Read the seat mesh-placement's state through the sdk's PlacementKeys in mesh-conditions, mesh-config, mesh-provisioner, mesh-vault and mesh-self-check, so they read its keys per module and node and the form before alike while it is delivered (issue 774, research 072 row 37)

modules/mesh-provisioner/cmd/mesh-provisioner/holder.go

@@ -903,9 +903,9 @@ func (h *Holder) put(key string, p provisions.Provision) {
 
 // ---- what a change touches --------------------------------------------------------------------------------------
 
-// NodesOfPlacement is the node a placement key names.
+// NodesOfPlacement is the node a placement key names, in either form (research 072 row 37).
 func NodesOfPlacement(key string) []string {
-	if n, err := delivery.ParsePlacementKey(key); err == nil {
+	if n, _, _, err := delivery.ParsePlacementKey(key); err == nil {
 		return []string{n}
 	}
 	return nil
@@ -938,25 +938,23 @@ func (h *Holder) NodesOfModule(module string) []string {
 	return sortedKeys(nodes)
 }
 
-// placedOn is every node a module is placed on, sorted.
+// placedOn is every node a module is placed on, sorted, from the placement's keys in either form
+// (delivery.PlacementsOf; research 072 row 37). A node whose keys do not read whole is read as they stand.
 func (h *Holder) placedOn(module string) []string {
 	nodes := map[string]bool{}
+	raw := map[string][]byte{}
 	if keys, err := h.Store.Keys(PlacementRead); err == nil {
 		for _, k := range keys {
-			n, err := delivery.ParsePlacementKey(k)
-			if err != nil {
-				continue
+			if e, err := h.Store.Get(PlacementRead, k); err == nil && e != nil {
+				raw[k] = e.Value
 			}
-			e, err := h.Store.Get(PlacementRead, k)
-			if err != nil || e == nil {
-				continue
-			}
-			if p, err := delivery.DecodePlacement(e.Value); err == nil {
-				for _, m := range p.Modules {
-					if m.Module == module {
-						nodes[n] = true
-					}
-				}
+		}
+	}
+	placements, _ := delivery.PlacementsOf(raw)
+	for n, p := range placements {
+		for _, m := range p.Modules {
+			if m.Module == module {
+				nodes[n] = true
 			}
 		}
 	}

modules/mesh-provisioner/cmd/mesh-provisioner/holder_test.go

@@ -191,7 +191,17 @@ func TestAKeysStateFollowsItsProvidersOutcome(t *testing.T) {
 	// A provision's credential is the vault's own provision, on the consumer's node for a login of its own, and the
 	// provision depends on it (clauses 3, 6).
 	c := newMesh()
-	c.s.write(t, PlacementRead, "placement.novox", `{"v":1,"node":"novox","decided":{},"modules":[{"module":"mesh-vault"}]}`)
+	// The placement in its keys per module and node (research 072 row 37).
+	novox, err := delivery.PlacementValues(delivery.Placement{Node: "novox", Modules: []delivery.PlacedModule{{Module: "mesh-vault"}}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	for k, v := range novox {
+		c.s.write(t, PlacementRead, k, string(v))
+		if n := NodesOfPlacement(k); !slices.Equal(n, []string{"novox"}) {
+			t.Errorf("NodesOfPlacement(%q) = %v", k, n)
+		}
+	}
 	pair := pgDB
 	pair.CredentialForm = "pair"
 	c.atWant["g14"] = map[string]catalogue.Plan{"gitea": planOf(pair)}