mesh-provisioner-client takes a module off the node when its assignment is ended (issue 1098)

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

@@ -445,6 +445,9 @@ func (c *Client) take(s *state, u update) []string {
 		// A kind's answer moves what every module waits on.
 		return sortedKeys(s.plans)
 	case AssignmentsBucket:
+		// A value that is not a standing assignment (ended, or in a state: ADR 0408 clause 4) is read as a removed
+		// key, so the module leaves the machine as it does when the key goes (issue 1098).
+		gone = gone || !standingValue(e.Value())
 		// Whom it binds, whichever machine's it is: a provider here listing its consumers is filled again.
 		var providers []string
 		if takeBinds(s, key, e.Value(), gone) {

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/ended_test.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"testing"
+	"time"
+)
+
+// Issue 1098: a value of the assignments bucket with `ended` set takes the module off the node exactly as a removed
+// key does, and a value with the fields the controller adds to an assignment (build, commit, rollout, unknown ones)
+// is read under the same key.
+func TestNatsAnEndedAssignmentTakesAModuleOffTheNodeLikeARemovedKey(t *testing.T) {
+	b := startBus(t)
+	heard := b.listen(t)
+	e := startEngine(t, map[string]string{dunstrc: "owned"})
+	b.config(t, "dunst", "font-size", "13")
+	p := dunst(t)
+	b.assign(t, "dunst", p)
+	aClient(t, b, e, t.TempDir(), time.Hour)
+	eventually(t, "the needs are recorded", func() bool { return len(b.keys(t, NeedsBucket, node+".dunst.")) == 2 })
+
+	b.put(t, AssignmentsBucket, node+".dunst", fmt.Sprintf(`{"node":%q,"module":"dunst","assigned":"2026-10-14T20:00:00Z",`+
+		`"build":"b-1","commit":"abc","rollout":"r-1","ended":"2026-10-18T01:00:00Z",`+
+		`"provisioning":%s}`, node, planJSON(t, p)))
+	eventually(t, "its needs go", func() bool { return len(b.keys(t, NeedsBucket, node+".dunst.")) == 0 })
+	eventually(t, "its report goes", func() bool { return len(b.keys(t, AppliedBucket, node+".dunst")) == 0 })
+	eventually(t, "prov.applied says it is removed", func() bool {
+		r, _ := heard.last("dunst")
+		return r.Status == StatusRemoved
+	})
+}
+
+func TestNatsAnAssignmentWithTheNewFieldsIsFilledUnderTheSameKey(t *testing.T) {
+	b := startBus(t)
+	e := startEngine(t, map[string]string{dunstrc: "owned"})
+	b.config(t, "dunst", "font-size", "13")
+	p := dunst(t)
+	b.assign(t, "dunst", p)
+	aClient(t, b, e, t.TempDir(), time.Hour)
+	eventually(t, "the needs are recorded", func() bool { return len(b.keys(t, NeedsBucket, node+".dunst.")) == 2 })
+	b.put(t, AssignmentsBucket, node+".dunst", fmt.Sprintf(`{"node":%q,"module":"dunst","assigned":"2026-10-14T20:00:00Z",`+
+		`"build":"b-1","artifact":{"name":"dunst","version":"1"},"commit":"abc","rollout":"r-1",`+
+		`"since":"2026-10-18T00:00:00Z","ended":"","state":"","future":1,"provisioning":%s}`, node, planJSON(t, p)))
+	time.Sleep(300 * time.Millisecond)
+	if got := b.keys(t, NeedsBucket, node+".dunst."); len(got) != 2 {
+		t.Errorf("a value with the new fields took the module's needs away: %v", got)
+	}
+}
+
+func planJSON(t *testing.T, p Plan) []byte {
+	t.Helper()
+	raw, err := json.Marshal(p)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return raw
+}

modules/mesh-provisioner-client/cmd/mesh-provisioner-client/plan.go

@@ -29,6 +29,25 @@ type Assignment struct {
 	Provisioning json.RawMessage `json:"provisioning,omitempty"`
 }
 
+// standingValue is whether an assignment's value is a standing assignment: neither `ended` (the module was taken off
+// its node) nor `state` (a pending one) is set. A value that does not parse is not decided here: planOf refuses it.
+func standingValue(value []byte) bool {
+	var v struct {
+		Ended json.RawMessage `json:"ended"`
+		State json.RawMessage `json:"state"`
+	}
+	if json.Unmarshal(value, &v) != nil {
+		return true
+	}
+	return !fieldSet(v.Ended) && !fieldSet(v.State)
+}
+
+// fieldSet is whether a field of an assignment's value carries something: not absent, null or empty.
+func fieldSet(f json.RawMessage) bool {
+	s := strings.TrimSpace(string(f))
+	return s != "" && s != "null" && s != `""`
+}
+
 // Plan is one module's plan on this node.
 type Plan struct {
 	Templates Templates         `json:"templates"`