vinzenz/hyperhive
vinzenz/hyperhive
Watch
0
0
Fork
You've already forked hyperhive
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 2

swarm-matrix-ctl: one control binary for the matrix container, not one per job

Browse source 
Renames `swarm-matrix-minter` and reshapes it around subcommands. Minting
is now `swarm-matrix-ctl mint`.

Running rust inside `containers.hive-matrix` is not free: it needs its own
store identity, its own cert role and its own bind mounts, and every one of
those is per-*container*, not per-task. A second single-purpose crate would
have had to duplicate that plumbing to add one action, so the next thing
that has to run in there should be a verb here rather than a new crate.
The old name guaranteed the opposite.

`main.rs` is clap dispatch; the minting logic moves to `mint.rs` unchanged.
A bare invocation is refused: `mint` writes a credential, so "no verb"
defaulting to it would make a typo in the unit mint rather than fail.

The environment prefix moves with it, `MATRIX_MINTER_*` → `MATRIX_MINT_*`.
Scoped to the verb and not to the binary, because a binary-scoped prefix is
one the next verb has to share or widen, and a widened one never narrows
again. A test asserts every variable carries the verb's prefix.

The principal renames too. The cert role, bao policy, granting unit, leaf
filename and `certAuthCns` entry all have to spell one string the same way,
so leaving them as `swarm-matrix-minter` would have rebuilt the naming
split this branch exists to remove. Renaming the nix options alongside is
free here: every one of them is introduced by this PR and has never been
released, so no operator config names them yet.

`ExecStart` now names the verb, which is a contract between a nix string
and a clap enum that fails at deploy time with no local signal. Both ends
assert it: `mint_is_spelled_the_way_the_unit_invokes_it` in the crate, and
a new module-eval arm reading the rendered `ExecStart`.

docs/getting-started/setup.md drops the sender token from its "live on the
host" list: setup does not touch this credential, so a setup guide has no
reason to name it.
This commit is contained in:
atlas 2026-09-20 14:29:45 +02:00 • committed by mara
commit 67ba28448f
23 changed files with 319 additions and 172 deletions
Download patch file Download diff file Expand all files Collapse all files

44
swarm-matrix-minter/README.md
View file

@ -1,44 +0,0 @@
# swarm-matrix-minter
A boot-time oneshot that runs **inside `containers.hive-matrix`**, beside the
homeserver, and puts the appservice sender account's access token into the swarm's secret
store under an identity of its own.
## Why it lives in the matrix container
The credential it mints is authorised by the appservice `as_token`, and the
container already holds that: `nix/host-modules/hive-matrix.nix` bind-mounts the
rendered appservice registration into it read-only, because that is how tuwunel
itself is handed the registration. Minting anywhere else would mean copying the
`as_token` to a second holder — and the point of this component is that the hive
stops being one.
It is not the swarm controller for the same reason, plus a structural one: a
homeserver has exactly **one** `@hive:` account and a swarm runs one
homeserver, so "mint it once" needs no lock, no lease and no trigger surface — it
is a property of the thing being minted.
## Idempotency
The **store** is the key, not the homeserver. A run reads
`swarm/services/matrix/sender-token` first and returns without touching the
homeserver when something is already there. Only an empty path reaches the mint
ladder:
1. `POST /_matrix/client/v3/register` with `"type": "m.login.application_service"`
— one round trip, no UIAA.
2. `M_USER_IN_USE` (the expected arm on a homeserver that has already loaded the
registration, since the account is the appservice's own `sender_localpart`) →
`POST /_matrix/client/v3/login` as the appservice, same pinned `device_id`, so
the old device is replaced rather than duplicated.
3. Write the result to the store.
A crash between the homeserver call and the store write is recoverable: the next
run takes arm 2.
## 🩸 A secret is a path, never a value
Nothing here logs, prints or interpolates a token. The mint ladder's errors are
built from the homeserver's _status_ and its `errcode`, never its body, because a
`/login` response body is an access token. The one identifier this binary logs is
the store path it wrote.