cmd/mesh-controller/modules.go

@@ -584,16 +584,25 @@ func issueOnTheNewBus(ctx context.Context, inv *inventory.Inventory, m catalogue
 // (`rollout mint`, design 28 task 5.2) rather than the one in this process's environment.
 func issueWith(ctx context.Context, inv *inventory.Inventory, m catalogue.Manifest,
 	node, busAddress string, known broker.Broker, reachable, user, password string) error {
+	// The seats this module claims, with the verbs each promises (novox/hq ADR 0159): the runtime
+	// serves a claimed seat's verbs with its tools of the same name, and the bus admits only the
+	// holder's subscription — so the runtime tries each claim and the grant decides. Written here
+	// because this file is the one thing the mesh writes that the runtime reads before it speaks.
+	claims, err := claimsFor(ctx, inv, m)
+	if err != nil {
+		return err
+	}
 	held, err := json.Marshal(struct {
-		URL         string `json:"url"`
-		Fingerprint string `json:"fingerprint,omitempty"`
-		Node        string `json:"node"`
-		Module      string `json:"module"`
-		User        string `json:"user"`
-		Password    string `json:"password"`
+		URL         string       `json:"url"`
+		Fingerprint string       `json:"fingerprint,omitempty"`
+		Node        string       `json:"node"`
+		Module      string       `json:"module"`
+		User        string       `json:"user"`
+		Password    string       `json:"password"`
+		Claims      []seatClaimed `json:"claims,omitempty"`
 	}{
 		URL: "nats://" + reachable, Fingerprint: known.Fingerprint,
-		Node: node, Module: m.Module, User: user, Password: password,
+		Node: node, Module: m.Module, User: user, Password: password, Claims: claims,
 	})
 	if err != nil {
 		return err
@@ -680,3 +689,36 @@ func namesNoInstallation(m catalogue.Manifest) error {
 		"on purpose under %s with its reason, or take it out:\n  - %s",
 		m.Module, catalogue.NamesOnPurpose, strings.Join(named, "\n  - "))
 }
+
+// seatClaimed is one seat a module claims, as its runtime needs it: the name, the scope (a
+// node-scoped seat's verb carries the machine, design 33 §4) and the verbs the seat promises.
+type seatClaimed struct {
+	Seat   string   `json:"seat"`
+	Scope  string   `json:"scope"`
+	Serves []string `json:"serves,omitempty"`
+}
+
+// claimsFor joins a module's claims with the seats' protocols from the mesh's records.
+func claimsFor(ctx context.Context, inv *inventory.Inventory, m catalogue.Manifest) ([]seatClaimed, error) {
+	if len(m.Claims) == 0 {
+		return nil, nil
+	}
+	seats, err := inv.Seats(ctx)
+	if err != nil {
+		return nil, err
+	}
+	byName := map[string]catalogue.Seat{}
+	for _, s := range seats {
+		byName[s.Name] = s
+	}
+	var out []seatClaimed
+	for _, c := range m.Claims {
+		claimed := seatClaimed{Seat: c.Name, Scope: c.At()}
+		if s, known := byName[c.Name]; known {
+			claimed.Scope = s.Scope
+			claimed.Serves = catalogue.VerbNames(s.Serves)
+		}
+		out = append(out, claimed)
+	}
+	return out, nil
+}

internal/broker/invokes_test.go

@@ -91,3 +91,16 @@ func TestADeclaredInvokeReachesTheComposedUser(t *testing.T) {
 	}
 	has(t, perms.Publish, "mesh.mod.*.tool.>")
 }
+
+// A module's tool is addressed two ways (novox/hq ADR 0159): to whichever instance answers, and to
+// the instance on one machine. A grant for the tool covers both and nothing wider.
+func TestInvokingAToolMayAddressTheMachineToo(t *testing.T) {
+	got, err := invokedSubjects([]string{"postgres.postgres_query"})
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := []string{"mesh.mod.postgres.tool.postgres_query", "mesh.mod.postgres.tool.postgres_query.*"}
+	if len(got) != 2 || got[0] != want[0] || got[1] != want[1] {
+		t.Fatalf("the grant is %v, want %v", got, want)
+	}
+}

internal/broker/nats.go

@@ -660,7 +660,10 @@ func invokedSubjects(invokes []string) ([]string, error) {
 			return nil, fmt.Errorf(
 				"%q does not name a tool: one invokes <module>.<tool>, seat:<seat>.<verb>, or * for every one", t)
 		}
-		out = append(out, "mesh.mod."+module+".tool."+tool)
+		// Both ways a module's tool is addressed (novox/hq ADR 0159): to whichever instance
+		// answers, and to the instance on one machine, which is the same subject with the machine
+		// as its last token.
+		out = append(out, "mesh.mod."+module+".tool."+tool, "mesh.mod."+module+".tool."+tool+".*")
 	}
 	return out, nil
 }