Merge pull request 'A trusted setting is proposed through the settings verb and set only on the operator's warrant (hq ADR 0277)' (#199) from feat/0277-settings-propose into main

cmd/mesh-controller/asker.go

@@ -114,8 +114,14 @@ type asked struct {
 	// Rehearsal is an ask started at the controller's terminal (rehearse.go): about no condition, its answers
 	// perform nothing, and the reconciling of conditions leaves it alone.
 	Rehearsal bool `json:"rehearsal,omitempty"`
+	// Proposal is a settings layer proposed through a verb (proposals.go, novox/hq ADR 0277): about no
+	// condition, set on Approve by the serving controller itself, and left alone by the reconciling of conditions.
+	Proposal *settingsProposal `json:"proposal,omitempty"`
 }
 
+// ofACondition says an ask is one of a condition's: not a rehearsal, not a proposal.
+func (r asked) ofACondition() bool { return !r.Rehearsal && r.Proposal == nil }
+
 // partKey is an ask's place among what is asked: its condition and its part.
 func partKey(condition, part string) string { return condition + "#" + part }
 
@@ -184,6 +190,8 @@ type asker struct {
 	publish func(ctx context.Context, subject string, body []byte, id string) error
 	// call performs an action's verb with its arguments, as the controller.
 	call func(ctx context.Context, a conditions.Action, args map[string]string) error
+	// setLayer sets a proposed settings layer on the operator's warrant (novox/hq ADR 0277); nil cannot.
+	setLayer setOnWarrant
 	// record writes the hand-act log.
 	record func(ctx context.Context, act link.HandAct) error
 	// routerRecord reads the router's record of an ask for a warrant missed; nil reads nothing.
@@ -324,17 +332,45 @@ func (a *asker) reconcile(ctx context.Context) error {
 		return err
 	}
 	byCondition := map[string]asked{} // by partKey
+	// What is open and not a condition's — a rehearsal, a proposal — still counts toward what the router holds
+	// open for the controller (askMostOpen); expired unanswered, it is kept so, as the router says it too.
+	otherOpen := 0
 	for _, r := range all {
-		if r.State == askOpen && !r.Rehearsal {
+		if r.State == askOpen && !r.ofACondition() && !now.Before(r.Ask.Expires) {
+			if _, err := a.store.Change(ctx, r.ID, func(x *asked) bool {
+				if x.State != askOpen || x.Acted != "" {
+					return false
+				}
+				x.State, x.Ended, x.Acted = string(asks.OutcomeExpired), now, "nothing: the ask expired unanswered"
+				return true
+			}); err != nil {
+				return err
+			}
+			continue
+		}
+		if r.State == askOpen && !r.ofACondition() {
+			otherOpen++
+		}
+		if r.State == askOpen && r.ofACondition() {
 			k := partKey(r.Condition, r.Part)
 			if prior, held := byCondition[k]; !held || r.Opened.After(prior.Opened) {
 				byCondition[k] = r
 			}
 		}
 	}
-	// A warrant missed while away, read from the router's record.
+	// A warrant missed while away, read from the router's record: for a condition's ask, and for a proposal's or a
+	// rehearsal's alike.
 	if a.routerRecord != nil {
+		var lookedUp []asked
 		for _, r := range byCondition {
+			lookedUp = append(lookedUp, r)
+		}
+		for _, r := range all {
+			if r.State == askOpen && !r.ofACondition() {
+				lookedUp = append(lookedUp, r)
+			}
+		}
+		for _, r := range lookedUp {
 			if now.Sub(r.Opened) < askCatchUpAfter {
 				continue
 			}
@@ -350,7 +386,7 @@ func (a *asker) reconcile(ctx context.Context) error {
 		}
 		byCondition = map[string]asked{}
 		for _, r := range all {
-			if r.State == askOpen && !r.Rehearsal {
+			if r.State == askOpen && r.ofACondition() {
 				byCondition[partKey(r.Condition, r.Part)] = r
 			}
 		}
@@ -409,7 +445,7 @@ func (a *asker) reconcile(ctx context.Context) error {
 		}
 		return open[i].Key < open[j].Key
 	})
-	openNow := 0
+	openNow := otherOpen
 	for _, c := range open {
 		if !wants(c, now) {
 			continue
@@ -773,7 +809,7 @@ func (a *asker) Decided(ctx context.Context, body []byte) error {
 	if err != nil {
 		return err
 	}
-	stillOpen := r.Rehearsal // a rehearsal is about no condition
+	stillOpen := r.Rehearsal || r.Proposal != nil // a rehearsal and a proposal are about no condition
 	for _, c := range open {
 		stillOpen = stillOpen || c.Key == r.Condition
 	}
@@ -820,15 +856,23 @@ func (a *asker) Decided(ctx context.Context, body []byte) error {
 		args["why"] = why
 	}
 	var acted error
+	outcome := "done"
 	switch {
 	case r.Rehearsal && act.Verb == rehearsalVerb:
 		// A rehearsal's answer performs nothing: it is recorded below as the operator's decision.
+	case r.Proposal != nil && act.Verb == proposalVerb:
+		// A proposed settings layer, set by this controller itself on Approve (novox/hq ADR 0277): the act's
+		// digest of the values is held to the record's own values before anything is set.
+		outcome, acted = a.decideProposal(ctx, *r, act, w)
+		if acted == nil && outcome != "" && !strings.HasPrefix(outcome, "nothing") {
+			outcome = "done: " + outcome
+		}
 	case act.Arguments["silence"] != "":
 		acted = a.silence(ctx, act.Arguments["silence"], conditions.MaxSilence, byWords(w), why)
 	default:
 		acted = a.call(ctx, act, args)
 	}
-	ended, outcome := a.now(), "done"
+	ended := a.now()
 	if acted != nil {
 		outcome = "failed: " + acted.Error()
 	}