Files
mesh-sdk/go/buscompose/health_grants.go
T
jschoubben abf5eace77
mesh/delivery merged: source.main moved to novox/mesh-sdk@036266daff85
mesh/delivery-group group feat/1126-removal merged: every member is merged
mesh/check pass abf5eace7791 on 4a4fac090e9e | unit 6915 run, 1941 kept, 59 skipped | integration 6945 run, 2096 kept, 65 skipped | over bound: unit, …
Let the bus tools remove mesh-catalog's and the engines' leftover consumers on EVENTS
novox_mesh-catalog follows the ended controller's built-before and each <node>_mesh-host restic's backed-up; no part
composes either and nothing reads them (novox_mesh-catalog 10036 behind, each mesh-host 331 never delivered), so the
removal after the delivery takes them with the controller's (issue 1126).

Claude-Session: https://claude.ai/code/session_01NcbgfJ9Gum47zkFKWRaovL
2026-11-02 12:25:56 +01:00

213 lines
11 KiB
Go

package buscompose
import (
"fmt"
"slices"
"sort"
"strings"
"git.novox.be/novox/mesh-sdk/go/catalogue"
"git.novox.be/novox/mesh-sdk/go/health"
)
// **The health holders' grants** (novox/hq ADR 0564 clauses 2, 5 and 8, Limits 2, 4 and 8; issue 1952 S5; ADR 0590).
//
// - Nobody reads mesh-healers' `would` (clause 8): what the healers would have done reaches no condition. Every
// observer's `findings`, the healers' `attempts`, the wants and the haves are read through `reads` as any announced
// state is; and no module writes another's state, so an observer can never write the keeper's buckets (clause 2).
// - The watchman makes its own consumer on DEAD_LETTER_NOTICES, by its own name, pulled, and reads whether the ended
// controller's consumer `controller` still stands; it may neither delete nor change that consumer (clause 5).
// - The bus module's tools run on an account of their own, declared by their bundle's `bus` with `removes`
// (catalogue.BusAccounts), which may remove only keys of the node-engine's acts bucket (Limits 4) and the ended
// controller's leftovers (ADR 0590 clause 6), never the backup's account `broker`, which only reads (ADR 0235).
// HealersWould is what mesh-healers would have done while a controller was placed: read by nobody (ADR 0564 clause 8).
var HealersWould = health.HealersModule + "." + health.WouldState
// ControllerLeftoverConsumers are the ended controller's durable consumers left on the bus, one leftover of the module
// mesh-delivery placed nowhere (issue 1126, milestone section 3), and mesh-catalog's of the controller's built-before,
// which its manifest no longer consumes and no part composes; each `<stream>.<consumer>`.
var ControllerLeftoverConsumers = []string{
"EVENTS." + ControllerName, "EVENTS." + MergesConsumerName, "EVENTS.novox_mesh-delivery", "EVENTS.novox_mesh-catalog",
"CONTROL." + ControllerName, DeadLetterNoticesStream + "." + ControllerName,
}
// ControllerLeftoverConsumersOn are ControllerLeftoverConsumers and, for each node given, the consumer the controller
// made for the node's engine (`EVENTS.<node>_mesh-host`, of restic's backed-up): the engine hears that event without a
// durable consumer, and the grants part composes none for it, so nothing reads it (issue 1126).
func ControllerLeftoverConsumersOn(nodes []string) []string {
out := slices.Clone(ControllerLeftoverConsumers)
for _, n := range nodes {
if safeSubject.MatchString(n) {
out = append(out, "EVENTS."+n+"_"+EngineModule)
}
}
return out
}
// ControllerLeftoverBuckets are the ended controller's buckets, each by its local name (`KV_mesh-controller_<name>`).
var ControllerLeftoverBuckets = []string{"asked", "assignments", "builds", "calls", "checks-running", "composed",
"condition-history", "conditions", "declared-config", "declared-packages", "delivery-merges", "grants", "hand-acts",
"lease", "predefined", "rollouts", "states-announced"}
// ControllerLeftoverStreams are the ended controller's streams, by their names: CONTROL, ASSIGNMENTS, each of its buckets'
// and, for each node given, the declaration files' object bucket the controller wrote (ADR 0486 §2).
func ControllerLeftoverStreams(nodes []string) []string {
out := []string{"CONTROL", AssignmentsStream}
for _, b := range ControllerLeftoverBuckets {
out = append(out, "KV_"+BucketName(catalogue.EndedControllerName, b))
}
for _, n := range nodes {
if safeSubject.MatchString(n) {
out = append(out, "OBJ_"+DeclarationFilesBucket+n)
}
}
return out
}
// BusRemovalGrants are the whole authority of an account whose bus declares removals (ADR 0564 Limits 4, ADR 0590 clause
// 6), each removal its grant: the node-engine's acts bucket read (STREAM.INFO with a subject filter lists what a removal
// would take, so the tools read before they remove) and its keys removed, which nothing else may empty when it fills; and
// the ended controller's leftovers, each consumer and each stream read and deleted by its name, for the nodes given (the
// declaration files' object buckets). A removal outside the set is refused, as the indexer's judge refuses it in a
// manifest (novox/hq ADR 0578 §1).
func BusRemovalGrants(removes, nodes []string) ([]string, error) {
var out []string
for _, r := range removes {
switch r {
case catalogue.RemovesEngineActs:
out = append(out, "$JS.API.STREAM.INFO.KV_"+EngineActsBucket, "$KV."+EngineActsBucket+".>")
case catalogue.RemovesControllerLeftovers:
for _, c := range ControllerLeftoverConsumersOn(nodes) {
out = append(out, "$JS.API.CONSUMER.INFO."+c, "$JS.API.CONSUMER.DELETE."+c)
}
for _, s := range ControllerLeftoverStreams(nodes) {
out = append(out, "$JS.API.STREAM.INFO."+s, "$JS.API.STREAM.DELETE."+s)
}
default:
return nil, fmt.Errorf("a bus account removes %q, which is not one of %s (novox/hq ADR 0564 Limits 4, ADR 0590)", r,
strings.Join([]string{catalogue.RemovesEngineActs, catalogue.RemovesControllerLeftovers}, ", "))
}
}
return out, nil
}
// removesLeftover is an account declared to remove the ended controller's leftovers deleting one of its streams: the
// writers table's one exemption from stream definitions being the grants part's (ADR 0590 clause 6).
func removesLeftover(p Principal, pattern string) bool {
name, ok := strings.CutPrefix(pattern, "$JS.API.STREAM.DELETE.")
return ok && p.Kind == KindProcess && slices.Contains(p.Removes, catalogue.RemovesControllerLeftovers) &&
slices.Contains(ControllerLeftoverStreams(p.FilesFor), name)
}
// removesEngineActs is an account declared to remove keys of the node-engine's acts bucket: the writers table's one
// exemption from a node's engine being the only writer of its keys, for removal (ADR 0564 Limits 4).
func removesEngineActs(p Principal, pattern string) bool {
return p.Kind == KindProcess && slices.Contains(p.Removes, catalogue.RemovesEngineActs) && pattern == "$KV."+EngineActsBucket+".>"
}
// WatchmanDeadLetterConsumer is the watchman's own consumer on DEAD_LETTER_NOTICES, made only once the lease names no
// controller and `controller` is gone (ADR 0564 clause 5).
const WatchmanDeadLetterConsumer = WatchmanModule
// WatchmanDeadLetterGrants are what the watchman may publish for the dead letters in L4 (ADR 0564 clause 5), at least
// privilege: its own pulled consumer on DEAD_LETTER_NOTICES (made, read, pulled, acknowledged); whether `controller`
// still stands (read only); a read of DEAD_LETTERS (its information and one kept message); a copy kept
// (`mesh.events.dead.>`); and on each stream a notice can name (sources: EVENTS, the seats' work queues and the
// modules' own), its information, for a source's age (ADR 0376), and the message given up on, each stream by its name.
// Never a wildcard over the streams and never a bucket's or an object store's stream: a read of any message would read
// every bucket (the lead, 2026-10-29, on issue 1952 S5). Delivering again and dropping stay refused in L4, so it may
// neither delete a message nor publish `mesh.again.>`.
func WatchmanDeadLetterGrants(sources []string) []string {
own := DeadLetterNoticesStream + "." + WatchmanDeadLetterConsumer
out := []string{
"$JS.API.STREAM.INFO." + DeadLetterNoticesStream,
"$JS.API.CONSUMER.INFO." + DeadLetterNoticesStream + "." + ControllerName,
"$JS.API.CONSUMER.CREATE." + own,
"$JS.API.CONSUMER.INFO." + own,
"$JS.API.CONSUMER.MSG.NEXT." + own,
"$JS.ACK." + own + ".>",
"$JS.API.STREAM.INFO." + DeadLettersStream,
"$JS.API.STREAM.MSG.GET." + DeadLettersStream,
deadLetterPrefix + ">",
// And the provisioner clients' reports, the newest per subject read at its start (S21, ADR 0362 §3).
"$JS.API.STREAM.INFO." + ProvAppliedStream,
"$JS.API.STREAM.MSG.GET." + ProvAppliedStream,
"$JS.API.DIRECT.GET." + ProvAppliedStream + ".>",
}
for _, s := range DeadLetterSources(sources) {
out = append(out, "$JS.API.STREAM.INFO."+s, "$JS.API.STREAM.MSG.GET."+s)
}
return out
}
// WatchmanHears are the core subjects the watchman subscribes, with no durable consumer (ADR 0564 clauses 4, 5 and
// Limits 3, 11): the power seat's words (S1, ADR 0211), the providers' failing and recovered words (S8), each tool
// runner's beat (S11), the self-check's checked (S10), a consumer deleted and the bus module's slow consumers and closed
// connections (S9), the provisioner clients' reports (S21), the dead letters kept, and the lease write's events. Never the bus's API audit
// (`$JS.EVENT.ADVISORY.API`): it carries every API call's request and answer in the account, the vault's hashes among
// them (the lead, 2026-10-29).
func WatchmanHears() []string {
return []string{
"mesh.mod.power.event.*",
"mesh.mod.*.event.provisioner.failing",
"mesh.mod.*.event.provisioner.recovered",
"mesh.control.*.tools-alive",
"mesh.seat.mesh-self-check.event." + health.EventChecked,
"$JS.EVENT.ADVISORY.CONSUMER.DELETED.>",
"mesh.mod.nats.event.bus.slow-consumer",
"mesh.mod.nats.event.bus.connection-closed",
ProvAppliedSubjects,
deadLetterPrefix + ">",
}
}
// DeadLetterSources are the streams of names a dead letter may come from, sorted, none twice: each a plain name, never a
// bucket's (KV_) or an object store's (OBJ_) stream, the dead letters' own two streams, or a pattern.
func DeadLetterSources(names []string) []string {
seen := map[string]bool{}
var out []string
for _, n := range names {
switch {
case seen[n], !safeSubject.MatchString(n), strings.HasPrefix(n, "KV_"), strings.HasPrefix(n, "OBJ_"),
n == DeadLettersStream, n == DeadLetterNoticesStream:
continue
}
seen[n] = true
out = append(out, n)
}
sort.Strings(out)
return out
}
// deadLetterSourcesOf are the streams the records' consumers give up on: EVENTS, the work queue of every seat that
// accepts work, and every module's and process's own work queue.
func deadLetterSourcesOf(r Records) []string {
out := []string{EventsStream}
for _, mods := range r.Assigned {
for _, d := range mods {
for _, s := range append(append([]Seat(nil), d.Holds...), d.Uses...) {
if len(s.Accepts) > 0 {
out = append(out, seatStreamName(s.Name))
}
}
for _, q := range d.Queues {
out = append(out, q.Stream)
}
for _, pr := range d.Processes {
for _, q := range pr.Queues {
out = append(out, q.Stream)
}
}
}
}
return DeadLetterSources(out)
}
// keepsDeadLetters is the watchman keeping the dead letters: a second writer of the copies beside the controller, which
// keeps them until its lease is handed away and the watchman after (ADR 0564 clause 5). Delivering again stays the
// controller's in L4.
func keepsDeadLetters(p Principal, pattern string) bool {
return p.Kind == KindModule && p.Module == WatchmanModule && pattern == deadLetterPrefix+">"
}