instead of bzr+http results in a 404 error.

Have I done things correctly up to now ?

Now comes my problem, when I try to interface this server in a Pylons
application.
First I created a new controller called "bazaar". Then I replaced the
code for this controller by this:

##########  (extract of) controllers/bazaar.py
def BazaarController(environ, start_response):
    environ['REQUEST_URI']= environ['PATH_INFO']

    app = wsgi.make_app(
            root="/home/adrien/bzr/",
            prefix="/bazaar/",             #<-- now using /bazaar/ as
the root URL
            readonly=True,
            enable_logging=False)

    ret = app(environ, start_response)
    print "@@@returns@@@: ",ret

    return ret
	
#################

I also modified the config/routing.py for the special URLs from
bzr+http protocol:

+ map.connect("/bazaar", controller="bazaar")
+ map.connect("/bazaar/{branchname:.*?}", controller="bazaar")


Now when I test this new setup, I have the following error from bzr (client):
$ bzr branch bzr+http://localhost:5000/bazaar/foo
bzr: ERROR: Invalid range access in
http://localhost:5000/bazaar/foo/.bzr/smart at 0: Can't read 28 bytes
across range (0, 25)

And from the server:
14:45:32,078 DEBUG [worker 4] [routes.middleware] Matched POST
/bazaar/foo/.bzr/smart
14:45:32,078 DEBUG [worker 4] [routes.middleware] Route path:
'/bazaar/{branchname:.*?}', defaults: {'action': u'index',
'controller': u'bazaar'}
14:45:32,078 DEBUG [worker 4] [routes.middleware] Match dict:
{'action': u'index', 'controller': u'bazaar', 'branchname':
u'foo/.bzr/smart'}
@@@returns@@@:  ['error\x01incomplete request\n']
14:45:32,087 DEBUG [worker 5] [routes.middleware] Matched POST
/bazaar/foo/.bzr/smart
14:45:32,088 DEBUG [worker 5] [routes.middleware] Route path:
'/bazaar/{branchname:.*?}', defaults: {'action': u'index',
'controller': u'bazaar'}
14:45:32,088 DEBUG [worker 5] [routes.middleware] Match dict:
{'action': u'index', 'controller': u'bazaar', 'branchname':
u'foo/.bzr/smart'}
@@@returns@@@:  ['error\x01incomplete request\n']

So if I correctly understand, the bzrlib wsgi application returns
"error\x01incomplete request". However I don't see what to do next to
understand what happens.
This looks more or less Pylons specific but maybe bzr or wsgi experts
here can help me understand what makes bzrlib.transport.http.wsgi
unhappy.

Thanks,
Adrien