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Hi Chris,

That's helping a lot, thanks for all of this!

Regards,

-- 
Arnaud Morin

On 23.10.19 - 16:26, Chris Dent wrote:
> On Tue, 22 Oct 2019, Arnaud Morin wrote:
> 
> > I am trying to configure apache as a WSGI.
> > Is there any other documentation than this:
> > https://docs.openstack.org/nova/stein/user/wsgi.html
> > 
> > Is there any recommendations?
> 
> There are a lot of options, and which you use can mostly come down
> to personal preference and other aspects of your environment. For
> example, if you're running in a kubernetes environment, using apache
> at all can be overkill: the nova-api container(s) can expose an http
> service which are reached through the ingress. Adding apache in that
> environment would mean you had proxy -> proxy/apache -> service. If
> you're trying save some space, that's overkill.
> 
> However, if what you want is some kind of combination where apache
> is in front of the nova-api you have three basic options:
> 
> * Use apache plus mod_proxy to talk to the eventlet driven
>   `nova-api` process.
> 
> * Use apache plus mod_wsgi to talk to the `nova-api-wsgi` application,
>   probably using WSGIDaemonProcess.
> 
> * Use apache plus mod_proxy_uwsgi to talk to the `nova-api-wsgi`
>   application, itself being run by uwsgi, where the uwsgi process
>   is started and managed by something like systemd or uwsgi emperor
>   mode.
> 
> If you use either of the latter two you need to be aware of a
> potential issue with eventlet as described in the release notes for
> stein: https://docs.openstack.org/releasenotes/nova/stein.html#known-issues
> 
> There's some boilerplate documentation for using mod wsgi and uwsgi for
> various projects. Here's the one for zun:
> 
>     https://docs.openstack.org/zun/train/contributor/mod-wsgi.html
> 
> There's some documentation in placement which has links to the
> changes that added placement in devstack, first using mod_wsgi and
> then using uwsgi:
> 
>     https://docs.openstack.org/placement/latest/install/
> 
> That can be a useful guide, just remember to replace placement names
> with the corresponding nova names. Where placement uses
> `placement-api`, nova wants `nova-api-wsgi`.
> 
> There are many options for how to do this, so there's no
> straightforward cookiecutter answer. The important thing to remember
> is that `nova-api-wsgi` is a standard WSGI application and there are
> all kinds of resources on the web for how to host a WSGI application
> on a variety of web servers in various ways. Things you learn about
> handling a WSGI application of one sort can be transferred to others
> (with the important caveat about nova and eventlet described above).
> 
> My current way for doing this kind of thing is to run uwsgi in a
> container and then have a proxy talk to that container. See
> https://github.com/cdent/placedock for how I've done this with
> Placement. If there's no container involved, I simply run uwsgi
> standalone.
> 
> -- 
> Chris Dent                       ٩◔̯◔۶           https://anticdent.org/
> freenode: cdent