mesh-grants: the node-engine's manifest is placed on every node, so its declared state is asserted and created as a placed module's, and it adds no account (issue 774, ADR 0563 §2, §3)

modules/mesh-grants/grants_test.go

@@ -1783,6 +1783,31 @@ func TestGrants(t *testing.T) {
 		}
 	})
 
+	// 774 (ADR 0563 §2, §3): the node-engine's manifest (mesh-host) is placed on every node though no node is assigned it,
+	// so its declared state acts is created as a placed module's, and composed for the user list's create right.
+	t.Run("assertions: the node-engine's declared state is created though no node is assigned it", func(t *testing.T) {
+		b := fixture()
+		b.manifestOf(buscompose.EngineModule, `{"module":"mesh-host","version":"1","state":[{"name":"acts"}]}`)
+		b.loaded = shadowOf(t, b)
+		p := partOn(b)
+		p.Create = b
+		p.Compose()
+		if !slices.Contains(b.creates, "KV_"+buscompose.EngineActsBucket) {
+			t.Fatalf("the node-engine's acts were not created: %v", b.creates)
+		}
+		recs, _ := grants.Records(grants.ReadInputs(b, &grants.Manifests{}))
+		if recs.Engine == nil || len(recs.Engine.State) != 1 || recs.Engine.State[0].Bucket() != buscompose.EngineActsBucket {
+			t.Fatalf("the records carry the node-engine as %+v", recs.Engine)
+		}
+		for node, mods := range recs.Assigned {
+			for _, d := range mods {
+				if d.Module == buscompose.EngineModule {
+					t.Errorf("the node-engine is a module of %s, which would give it a module's account", node)
+				}
+			}
+		}
+	})
+
 	t.Run("assertions: a refused create is said, never stops it, and is tried at the next event", func(t *testing.T) {
 		b := fixture()
 		b.loaded = shadowOf(t, b)

modules/mesh-grants/internal/grants/part.go

@@ -13,6 +13,7 @@ import (
 	"time"
 
 	"git.novox.be/novox/mesh-sdk/go/asks"
+	"git.novox.be/novox/mesh-sdk/go/buscompose"
 	"git.novox.be/novox/mesh-sdk/go/delivery"
 	"git.novox.be/novox/mesh-sdk/go/membership"
 )
@@ -364,6 +365,11 @@ func (p *Part) Last() Result {
 }
 
 func assigned(in Inputs, module string) bool {
+	// The node-engine runs on every node though no node is assigned it (novox/hq ADR 0563 §2, §3): its manifest is
+	// placed everywhere, so its declared state is asserted and created as a placed module's.
+	if module == buscompose.EngineModule {
+		return true
+	}
 	for _, ms := range in.Assigned {
 		for _, m := range ms {
 			if m == module {

modules/mesh-grants/internal/grants/records.go

@@ -78,6 +78,11 @@ func Records(in Inputs) (buscompose.Records, []Gap) {
 			}
 		}
 	}
+	// The node-engine's own manifest, placed on every node (ADR 0563): its state, logs and streams alone, created by this
+	// part; it adds no principal, since each node's engine speaks as the node's account.
+	if m, ok := in.Manifests[buscompose.EngineModule]; ok {
+		out.Engine = &buscompose.Declared{Module: m.Module, State: bucketsOf(m), Logs: logsOf(m), Streams: streamsOf(m)}
+	}
 	return out, gaps
 }