caddy-gen

Generate Caddy configuration for docker sites automatically.

Usage

Create a Docker network for all services that are reverse-proxied by Caddy, e.g. gateway here.

Create a caddy-gen.yml from caddy-gen.example.yml.

services:
  caddy-gen:
    image: gera2ld/caddy-gen
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock
      - /caddy/config:/data
    environment:
      - CADDY_GEN_NETWORK=gateway
      - CADDY_GEN_OUTFILE=/data/docker-sites.caddy
      - CADDY_GEN_NOTIFY={"containerId":"caddy","workingDir":"/etc/caddy","command":["caddy","reload"]}

Then include the generated docker-sites.caddy in your Caddyfile.

import path/to/docker-sites.caddy

Given a service with the following compose file:

services:
  my-service:
    # ...
    labels:
      virtual.bind: 80 my-service.example.com

networks:
  default:
    external: true
    name: gateway

Caddy config will be generated automatically to proxy my-service.example.com to my-service:80.

Development

This project is written in Go and uses Docker for containerization.

Building

# Build the Docker image
just build

# Push the Docker image
just push

# Run the Docker container
just run

# Run locally for development
just dev

Environment Variables

• CADDY_GEN_NETWORK: The Docker network to monitor (default: gateway)
• CADDY_GEN_OUTFILE: The output file for Caddy configuration (default: docker-sites.caddy)
• CADDY_GEN_NOTIFY: JSON configuration for notifying Caddy to reload (format: {"containerId":"caddy","workingDir":"/etc/caddy","command":["caddy","reload"]})

Label Format

The virtual.bind label supports the following format:

[PATH] PORT HOSTNAME1 [HOSTNAME2...] [| DIRECTIVE1] [| DIRECTIVE2...]

• PATH: Optional path prefix for the reverse proxy
• PORT: The port to proxy to
• HOSTNAME: One or more hostnames to match
• DIRECTIVE: Optional directives, prefixed with host: for host-level directives or without prefix for proxy-level directives

Multiple bindings can be separated by semicolons (;).