hyperhive/swarm-controller
Repository files (latest commit first)
Filename Latest commit message Latest commit date
iris 48aa7a1e79 swarm-controller: let creating an agent reuse a destroyed name
Review caught a path the new declaration node breaks: an operator may
already declare an agent `Destroyed` over the per-agent state endpoint,
and `apply` then refuses any transition off that state. Before the
wanted-state node existed the refusal was inert at creation time, but
now creating an agent under a previously-destroyed name builds its
identity, repo and config, fails the declaration, and silently cancels
the deploy — while the caller sees a 200 and a job id.

`AgentState::Destroyed`'s own doc comment already sanctions this case
("no state that brings a destroyed agent back short of a fresh deploy");
nothing implemented it. Give `apply` an `Intent`, keep the refusal for
redeclares, and add `WantedWriter::create` for the one caller that is a
fresh deploy. A separate method rather than a parameter on `set`, so no
other caller can reach the override by passing an argument wrong.
2026-09-18 22:59:29 +02:00
..
src swarm-controller: let creating an agent reuse a destroyed name 2026-09-18 22:59:29 +02:00
Cargo.toml swarm: mint, publish and login-verify an agent's store identity at create 2026-09-18 15:05:24 +02:00
README.md check-issue-refs: catch full forge issue URLs too, drop internal links from docs entirely 2026-09-09 21:15:28 +02:00

swarm-controller

The swarm-level daemon. Where hive-c0re owns the agents on one host, this owns what is true across hives — so a swarm runs one of them and most hives leave it off.

Opt-in per host via services.hyperhive.deploy.swarm-controller.enable, which is deliberately not derived from services.hyperhive.enable: turning it on is a statement about swarm topology, not about whether hyperhive is installed.

What it does today

Serves one /health endpoint and holds no state.

That is the whole intent of the first slice. The point is to make the unit real — service user, runtime and state directories, socket, nginx reachability — so the swarm-level surfaces that follow have somewhere to land. Inventing those surfaces before they are agreed would bake in a shape nobody chose. See the hyperhive.swarm consolidation epic.

Why a unix socket, not a port

The hive-gateway's nginx is the only intended client and reaches the socket through a bind-mount. A listener that is never bound to an address cannot be reached from off-host by mistake.

The socket path is services.hyperhive.deploy.swarm-controller.socketPath, default /run/swarm-controller/controller.sock, exported to the process as SWARM_CONTROLLER_SOCKET.

⚠️ The socket's directory is its access control

The socket is 0666. It has to be: nginx runs as a different user and connect(2) needs write. This matches how hive-c0re publishes the per-agent sockets, and rests on the same argument — "the bind source dir is per-agent on host so blast radius is unchanged."

What keeps that safe is that the directory holds one socket. So:

Never point socketPath at a directory that carries anything else. /run/hyperhive above all — it holds host.sock, the host admin socket. Pointing nginx at that directory to reach this socket would put the admin socket within its reach too.

nginx is a host service, so nothing narrows what it can reach except the directory itself — that is the whole of the access control. A unit test pins the default path so a tidying edit fails instead of reviewing cleanly.

RuntimeDirectoryPreserve=yes and the daemon's stale-socket unlink on start are a pair: preserving the directory without the unlink means bind fails with EADDRINUSE after a restart.

Packaging

Built by the workspace derivation and extracted as its own package (nix build .#swarm-controller). Deliberately not in nix/packages' daemonBins — that list is the core stack and drives the bundle services.hyperhive.c0re.package points at, so folding this in would put a swarm-scoped service into every hive's closure.