Feature request: config validation command line option

[aman207]

Hi,
I'd like to propose an enchancement for blocky. It would be useful to have a command line option to verify a given configuration file is valid without starting blocky. This gives the opportinity for an administrator to resolve issues before restarting the service. Scripts (or Ansible in my case) could also utilize exit codes to make decisions.

For example, this is Caddy's implmentation of this feature:

> caddy validate --config /etc/caddy/Caddyfile --adapter caddyfile
2024/04/28 21:26:13.128 INFO    using provided configuration    {"config_file": "/etc/caddy/Caddyfile", "config_adapter": "caddyfile"}
Valid configuration

And an error looks like:

> caddy validate --config /etc/caddy/Caddyfile --adapter caddyfile
2024/04/28 21:29:13.125 INFO    using provided configuration    {"config_file": "/etc/caddy/Caddyfile", "config_adapter": "caddyfile"}
Error: adapting config using caddyfile: /etc/caddy/Caddyfile:10: unrecognized global option: test-unknown-option

[aman207]

Amazing, thank you!