nginx, Python 3 pyvenv, uwsgi, Flask, and OS X with MacPorts

Given a working Flask web application called RarToZip (served from the built in HTTP server), this is the configuration I used on my MacBook to get nginx working as a proxy for uWSGI and Flask.

1. Make sure MacPorts is up to date
   
sudo port selfupdate
sudo port upgrade outdated

2. Install nginx
   sudo port install nginx
   nginx will be installed in /opt/local/sbin/nginx and the configuration files will be in /opt/local/etc/nginx
3. Configure /opt/local/etc/nginx/nginx.conf
   
worker_processes 1;
 
events {
   worker_connections 1024;
}
 
http {
   include mime.types.default;
   default_type application/octet-stream;
 
   sendfile on;
 
   keepalive_timeout 65;
 
   server {
     listen 80;
     server_name localhost;
     charset utf-8;
     client_max_body_size 512M;
 
   location / {
     try_files $uri @RarToZip;
   }
 
   location @RarToZip {
     include uwsgi_params.default;
     root /opt/local/www/RarToZip/static;
     index index.html;
     uwsgi_pass unix:/opt/local/www/RarToZip/RarToZip_uwsgi.sock;
   }
 
   error_page 500 502 503 504 /50x.html;
   location = /50x.html {
     root share/nginx/html;
   }
   }
}

4. Create your web app directory (which presumes /opt/local/www exists)
   
sudo chown chris:everyone /opt/local/www
cd /opt/local/www
pyvenv RarToZip
cd RarToZip
source bin/activate

5. Install your dependencies
   
pip install flask
pip install rarfile
export CC=gcc
pip install uwsgi
ln -s /Library/Framework/Python.framework/Version/3.4/bin/uwsgi bin/

   Note that uwsgi installed into /Library/Framework/Python.framework/Version/3.4/bin/uwsgi.
6. Copy your working app from your development directory (mine was in IdeaProjects/RarToZip)
   
cp ~/IdeaProjects/RarToZip/RarToZip.py
mkdir static
cd static
cp -a ~/IdeaProjects/RarToZip/static/* .
cd ..
mkdir templates
cd templates
cp -a ~/IdeaProjects/RarToZip/templates/* .
cd ..

7. Configure uwsgi to run your app (see nginx.conf, above)
   
[uwsgi]
base = /opt/local/www/RarToZip
app = RarToZip
module = %(app)
venv = %(base)
pyhome = %(base)
pythonpath = %(base)
socket = /opt/local/www/RarToZip/%n.sock
chmod-socket = 666
callable = app
logto = /opt/local/www/RarToZip/logs/%n.log

8. Start nginx
   
sudo /opt/local/sbin/nginx

   If all goes well and nginx doesn’t have any errors on startup, you should be able to browse to an error page at http://localhost/.
9. Start uwsgi
   
uwsgi --ini /opt/local/www/RarToZip/RarToZip_uwsgi.ini