Research 031 counted the repairs people made by hand: a push to unstick a
plan waiting on a report, a controller restarted to make an object again, a
plan closed, a consumer re-made from now. Each was the ordinary path taken
again by someone who noticed. The healer registry makes each a registered
response to one condition kind, with a budget, a settle and its event:
- H1 sent-not-reported: ask the machine's node-engine to report again
(mesh.node.<n>.ask.report); if it does not report what it was sent, send
it again, never moving a build a policy or a plan holds back
- H2 stalled: close a plan whose wait is superseded or finished
- H3 holder-silent / consumer-lost: the send's own assertion of the bus's
objects (issue 208's note)
- H4 consumer-behind: consumer-reset, only for a consumer the stream table
marks resettable (the controller's own events consumer)
- H5 is the identity provider's own repair (ADR 0224 §5), registered only
Success is the observation clearing the condition, never the healer; a spent
budget hands the condition to the operator, urgent, with what was tried, and
no healer touches it again. Every act is begun in the store before it is made
(migration 0070), kept in the condition's tried as "healer Hn" and said as
the seat event healer-acted; a heal is never a hand act. More than twelve acts
in an hour stop every healer until an hour after the last, said urgently.
Only the lease holder heals.
S15 is live: a cause repaired by hand twice in a fortnight raises
healer-wanted, naming the healer that was not enough where one exists. D6's
far-behind finding has its own kind, consumer-behind. Nodes are granted the
question; the controller's grant gains healer-acted (genesis lock in
mesh-host). `healers` lists the registry, the acts and the brake; status
counts the week's heals.
Two controllers could both act (issue 204), a reconcile's report could
overtake the apply after it and the digest decided (issue 267), and a grant
could make a second writer of a machine's report.
- The lease (internal/lease, ADR 0229): mesh-controller_lease key `holder`,
15 s age, renewed every 5 s by compare-and-set; the epoch is the revision
it was taken at. The gate is the clock (stops 3 s before expiry); a refused
renewal is a loss and the process exits; a holder that stops gives it back.
serve takes it before asserting the bus. Epochs kept in the store
(migration 0068 controller_epoch) as a floor: a bucket raised from nothing
is compacted past it. Unleased (no epoch, S12 urgent) only when nobody
holds it and the bus will not let it be written. A shell command acts
under the holder's epoch, or its own lease when none.
- Declarations carry `epoch` inside the signed envelope, only to a machine
whose latest account carried a report_sequence (mesh-host #35); would-send
is composed with the epoch last sent. Allot and the send both pass the gate.
- Reports: contract in internal/link/order.go (epoch, sequence,
report_sequence, older_than, refused_older). Accounts kept by epoch, then
sequence, then report sequence; older refused, counted; unordered reports
keep the digest rule. Plans by compare-and-set on a revision, with epoch.
Conditions and calls carry the epoch and are not written off the lease.
- S12 and S13 (naming the writer by epoch) watched, D5 run; reset of the
bucket said. Writers table compiled in and enforced in PermissionsFor; the
controller no longer publishes mesh.control.>. A contract per consumed
kind, and the empty-on-error lint over the repository.
- mesh-host pinned to its main with the epoch in the validator (D1 validates
the envelope as sent).
Needs mesh-host's genesis lock with the lease grant (mesh-host PR) for
TestTheInstallersFirstUserListIsWhatTheControllerWouldCompose.
jochen