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

  
  
  
  

   
   
   
   Published: Tuesday, November 13th, 2012 by 
   Alex Fornuto
  
  
  
  
The 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.
  
  
  
  

   
   
   
   
Contents
   
   
   
   
 
    
Prerequisites
 
    
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