Nginx Beginner’s Guide

Configuration File’s Structure

• nginx modules are controlled by directives defined in /etc/nginx/nginx.conf.
• two types of directives
  • simple directive: name and parameters separated by spaces and ends with ;, e.g., listen 8080;
  • block directive: name and parameters separated by spaces and ends with a body of curly braces ({}) which contains additional instructions and directives, called a context, e.g., events, http, server, location.
  • events and http reside main context, location in server in http, so like below

    events
    http {
      server {
          location 
      }
    }

• # makes command line as comments, e.g., # events

serving static contents

# /etc/nginx/nginx.conf
http {
    server {
        listen 80;
        location / {
            root /data/www
        }
        location /image/ {
            root /data
        }
    }
    server {   
        ...
    }
    server {   
        ...
    }
}

• first, multiple server directives can be defined.
• they are distinguished by ports to which it listen and by server_names.
• once which server takes care of a request, location attempts to match given URI.
• matching URI is appended to the prefix defined in root
  • e.g., a request http://localhost/images/example.png maps to a static file /data/images/example.png on the local machine.
  • e.g., a request http://localhost/some/example.html maps to a static file /data/www/some/example.html on the local machine.
  • nginx returns 404 error if no such file exists in the path.

setting up a proxy server

server {
    listen 8080;
    root /data/up1;

    location / {

    }
}
server {
    listen 80;
    location / {
        proxy_pass http://localhost:8080;
    } 
#   location /image/ {
    location ~ \.(gif|jpg|png)$ {
        root /data;
    }
}

• in the fisrt server, note that root directive is in the context of server instead of location as above.
• when there is no root specified within location, it falls back to it.
• in the second server block, a request is filtered for image files with the extensions of gif, jpb, or png. All the other requests are passed to proxied server.

setting up fastCGI proxying

server {
    location / {
        fastcgi_pass localhost:9000;
        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
        fastcgi_param QUERY_STRING  $query_string;
    }
}

• not much to say about for now..

REFERENCES

Beginner’s Guide (link)