MeshGrpcBoundaryTests replaces the MeshClusterClientBoundaryTests deleted in step 1. Three
self-seeded single-member clusters sharing the ActorSystem name, joined ONLY by gRPC, driving
the REAL CentralCommunicationActor -> MeshGrpcCommandDialer -> Kestrel h2c ->
MeshCommandAuthInterceptor -> NodeCommandGrpcService -> NodeCommunicationActor -> EventStream:
1. No_cross_mesh_Akka_association_forms_between_central_and_either_site — the program's own
point, kept as a test rather than a live-gate note: each cluster stays single-member and
none ever holds another's address as a member.
2. One_dispatch_through_central_reaches_a_node_in_every_cluster_mesh — the fan, with each
site holding its OWN per-cluster PSK, so a dial that selected the wrong cluster's key
would be refused at the far side.
3. Falsifiability_control_a_dial_carrying_the_wrong_cluster_key_delivers_nothing — without
it, (2) cannot distinguish "the gRPC boundary carried it" from "something else in the
process did". The same node then accepts the right key, so the silence is the auth gate
and not a dead endpoint.
All three run fully offline — no Docker fixture — and pass.
Comment sweep across every remaining clusterclient|receptionist hit in src/ and tests/:
the program label becomes "mesh gRPC command plane", and every comment that described the
deleted transport as live now describes what actually runs (Dps = pair-local default,
Grpc = cross-mesh). mesh_transport.proto's header/service comments are reworded; no message,
field or enum is touched — the contract is locked. MeshCommActorPathTests is reshaped rather
than retired: the two paths still exist and still matter, but what a mismatch costs is now a
misleading Unavailable from the gRPC ingress rather than a silently dropped receptionist send.
The only surviving mentions of the old names are the ones that must survive: the fail-closed
rules that name "ClusterClient" as a retired value refused at boot, their tests, and this
test class's own account of what it replaces.
The known-cluster gate published only under Mode=Grpc, but the
interceptor it feeds is registered on every admin node and 1B maps
CentralCommandService by LISTENER PORT — neither consults the mode. A
dark-switch rollback to ClusterClient or Dps would therefore have left
that endpoint serving with the gate permanently inactive, silently
restoring both the timing oracle and the pre-auth secret-store/audit
flood, as a side effect of a rollback nobody would connect to
authentication. The gate is central's cluster inventory, not transport
state, so it is now decoupled from the mode entirely:
- SetKnownClusters + InvalidateAll run on EVERY successful contact load
in EVERY mode, and the contact-refresh timer starts in all three.
Under Dps this is a ConfigDb query every ContactRefreshSeconds that
did not run before; central always has a ConfigDb, and one indexed
read a minute is the cheaper half of the trade.
- The GATE set is built from ALL ClusterNode rows. The eligibility
filter moved out of the query's WHERE and into the loop, so the FAN
set is byte-for-byte what it was (enabled && !maintenance) while the
gate widens. This also dissolves the maintenance coupling flagged in
1A.2: a cluster whose nodes are all disabled or in maintenance can
still ack, and refusing it would make maintenance mode an
authentication switch. Central still refuses clusters it has never
heard of.
- HandleContactsLoaded keeps a documented order — targets adopted, gate
published, cache dropped — now pinned by test.
Guards: PreStart mirrors the null-dialer error for a null PSK provider
(silent absence is the worst outcome there — nothing malfunctions, so
nothing is investigated, while the gate never publishes and keys never
rotate); a failed contact load now says out loud that the gate is stale
and, before any load has succeeded, inactive; MeshGrpcCommandDialer
clamps a non-positive DispatchTimeoutSeconds to 10 with a construction
Warning, because the validator for that key is driver-role-scoped and a
pure-admin central reads it unvalidated; the dialer's local PSK refusal
was shortened so its remediation survives the actor's 200-char
truncation of remote-authored status detail; the portless-node warn-once
set is rebuilt each refresh, so a node that regains then loses a port
warns again — the regression is the occurrence worth seeing.
Docs/pins: dialer disposal comment no longer claims one-way; the two
interceptor-test comments claiming Matches has a default implementation
corrected (it deliberately has none); new pins for per-refresh
invalidation, the SetKnownClusters-before-InvalidateAll order, and one
channel per endpoint via a new CachedChannelCount.
The_known_cluster_set_is_not_published_by_the_other_two_modes is
replaced — its premise is obsolete — by three facts: every mode
publishes, gate set is a strict superset of the fan set, and the handler
ordering.
ControlPlane.Tests 230 -> 236, Host.Tests 92, Cluster.Tests 184,
0 warnings.
MeshGrpcCommandDialer places one NodeCommandService.Execute call on one
node: a GrpcChannel cached per endpoint (the GrpcDeploymentArtifactFetcher
shape), the TARGET node's cluster's bearer plus x-otopcua-cluster naming
that cluster, and a per-call deadline linked to the caller's token. A
cluster with no resolvable key is refused locally with Unauthenticated —
there is no arm on which a command leaves central unauthenticated, even
one the far side would have rejected.
CentralCommunicationActor gains the third mode branch. The contact load
now also projects GrpcPort and, from the SAME rows in the SAME pass,
builds the dispatch set — which is what makes 'the gRPC fan reaches
exactly the SendToAll recipient set' structural rather than two queries
that have to keep agreeing. A row with a null GrpcPort is skipped
warn-once (the TelemetryNodeSource precedent). Per-node results are
piped back for LOGGING ONLY: named node, gRPC status, dropped. No retry,
no queue.
Every dial is scheduled on the thread pool rather than called from the
receive. Found by review and pinned red-first: an async method runs
synchronously to its first await, and the dialer's pre-await work is
TryGetPsk, which blocks on the secret store — bounded but seconds, and
repeated after every refresh since the refresh drops the cache. Dialing
inline parked the actor's mailbox, so deployment acks queued behind a
slow node; the regression test tells an ApplyAck while a dial is held
and fails without the hop.
The contact refresh also wires the Phase 1A register: it publishes the
loaded cluster ids as the PSK provider's known-cluster set and drops the
key cache, so a rotated key takes effect within one ContactRefreshSeconds.
Neither happens under Dps or ClusterClient.
Both existing mode branches are behaviourally untouched and every
existing fact passes unmodified. The one edit to shared text: the
Status.Failure warning drops the word 'ClusterClient', since that handler
now serves all three transports.
ControlPlane.Tests 205 -> 230, Host.Tests 92, Cluster.Tests 184, 0 warnings.
Joseph Doherty