systemd hands a unit's credentials to every process of that unit, and a
host job is a process of the runner daemon, so the `LoadCredential=` on
gitea-runner-swarm still let any workflow read the registration token
from `$CREDENTIALS_DIRECTORY`.
swarm-ci-runner-register.service, a oneshot under the daemon's dynamic
user and state dir, now holds the only `LoadCredential=` and runs the
precond and `act_runner register` (only when `.runner` is missing). The
daemon unit has no credential, no `EnvironmentFile` and no `TOKEN`; its
pre-start step starts the register unit, so a missing token fails the
daemon's start and `Restart=on-failure` retries it.
The precond compares `.runner`'s labels in the form the daemon rewrites
them to (`nix` -> `nix:host`); compared verbatim, a scheme-less label
re-registered the runner on every start.
tmpfiles removes the unused `registration-token.env` and upstream's
`.token-hash`/`.labels` markers.
The runner got its registration token through an `EnvironmentFile`
(`TOKEN=…`), so the daemon carried it for its whole life, and for a
`host` label act_runner copies its environment into every job step:
any workflow could read a token that registers runners on the forge.
The host unit now writes the bare token, and the runner unit loads it
with `LoadCredential=`. The upstream pre-start step, which registered
from `$TOKEN`, is replaced by one register step that reads the token
from `$CREDENTIALS_DIRECTORY` and runs `act_runner register` only when
`.runner` is missing, with the instance URL, name, labels and config
file upstream used. The precond now also removes `.runner` when its
labels differ from the configured ones, which upstream's step covered.
A changed token alone no longer re-registers.
Host jobs can still read `.runner` itself (#4979).
Closes#4974
The CI runner was a hive deploy module: hive-ci.nix ran it beside the
forge, and hive-c0re registered it through the forge's admin API with
the `core` token, writing the registration token through hive-priv. It
could only run on the forge's host, and it kept an admin-scoped forge
token on a hive.
Now the runner is a swarm service:
- swarm-ci-runner.nix runs it in a `swarm-ci-runner` container on the
host that sets deploy.ci-runner.enable, reaching the forge by name.
It needs neither the forge nor a hive there.
- swarm-controller reads the forge's runner registration token with its
own admin token and writes it to swarm/services/ci-runner/
registration-token whenever it differs from what it last wrote. Its
grant on that path is create/update only.
- The runner's own leaf (CN swarm-ci-runner, role and policy of the same
name) reads that one path. swarm-bao-ci-runner.service fetches it into
the runner's EnvironmentFile and restarts the runner on a change.
- A pre-start step removes .runner when the daemon's journal since its
last start holds Forgejo's "unregistered runner" refusal (the daemon
exits 1 when its startup Declare gets it), or when .runner names
another forge address; upstream's pre-start step then registers again.
Removed from the hive side: hive-ci.nix and deploy.forgejo.ci.*,
forge/ci_runner.rs, PrivRequest::RegisterCiRunner and its handler and
ReadWritePaths entry, InfraContainer::Ci with hivectl's --ci and the
dashboard's hive-ci journal entry, HYPERHIVE_FORGE_CI_ENABLED, and
read:admin,write:admin from CORE_TOKEN_SCOPES: nothing else in hive-c0re
calls /api/v1/admin/*. The old ci options, under both swarm.forge.ci and
deploy.forgejo.ci, now fail evaluation naming deploy.ci-runner.
The forge's half of the old ci.enable, the actions/checkout mirror and
DEFAULT_ACTIONS_URL = self, is deploy.forgejo.actionsFromSelf.
Closes#4954