Derive the guard from taken modules only: their published private-network ports and their manifests' guards (hq ADR 0103)

cmd/mesh-controller/plan.go

@@ -539,11 +539,24 @@ func renderingFor(ctx context.Context, open *stores, node string,
 	if err != nil {
 		return catalogue.Rendering{}, inventory.Node{}, err
 	}
+	// And, on an adopted node, which modules were taken there: the guard is derived from those
+	// only (novox/hq ADR 0103).
+	var taken map[string]bool
+	if record.Adopted {
+		list, err := inv.Taken(ctx, node)
+		if err != nil {
+			return catalogue.Rendering{}, inventory.Node{}, err
+		}
+		taken = map[string]bool{}
+		for _, m := range list {
+			taken[m] = true
+		}
+	}
 	return catalogue.Rendering{
 		Settings: settings, Generators: gens, Grants: grants, Needed: needed, Ports: ports,
 		Certificate: certificate, Authority: authority, Mesh: private, Names: names,
 		Suffix: overlay.Suffix(), Foundation: foundation, Kept: kept, Adopted: record.Adopted,
-		Given: given,
+		Given: given, Taken: taken,
 	}, record, nil
 }
 

cmd/mesh-controller/sendable_test.go

@@ -225,3 +225,38 @@ func TestConsumersAreToldTheGivenPort(t *testing.T) {
 		t.Fatalf("a port given for the whole mesh was not refused: %v", err)
 	}
 }
+
+// novox/hq ADR 0103: the guard an adopted node is sent follows what was taken there. A store
+// assigned but not taken is not guarded — its port may still be the predecessor's — and taking it
+// guards it from the next declaration.
+func TestTheGuardIsSentForTakenModulesOnly(t *testing.T) {
+	open := aMesh(t)
+	ctx := t.Context()
+	register(t, open, catalogue.Manifest{Module: "store", Version: "1",
+		Listens: []catalogue.Listening{{Port: 5432, From: catalogue.FromMesh}},
+		Guards:  []int{5432},
+		Resources: []map[string]any{{"id": "server", "type": "container", "name": "mesh-store",
+			"ports": []any{"5432:5432"},
+			"image": "registry.example/pg@sha256:" + strings.Repeat("b", 64)}}})
+	if err := open.inventory.SetAdopted(ctx, "anchor", true); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := assign(ctx, open, "anchor", "store"); err != nil {
+		t.Fatal(err)
+	}
+	if hasID(composed(t, open, "anchor").Resources, catalogue.GuardID()) {
+		t.Fatal("an untaken store is guarded")
+	}
+	if err := open.inventory.Take(ctx, "anchor", "store"); err != nil {
+		t.Fatal(err)
+	}
+	for _, r := range composed(t, open, "anchor").Resources {
+		if r["id"] == catalogue.GuardID() {
+			if r["content"] != catalogue.AsGuard([]int{5432}) {
+				t.Fatalf("the taken store's guard is:\n%s", r["content"])
+			}
+			return
+		}
+	}
+	t.Fatal("a taken store is not guarded")
+}