Caddyfile

Caddyfile is the configuration file format used by the Caddy web server. It provides a human-friendly way to define site blocks, server behavior, and options. Caddy can read a Caddyfile directly or convert it to JSON for production deployments.

The basic structure consists of blocks. A site block starts with a label, usually a hostname such as example.com or an address like :80 or :443, followed by curly-braced directives that configure that site. Inside a block, directives are written on separate lines and may take arguments. A global or top-level block, written as a bare set of braces {}, holds options that apply to the whole server. Comments begin with #.

Common directives configure core capabilities. root sets the document root, file_server enables static file serving, and reverse_proxy forwards requests to another service. tls configures certificates and enables automatic TLS via ACME by default. log defines access logging, while redir and rewrite handle URL redirection and rewriting. header edits response headers, and respond can generate inline responses. The encode directive enables compression or streaming features. Many directives are implemented as plugins and can extend functionality.

Example:

example.com {

root * /var/www/html

file_server

log {

output file /var/log/caddy/access.log

}

reverse_proxy localhost:8080

}

Usage notes: the Caddyfile is named Caddyfile by convention and located in the server’s working directory or a specified path. It supports imports and plugins to extend capabilities. Caddy can also run with a JSON configuration, with the Caddyfile serving as a convenient, readable alternative.