From 76e025dbbc35927b1884cd640408e9a18054d3c5 Mon Sep 17 00:00:00 2001
From: jochen <jschoubben@gmail.com>
Date: Wed, 4 Nov 2026 14:31:36 +0100
Subject: [PATCH] J2: a state read carries the time the bus wrote the value, as
 at (stdio.StateEntry.At)

Claude-Session: https://claude.ai/code/session_01JG73KJNrH5EgFXMKKYSrig
---
 node-tools/internal/bus/per_node.go           | 2 +-
 node-tools/internal/bus/state.go              | 4 +++-
 node-tools/internal/bus/state_pernode_test.go | 3 ++-
 node-tools/internal/bus/state_watch_test.go   | 2 +-
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/node-tools/internal/bus/per_node.go b/node-tools/internal/bus/per_node.go
index ba64d35..dae0580 100644
--- a/node-tools/internal/bus/per_node.go
+++ b/node-tools/internal/bus/per_node.go
@@ -33,7 +33,7 @@ func (c *Conn) perNodeGet(s StateIssued, key string) (*StateEntry, error) {
 	if err != nil || e == nil {
 		return nil, err
 	}
-	return &StateEntry{Key: e.Key(), Value: valueOf(e.Value()), Revision: e.Revision()}, nil
+	return &StateEntry{Key: e.Key(), Value: valueOf(e.Value()), Revision: e.Revision(), At: e.Created().UTC()}, nil
 }
 
 func (c *Conn) perNodeKeys(s StateIssued) ([]string, error) {
diff --git a/node-tools/internal/bus/state.go b/node-tools/internal/bus/state.go
index 935ddff..4e53368 100644
--- a/node-tools/internal/bus/state.go
+++ b/node-tools/internal/bus/state.go
@@ -39,6 +39,8 @@ type StateEntry struct {
 	Key      string          `json:"key"`
 	Value    json.RawMessage `json:"value"`
 	Revision uint64          `json:"revision"`
+	// At is when the bus wrote this value (the entry's created time), as stdio.StateEntry.At reads it.
+	At time.Time `json:"at,omitzero"`
 }
 
 // StateChange is one change a watch delivers: a key put, deleted, or expired (its own time to live, or the
@@ -134,7 +136,7 @@ func (c *Conn) StateGet(module, name, key string) (*StateEntry, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &StateEntry{Key: e.Key(), Value: valueOf(e.Value()), Revision: e.Revision()}, nil
+	return &StateEntry{Key: e.Key(), Value: valueOf(e.Value()), Revision: e.Revision(), At: e.Created().UTC()}, nil
 }
 
 // StateKept is one value a bucket still keeps for a key: a put, or a delete (a purge reads as one).
diff --git a/node-tools/internal/bus/state_pernode_test.go b/node-tools/internal/bus/state_pernode_test.go
index de04809..82baf52 100644
--- a/node-tools/internal/bus/state_pernode_test.go
+++ b/node-tools/internal/bus/state_pernode_test.go
@@ -10,6 +10,7 @@ import (
 	"strings"
 	"sync"
 	"testing"
+	"time"
 
 	"github.com/novox/mesh-tools/node-tools/internal/bus"
 	mt "github.com/novox/mesh-tools/node-tools/internal/meshtest"
@@ -47,7 +48,7 @@ func TestAPerNodeStateIsServedAcrossEveryNodesBucket(t *testing.T) {
 		return nil
 	})
 
-	if e, err := conn.StateGet("mesh-provisioner", "mesh-host.composed", "b.m2.f2"); err != nil || e == nil || e.Key != "b.m2.f2" {
+	if e, err := conn.StateGet("mesh-provisioner", "mesh-host.composed", "b.m2.f2"); err != nil || e == nil || e.Key != "b.m2.f2" || e.At.IsZero() || time.Since(e.At) > time.Minute {
 		t.Fatalf("get from the second node's bucket: %+v, %v", e, err)
 	}
 	if e, err := conn.StateGet("mesh-provisioner", "mesh-host.composed", "q.m.f"); err != nil || e != nil {
diff --git a/node-tools/internal/bus/state_watch_test.go b/node-tools/internal/bus/state_watch_test.go
index cb69445..b4a40a7 100644
--- a/node-tools/internal/bus/state_watch_test.go
+++ b/node-tools/internal/bus/state_watch_test.go
@@ -151,7 +151,7 @@ func TestAMembershipTheGrantsPartWroteWrappedIsServed(t *testing.T) {
 	if _, err := conn.StatePut("gitea", "repos", "novox.hq", []byte(`{"v":1}`)); err != nil {
 		t.Fatalf("the state the membership issues is refused: %v", err)
 	}
-	if e, err := conn.StateGet("gitea", "repos", "novox.hq"); err != nil || e == nil || string(e.Value) != `{"v":1}` {
+	if e, err := conn.StateGet("gitea", "repos", "novox.hq"); err != nil || e == nil || string(e.Value) != `{"v":1}` || e.At.IsZero() || time.Since(e.At) > time.Minute {
 		t.Errorf("the state reads back %+v, %v", e, err)
 	}
 	conn.Follow("pages")