WSGI using uWSGI and nginx on Ubuntu 12.04 (Precise Pangolin)

Published: Tuesday, November 13th, 2012 by Alex FornutoThe uWSGI server provides a non-FastCGI method for deploying Python applications with the nginx web server. In coordination with nginx, uWSGI offers great stability, flexibility, and performance. However, to deploy applications with uWSGI and nginx, you must compile nginx manually with the included uwsgi module.
ContentsPrerequisites
Installing uWSGI and Configuring Nginx
Configuring uWSGI
Additional Application Servers
More Information

Prerequisites

Before you begin installing and configuring the components described in this guide, please make sure you've followed our instructions for setting your hostname. Issue the following commands to make sure it is set properly:hostname
hostname -f
The first command should show your short hostname, and the second should show yourfully qualified domain name (FQDN).
You should also make sure your system is up to date. Enter the following commands, one by one, and install any available updates:apt-get update
apt-get upgrade

Installing uWSGI and Configuring Nginx

To get started, you'll install uWSGI and other packages, and then configure nginx. Here's how:
Begin by installing uWSGI and nginx from the Ubuntu repository:apt-get install nginx-full uwsgi uwsgi-plugin-python

Create a virtual host file by entering the following command, replacing example.com with your domain name:nano /etc/nginx/sites-available/example.com

Using the virtual host configuration below as a guide, create your configuration file.File:/etc/nginx/sites-available/example.com

server {
listen          80;
server_name     $hostname;
access_log /srv/www/example.com/logs/access.log;
error_log /srv/www/example.com/logs/error.log;

location / {
#uwsgi_pass      127.0.0.1:9001;
uwsgi_pass      unix:///run/uwsgi/app/example.com/example.com.socket;
include         uwsgi_params;
uwsgi_param     UWSGI_SCHEME $scheme;
uwsgi_param     SERVER_SOFTWARE    nginx/$nginx_version;

}

location /static {
root   /srv/www/example.com/public_html/static/;
index  index.html index.htm;

}

}

Link the virtual host file to sites-enabled by entering the following command, replacing example.com with your domain name:ln -s /etc/nginx/sites-available/example.com /etc/nginx/sites-enabled/example.com

Depending on your configuration, you may wish to remove the link to the default virtual host by entering the following command:rm /etc/nginx/sites-enabled/default

Create directories for your website's data by entering the following commands, one by one, replacing example.com with your domain name:mkdir -p /srv/www/example.com/public_html/static
mkdir /srv/www/example.com/application
mkdir /srv/www/example.com/logs

All requests to URLs ending in /static will be served directly from the /srv/www/example.com/public_html/static directory.

Configuring uWSGI

Now we need to configure uWSGI. Here's how:
Create the uWSGI config file by entering the following command, replacing example.com with your domain name:nano /etc/uwsgi/apps-available/example.com.xml

Using the configuration below as a guide, create your configuration file.File:/etc/uwsgi/apps-available/example.com.xml

<uwsgi>
<plugin>python</plugin>
<socket>/run/uwsgi/app/example.com/example.com.socket</socket>
<pythonpath>/srv/www/example.com/application/</pythonpath>
<app mountpoint="/">

<script>wsgi_configuration_module</script>

</app>
<master/>
<processes>4</processes>
<harakiri>60</harakiri>
<reload-mercy>8</reload-mercy>
<cpu-affinity>1</cpu-affinity>
<stats>/tmp/stats.socket</stats>
<max-requests>2000</max-requests>
<limit-as>512</limit-as>
<reload-on-as>256</reload-on-as>
<reload-on-rss>192</reload-on-rss>
<no-orphans/>
<vacuum/>
</uwsgi>

Link the configuration to apps-enabled by entering the following command, replacing example.com with your domain name:ln -s /etc/uwsgi/apps-available/example.com.xml /etc/uwsgi/apps-enabled/example.com.xml

If you want to deploy a "Hello World" application, insert the following code into the /srv/www/example.com/application/wsgi_configuration_module.py file:File:/srv/www/example.com/application/wsgi_configuration_module.py

import os
import sys

sys.path.append('/srv/www/example.com/application')

os.environ['PYTHON_EGG_CACHE'] = '/srv/www/example.com/.python-egg'

def application(environ, start_response):
status = '200 OK'
output = 'Hello World!'

response_headers = [('Content-type', 'text/plain'),
('Content-Length', str(len(output)))]
start_response(status, response_headers)

return [output]

Restart uWSGI with the command:service uwsgi restart

Restart the web server by issuing the following command:service nginx restart

You can test by pointing a web browser to your domian. If you see Hello World!than you have succesfully configured your Linode for uWSGI with Nginx!

Additional Application Servers

If the Python application you've deployed requires more applicationresources than a single Linode instance can provide, all of themethods for deploying a uWSGI application server are easily scaled torely on multiple uSWGI instances that run on additional Linodes withthe request load balanced using nginx's upstreamcapability. See our documentation of proxy and software loadbalancing with nginxfor more information. For a basic example configuration, see thefollowing example:File excerpt:nginx configuration

upstream uwsgicluster {
server 127.0.0.1:9001;
server 192.168.100.101:9001;
server 192.168.100.102:9001;
server 192.168.100.103:9001;
server 192.168.100.104:9001;
}

server {
listen   80;
server_name www.example.com example.com;
access_log /srv/www/example.com/logs/access.log;
error_log /srv/www/example.com/logs/error.log;

location / {
include        uwsgi_params;
uwsgi_pass     uwsgicluster;
}

location /static {
root   /srv/www/example.com/public_html/static/;
index  index.html index.htm;
}
}

In this example, we create the uwsgicluster upstream, which hasfive components. One runs on the local interface, and four runon the local network interface of distinct Linodes (the192.168. addresses or the private "back end" network). Theapplication servers that run on those dedicated application serversare identical to the application servers described above. However, theapplication server process must be configured to bind to theappropriate network interface to be capable of responding to requests.
原文链接：https://library.linode.com/web-servers/nginx/python-uwsgi/ubuntu-12.04-precise-pangolin