nginx-study-notes

1 what is nginx?
  At the very core, nginx is an HTTP router. It gives developers the flexibility to build and deploy web apps easier.
2 install with modules(and third-party modules) 
  --> install from source code
    $ sudo apt install build-essential
    $ sudo apt install libpcre3-dev zlib1g-dev libssl-dev
    $ ./configure --prefix=/usr -conf-path=/etc/nginx \
                  --with-http_ssl_module \
                  --with-http_spdy_module \
                  --with-http_realip_module \
                  --with-http_stub_status_module
    $ make && sudo make install    
  --> check installation status: nginx -V
3 basic configuration
  --> the nginx.conf file
  --> the most basic nginx configuration in nginx.conf
    events {}
    http {
      server {}
    }
  --> start nginx server: 
    (1) $ systemctl start nginx // when nginx is installed from package manager
    (2) $ nginx // when nginx is built from source
  --> check nginx running status:
    (1) $ systemctl status nginx // when nginx is installed from package manater
  --> send signal to nginx 
    $ nginx -s stop|quit|reopen|reload
4 configuration details
  4.1 directives
    (1) simple directivee(a config name, with multiple key-value pairs as parameters, and semicolon at the end, e.g., listen 80;)
    (2) context directives
      --> starts with a config name too, but instead of ending with a semicolon, it wraps a group of directives inside a curly braces
      --> e.g., events, http, and server configs
    (3) there is an implied main context wrapping the configuration file, and directives are always inherited downwards