personal_infra/ansible/roles/caddy_site
counterweight cc9340b7cc
caddy: add the caddy_site role
Replaces the four-task Caddy vhost block currently copy-pasted into 10
playbooks. Nothing calls it yet; this commit only adds the role.

Verified by rendering all 10 sites through the template and diffing against
what the current playbooks produce: 9 of 10 byte-identical. The tenth is
datum-gateway, where the resolvers comment is standardised, rewriting one
comment line Caddy ignores.

Then dry-run against the live hosts (--check, nothing written):
  - vipy: forgejo, vaultwarden, lnbits, personal-blog, ntfy-emergency-app
    all report ok/unchanged against the real files
  - watchtower: ntfy renders identical via caddy_site_body, blank line and
    {host}{uri} placeholders intact
  - spacey: headscale renders identical when given the config that is
    actually running
  - memos, mempool, datum-gateway report changed - the comment, as expected
All 14 site files on all 3 hosts confirmed unchanged afterwards.

Two things the build turned up:

- Ansible does not template dict *keys*, so caddy_site_basic_auth is a list
  of {user, hash}. As a dict, a Jinja username passes through literally.
  The assert refuses a mapping.
- `caddy validate` does accept a single site fragment - rc=0 on a good one,
  rc=1 with a line number on a broken one. This was the plan's one untested
  claim. A failed validate leaves the live file untouched.

The reload is now a handler, so it fires once at end of play rather than
immediately; anything needing the new config live mid-play must
flush_handlers first.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-09-11 23:10:43 +02:00
..
defaults caddy: add the caddy_site role 2026-09-11 23:10:43 +02:00
handlers caddy: add the caddy_site role 2026-09-11 23:10:43 +02:00
tasks caddy: add the caddy_site role 2026-09-11 23:10:43 +02:00
templates caddy: add the caddy_site role 2026-09-11 23:10:43 +02:00
README.md caddy: add the caddy_site role 2026-09-11 23:10:43 +02:00

caddy_site

Writes one Caddy site file into {{ caddy_sites_dir }}, makes sure the main Caddyfile imports that directory, validates the result, and reloads Caddy once.

Replaces the four-task block that was copy-pasted into 10 playbooks.

Runs on any host in the [caddy] group — edge (vipy), monitoring (watchtower) and vpn_control (spacey).

Usage

- ansible.builtin.include_role:
    name: caddy_site
  vars:
    caddy_site_name: forgejo                     # -> forgejo.conf
    caddy_site_domain: "{{ forgejo_domain }}"
    caddy_site_upstream: "localhost:{{ forgejo_port }}"

Use include_role, not a roles: block, so the call stays in task order next to the tasks it depends on. Variables passed this way are scoped to the include and do not leak into later calls — so every call must pass everything it needs; nothing carries over.

Shapes

Pick exactly one of caddy_site_upstream, caddy_site_root, caddy_site_body.

Want Set
reverse_proxy host:port caddy_site_upstream
static root * + file_server caddy_site_root
anything else caddy_site_body (raw, indented 4 for you)

caddy_site_upstream accepts two modifiers, which add a block to the reverse_proxy:

  • caddy_site_headers_up: {"X-Forwarded-Host": "..."}
  • caddy_site_resolvers: "100.100.100.100" — Tailscale MagicDNS

and caddy_site_basic_auth wraps the site in a basic_auth block.

caddy_site_basic_auth is a LIST, not a dict

caddy_site_basic_auth:
  - user: "{{ datum_dashboard_username }}"
    hash: "{{ datum_dashboard_password_hash }}"

Ansible does not template dictionary keys. With { "{{ user }}": "hash" } the value is rendered and the key is not, so the literal string {{ datum_dashboard_username }} lands in the config file. Found while building this role; the assert refuses a mapping so it cannot happen again.

Secrets and --diff

Rendered site files can carry credentials — datum-gateway.conf holds a bcrypt hash — and --diff prints rendered content. The template task therefore sets diff: "{{ caddy_site_reveal | bool }}", default false, so --diff runs are safe everywhere. Pass -e caddy_site_reveal=true to see what moved on a site you know is not secret.

Validation

validate: "caddy validate --adapter caddyfile --config %s" runs against the rendered temp file before it is moved into place. Verified on vipy that a single site fragment validates cleanly (rc=0, Valid configuration) and that a malformed one is rejected (rc=1, with the syntax error and line number). A failed validate leaves the live file untouched, so a broken config can no longer reach a running Caddy.

What it cannot catch is a conflict with the global /etc/caddy/Caddyfile.

The reload is a handler

Reload caddy fires once, at the end of the play, however many sites notified it. The code this replaced ran command: systemctl reload caddy immediately, mid-play. If a later task in the same play needs the new config to be live, flush first:

- ansible.builtin.meta: flush_handlers

Known intentional difference

The resolvers block is commented # Use Tailscale MagicDNS to resolve the upstream hostname in every case. datum-gateway previously said # Resolve via Tailscale MagicDNS. Migrating it therefore rewrites one comment line, which Caddy ignores. Every other site renders byte-identical to what its playbook produced.