Both branches changed the seat set from the same starting point, so every number
collided and every `mesh-*` name existed twice. The trunk's numbers and names win:
this branch's records became 0129/0130 and its migrations 0037/0038, and the
hardcoded rename map gave way to the trunk's `seat_alias` table — a rename is a
row now (ADR 0122), not a recompile.
Three of my checks were wrong and the merge is what showed it:
A seat with an empty protocol is a marker, not an incomplete declaration. Most
node-scoped seats are markers — which module is this machine's packet filter —
and refusing one refused most of the set, the showcase module included. A
mistyped field name is already refused by the parser, so an empty protocol was
written as one deliberately.
A claim on a seat this manifest does not declare is not the parser's to judge. A
module may hold a seat another module declared; that is the whole reason ADR 0126
has callers name the seat and not its provider. Whether the seat exists is a fact
about the catalogue, so the refusal is at registration, where every declaration
is in view.
And a seat may share a name with the provision it delivers. `git`, the npm
registry and the artifact store still do, because renaming a delivering seat
cascades to every consumer requiring it, with a window where a holder stops
resolving mid-flight. The trunk deferred exactly those three on purpose.
Full suite green against a real NATS and store.
Moving the build outcome onto its role broke the one module that consumes it, and my own
agreement check passed anyway. The catalogue's subscription derived
`mesh.mod.mesh-build-machine.event.built` — a module namespace for a role's event, which no
such module owns — so it started, connected, and its graph stayed empty. The check compared
names, and the names agreed: the build machine does emit `built`. Only the subjects
disagreed, and a subscription that matches nothing is silence.
A consumed name is a module's event unless it names a role, and this package cannot tell by
looking — so whoever resolved the declaration says which, the way it already does for a seat
held or used. A module that watches a role gets the role's event subject and a consumer
filtered on it; watching grants subscribe and nothing else, because hearing what a role
announced is not taking part in it.
The check now compares the two halves that actually have to match — the subject a consumer
subscribes against the subject an emitter publishes — with a case pinning that it catches
this exact confusion. Comparing names was checking the easy half.
**And that answered the open question about catch-up: there is nothing to build.** The
mechanism exists because a queue on the old bus receives only what is published after it is
bound, so everything built before the catalogue existed was announced to nobody. A stream is
a log and a consumer is a position in it: a consumer created afterwards starts at the
beginning, so the builds are simply there. Asked of a real server, since the whole decision
rested on it — three builds published with nothing listening, then a consumer created, and
all three waiting for it.
Design 25 §7's first item, which existed as a permission model and as nothing a person
could actually be given. There is a record now, and three commands.
Their authority is a list of tools and nothing else. Not a module: they hold no seat,
nothing is addressed to them, nothing is delivered to them, and they have no consumer to
acknowledge. What they have is permission to ask — which is why there is no scope and no
node in the record.
Stating what somebody may call replaces what was there rather than adding to it: a list
that could only grow is a permission nobody can take back. Forgetting somebody takes
their credential with them, because a person's row gone with their bus user left behind
is a credential that still works and that nothing derives — the worst of both, since it
keeps working and nobody can explain why.
The credential is printed once and the mesh keeps only a hash, the same contract a token
has. And it starts working at the next composition rather than immediately, because the
bus's users are a file — said out loud in both the issue and the revoke messages, since
"revoked" that still works for another minute is worth knowing about.
Four properties held by test, each a way of being wrong that would not announce itself:
a person may publish exactly the tool subjects they were given and nothing on control,
nodes or events; they cannot answer a request; changing the list removes what is no longer
named; and forgetting them revokes them.
ADR 0121, first half. The `mesh-*` seats said who does a job and nothing about what
may be said to them or by them, so the mesh had roles it could not describe. They
take the same three fields a module's seat has now, and the machinery that already
derives a work queue, a holder's worker and a permission set from a declared seat
does it for these too.
The build-machine role accepts a build and emits an outcome, so `mesh.build.request`,
`mesh.control.built` and the BUILDS stream are gone. A work queue shared by several
build machines is what a seat's `accepts` already is, and keeping a second mechanism
for it was two places a permission could be wrong.
The controller's own side of a seat is a named list rather than something derived: it
is not a module and declares no `uses`, so which roles the mesh itself submits work to
has to be stated — and stating it makes that question answerable.
Two things this caught:
**The followed event subjects were hard-coded and had just gone stale.** They were
written out while the catalogue still spelled its events as the old bus's routing keys,
so converting those (issue 127) turned the pair into a controller listening to a
subject nothing publishes — the same fault as the issue, from the other side. They
derive from the emitter and the event name now, through the same function the
permission uses, so the two cannot drift apart.
**A role's queue exists before its holder**, checked against a real server, and
asserting twice changes nothing. Work queues until somebody arrives to do it, so
assigning a build machine later flushes the backlog instead of having lost it.
Issue 127 stood because nothing compared the two halves. Every manifest was
well-formed on its own and every derivation correct on its own, and no
cross-module subscription in the mesh matched anything — a subscription that
matches nothing is not an error, it is silence.
Two checks, because the mistake is possible at two scales.
Per manifest: an event is a local name, and `module.` is refused with the name to
write instead. A module emitting under what reads as another module's name is
refused too, pointing at the seat, where a name outlives whoever holds it.
Across the catalogue: where a consumed event's emitter is present, it must emit
that event. It cannot demand a live emitter for everything — a module lives in its
own repository and may be installed long before the one whose events it wants — so
the rule is narrower and still catches this. It found two real dangling
subscriptions the moment it ran.
Wildcards were undecided and two manifests needed them: `*` is one name and `**`
is the rest, spelled the mesh's way and derived to `>` here and `#` on the old bus.
A manifest naming either would stop being true when the wire changed, which is the
whole reason names are local.
And the field documentation taught the old form, examples included — which is why
the drift was uniform across 37 manifests rather than scattered. Nobody was
guessing; everybody followed the comment.
The derivation had nothing feeding it. `BusRecords` reads what it needs — the
machines, what each runs, every manifest, and which machines hold a live token —
and turns it into the records the composer derives from.
**A module's authority comes from its manifest, not from its assignment.** The
assignment says where it runs; what it may say is what it declared. So the two are
read together and the manifest decides, which is also why a seat's protocol is
gathered across the whole catalogue rather than from one manifest: a seat is
declared by one module and held by another, and that is the whole reason a seat
exists.
Three things checked against a real store, each a user that would be wrong in a
way nothing reports:
- A module assigned to a machine becomes a user with exactly the authority it
declared, including the protocol of a seat some *other* module declared — a
module granted nothing on a seat it was assigned to send to would fail on its
first publish with an authorisation error that says nothing about a seat.
- Only a machine holding a live token gets an enrolment user. One outliving its
token is a right to join that nobody issued.
- A module assigned and absent from the catalogue is refused rather than composed
with an empty permission list. The catalogue already refuses to forget an
assigned module, so this is the second line — and it earns its place there,
because relying on another package's invariant is how a rule ends up enforced by
nothing.
People are left empty rather than guessed at: the account model is built and
`operator issue` is not, so there is nobody to derive yet.
jschoubben