A module reads its broker credential from MESH_BROKER_FILE — the sealed
{url,fingerprint} the mesh delivered — and connects over amqps pinned to
exactly that certificate. The pin is two-phase (fetch cert, verify, then
trust only it), because Node's checkServerIdentity does not run under
rejectUnauthorized:false, so a naive connect-then-check would already have
sent the password to whoever answered.
A scoped module (assumeExchanges) never declares the exchanges (its account
may not) nor its own queue with a dead-letter (the broker refuses that to a
non-administrator) — the mesh pre-declared the queue, so it passively checks
it, binds and consumes. The RPC reply queue is lazy, and a module that
registered no tools serves none: a pure-events consumer touches only what its
account allows.
Verified end-to-end against a real broker as the scoped account: the audit
logger consumes # and records events, over an account that is not the
broker's own.
Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF
The per-node process that makes a module's tools serve on the mesh:
- broker-amqp.ts: a concrete AMQP implementation of the sdk's Broker
contract (request/reply over a reply queue + correlation id, publish/
subscribe over a topic exchange). Kept here, not in the sdk, so a
broker-client change never rebuilds a module (ADR 0044).
- runtime.ts: bind the broker, import the assigned modules' tool
entrypoints (each registers as it loads), serveTools. The thin wrapper.
- main.ts: the entrypoint, configured by MESH_BROKER_URL + MESH_TOOL_MODULES.
- Dockerfile: the container a node runs it as.
Verified over a REAL broker: the test spins LavinMQ (the mesh's broker),
the runtime serves a registered tool, a separate connection invokes it by
name over AMQP and gets the result, and an unknown tool is refused over
the wire. So 'modules can serve' is now running-on-the-mesh, not just
proven in a mock.
Claude-Session: https://claude.ai/code/session_01LrgweAeERJYBg88c5cKDzF
jschoubben