Add uWSGI configuration samples

Added some samples on uWSGI config and some docs
on how to run manila with uWSGI for contributors.

Partially-implements: blueprint wsgi-web-servers-support

Change-Id: I8e68619b00255197b3d3cf6796c60d1a3a04ff36

doc/source/contributor/apache-httpd.rst

@@ -0,0 +1,79 @@
+====================================
+Running manila API with a web server
+====================================
+
+As part of the `community goals for Pike`_, manila has packaged
+a wsgi script entrypoint that allows you to run it with a real web server
+like Apache HTTPD or NGINX.
+
+This doc shows a sample of deploying manila with uwsgi
+
+Installing the API via uwsgi
+-----------------------------
+
+For this deployment we use uwsgi as a web server bound to a random
+local port. Then we configure apache using mod_proxy to forward all incoming
+requests on the specified endpoint to that local webserver. This has the
+advantage of letting apache manage all inbound http connections, but allowing
+uwsgi run the python code. This also means that when we make
+changes to manila code or configuration we don't need to restart all of apache
+(which may be running other services as well) and just need to restart the local
+uwsgi daemon.
+
+The httpd/ directory contains sample files for configuring HTTPD to run manila
+under uwsgi. To use sample configs, simply copy `httpd/uwsgi-manila.conf` to the
+appropiate location for your apache server.
+
+On RHEL/CentOS/Fedora it is::
+
+    /etc/httpd/conf.d/uwsgi-manila.conf
+
+On SLES/OpenSUSE it is::
+
+    /etc/apache2/vhosts.d/uwsgi-manila.conf
+
+On Debian/Ubuntu it is::
+
+    /etc/apache2/sites-available/uwsgi-manila.conf
+
+Enable mod_proxy by running ``sudo a2enmod proxy``
+
+On Ubuntu/Debian systems enable the site using the a2ensite tool::
+
+    sudo a2ensite /etc/apache2/sites-available/uwsgi-manila.conf
+
+This is not required on RHEL/CentOS/Fedora systems.
+
+Start or restart HTTPD/Apache2 to pick up the new configuration.
+
+Now we have to configure and start the uwsgi service.
+Copy the `httpd/manila-uwsgi.ini` file to `/etc/manila`. Update the file to
+match your system configuration (i.e. tweak the number of processes and threads)
+
+Install uwsgi.
+
+On RHEL/CentOS::
+
+    sudo yum install uwsgi-plugin-python3
+
+On Fedora::
+
+    sudo dnf install uwsgi-plugin-python3
+
+On SLES/OpenSUSE::
+
+    sudo zypper install uwsgi-python3
+
+On Ubuntu/Debian::
+
+    sudo apt-get install uwsgi-plugin-python3
+
+And start the manila server using uwsgi::
+
+    uwsgi --ini /etc/manila/manila-uwsgi.ini
+
+.. NOTE::
+
+   In the sample configs port 51999 is used, this is a randomly selected number.
+
+.. _community goals for Pike: https://governance.openstack.org/tc/goals/pike/deploy-api-in-wsgi.html#control-plane-api-endpoints-deployment-via-wsgi

doc/source/contributor/index.rst

@@ -37,6 +37,7 @@ Programming HowTos and Tutorials
 
     development.environment
     development-environment-devstack
+    apache-httpd
     unit_tests
     tempest_tests
     addmethod.openstackapi

httpd/manila-uwsgi.ini

@@ -0,0 +1,18 @@
+[uwsgi]
+socket-timeout = 10
+http-auto-chunked = true
+http-chunked-input = true
+http-raw-body = true
+chmod-socket = 666
+lazy-apps = true
+add-header = Connection: close
+buffer-size = 65535
+thunder-lock = true
+plugins = python
+enable-threads = true
+exit-on-reload = true
+die-on-term = true
+master = true
+processes = 4
+http-socket = 127.0.0.1:61999
+wsgi-file = /usr/local/bin/manila-wsgi-api

httpd/uwsgi-manila.conf

@@ -0,0 +1,3 @@
+KeepAlive Off
+SetEnv proxy-sendchunked 1
+ProxyPass "/share" "http://127.0.0.1:51999" retry=0