how to add middleware

[Jason]

How do I add custom middleware to Pyramid. I have a function add_auth(app) in myapp.lib.auth and I have tried setting my [pipline:main] section to:

[pipeline:main]

pipeline =

    egg:WebError#evalerror

    egg:myapp.lib.auth.add_auth

    sales

I also tried egg:myapp.lib.auth:add_auth, egg:myapp.lib.auth#add_auth. I have also tried the same making add_auth a class that accepts the app argument to __init__. I tried those combinations without the egg: as well. Nothing seems to work to add custom middleware. I always get distribution not found error. 

Is there any documentation on how to add custom middleware?

I did a search on google for "pipeline site:docs.pylonsproject.org" but none of the pages show how to add custom middleware to an application.

[Thomas G. Willis]

If you want to do it through the ini file, then you should read up on PasteDeploy. 

http://pythonpaste.org/deploy/#paste-filter-app-factory

[Jason]

PasteDeploy's documentation helped, but it was still a little confusing. To add a custom middleware you have to write it like:

def auth_filter_factory(global_conf):

    def add_auth(app):

        # make wsgi app

        return app

    return add_auth

and then in the INI file:

[pipeline:main]

pipeline = egg:WebError#evalerror auth sales

[filter:auth]

paste.filter_factory = sales.lib.auth:auth_filter_factory

Any additional keys under [filter:auth] will be sent to auth_filter_factory as keyword arguments

--

Jason