feat(api): add patch endpoint to update issuer label

pkg/api/postage.go

@@ -496,6 +496,45 @@ func (s *Service) estimateBatchTTL(batch *postage.Batch) (int64, error) {
 	return ttl.Int64(), nil
 }
 
+type postageLabelUpdateRequest struct {
+	Label string `json:"label"`
+}
+
+func (s *Service) postageUpdateLabelHandler(w http.ResponseWriter, r *http.Request) {
+	logger := s.logger.WithName("patch_stamp").Build()
+
+	paths := struct {
+		BatchID []byte `map:"batch_id" validate:"required,len=32"`
+	}{}
+	if response := s.mapStructure(mux.Vars(r), &paths); response != nil {
+		response("invalid path params", logger, w)
+		return
+	}
+	hexBatchID := hex.EncodeToString(paths.BatchID)
+
+	body := postageLabelUpdateRequest{}
+	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+		logger.Debug("patch stamp: decode body failed", "batch_id", hexBatchID, "error", err)
+		logger.Error(nil, "patch stamp: decode body failed")
+		jsonhttp.BadRequest(w, "invalid request body")
+		return
+	}
+
+	if err := s.post.UpdateIssuerLabel(paths.BatchID, body.Label); err != nil {
+		logger.Debug("patch stamp: update label failed", "batch_id", hexBatchID, "error", err)
+		logger.Error(nil, "patch stamp: update label failed")
+		switch {
+		case errors.Is(err, postage.ErrNotFound):
+			jsonhttp.NotFound(w, "issuer does not exist")
+		default:
+			jsonhttp.InternalServerError(w, "cannot update label")
+		}
+		return
+	}
+
+	jsonhttp.OK(w, nil)
+}
+
 func (s *Service) postageTopUpHandler(w http.ResponseWriter, r *http.Request) {
 	logger := s.logger.WithName("patch_stamp_topup").Build()
 

pkg/api/postage_test.go

@@ -1198,3 +1198,121 @@ func Test_postageDiluteHandler_invalidInputs(t *testing.T) {
 		})
 	}
 }
+
+func TestPostageUpdateLabelStamp(t *testing.T) {
+	t.Parallel()
+
+	batchID := batchOk
+	batchIDStr := batchOkStr
+	updatePath := "/stamps/" + batchIDStr
+
+	t.Run("ok", func(t *testing.T) {
+		t.Parallel()
+
+		si := postage.NewStampIssuer("original", "test identity", batchID, big.NewInt(3), 24, 6, 1000, false)
+		mp := mockpost.New(mockpost.WithIssuer(si))
+		ts, _, _, _ := newTestServer(t, testServerOptions{
+			Post: mp,
+		})
+
+		jsonhttptest.Request(t, ts, http.MethodPatch, updatePath, http.StatusOK,
+			jsonhttptest.WithRequestHeader("Content-Type", "application/json"),
+			jsonhttptest.WithRequestBody(bytes.NewBufferString(`{"label":"updated"}`)),
+			jsonhttptest.WithExpectedJSONResponse(jsonhttp.StatusResponse{Code: http.StatusOK, Message: "OK"}),
+		)
+	})
+
+	t.Run("not-found", func(t *testing.T) {
+		t.Parallel()
+
+		mp := mockpost.New()
+		ts, _, _, _ := newTestServer(t, testServerOptions{
+			Post: mp,
+		})
+
+		jsonhttptest.Request(t, ts, http.MethodPatch, updatePath, http.StatusNotFound,
+			jsonhttptest.WithRequestHeader("Content-Type", "application/json"),
+			jsonhttptest.WithRequestBody(bytes.NewBufferString(`{"label":"updated"}`)),
+			jsonhttptest.WithExpectedJSONResponse(jsonhttp.StatusResponse{Code: http.StatusNotFound, Message: "issuer does not exist"}),
+		)
+	})
+
+	t.Run("invalid-body", func(t *testing.T) {
+		t.Parallel()
+
+		si := postage.NewStampIssuer("original", "test identity", batchID, big.NewInt(3), 24, 6, 1000, false)
+		mp := mockpost.New(mockpost.WithIssuer(si))
+		ts, _, _, _ := newTestServer(t, testServerOptions{
+			Post: mp,
+		})
+
+		jsonhttptest.Request(t, ts, http.MethodPatch, updatePath, http.StatusBadRequest,
+			jsonhttptest.WithRequestHeader("Content-Type", "application/json"),
+			jsonhttptest.WithRequestBody(bytes.NewBufferString(`not-json`)),
+			jsonhttptest.WithExpectedJSONResponse(jsonhttp.StatusResponse{Code: http.StatusBadRequest, Message: "invalid request body"}),
+		)
+	})
+}
+
+//nolint:tparallel
+func Test_postageUpdateLabelHandler_invalidInputs(t *testing.T) {
+	t.Parallel()
+
+	client, _, _, _ := newTestServer(t, testServerOptions{})
+
+	tests := []struct {
+		name    string
+		batchID string
+		want    jsonhttp.StatusResponse
+	}{{
+		name:    "batch_id - odd hex string",
+		batchID: "123",
+		want: jsonhttp.StatusResponse{
+			Code:    http.StatusBadRequest,
+			Message: "invalid path params",
+			Reasons: []jsonhttp.Reason{
+				{
+					Field: "batch_id",
+					Error: api.ErrHexLength.Error(),
+				},
+			},
+		},
+	}, {
+		name:    "batch_id - invalid hex character",
+		batchID: "123G",
+		want: jsonhttp.StatusResponse{
+			Code:    http.StatusBadRequest,
+			Message: "invalid path params",
+			Reasons: []jsonhttp.Reason{
+				{
+					Field: "batch_id",
+					Error: api.HexInvalidByteError('G').Error(),
+				},
+			},
+		},
+	}, {
+		name:    "batch_id - invalid length",
+		batchID: "1234",
+		want: jsonhttp.StatusResponse{
+			Code:    http.StatusBadRequest,
+			Message: "invalid path params",
+			Reasons: []jsonhttp.Reason{
+				{
+					Field: "batch_id",
+					Error: "want len:32",
+				},
+			},
+		},
+	}}
+
+	//nolint:paralleltest
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			jsonhttptest.Request(t, client, http.MethodPatch, "/stamps/"+tc.batchID, tc.want.Code,
+				jsonhttptest.WithRequestHeader("Content-Type", "application/json"),
+				jsonhttptest.WithRequestBody(bytes.NewBufferString(`{"label":"x"}`)),
+				jsonhttptest.WithExpectedJSONResponse(tc.want),
+			)
+		})
+	}
+}

pkg/api/router.go

@@ -593,7 +593,8 @@ func (s *Service) mountBusinessDebug() {
 		s.checkChainAvailability,
 		s.postageSyncStatusCheckHandler,
 		web.FinalHandler(jsonhttp.MethodHandler{
-			"GET": http.HandlerFunc(s.postageGetStampHandler),
+			"GET":   http.HandlerFunc(s.postageGetStampHandler),
+			"PATCH": http.HandlerFunc(s.postageUpdateLabelHandler),
 		})),
 	)
 

pkg/api/router_test.go

@@ -103,7 +103,7 @@ func TestEndpointOptions(t *testing.T) {
 				{"/wallet", []string{"GET"}, http.StatusNoContent},
 				{"/wallet/withdraw/{coin}", []string{"POST"}, http.StatusNoContent},
 				{"/stamps", []string{"GET"}, http.StatusNoContent},
-				{"/stamps/{batch_id}", []string{"GET"}, http.StatusNoContent},
+				{"/stamps/{batch_id}", []string{"GET", "PATCH"}, http.StatusNoContent},
 				{"/stamps/{batch_id}/buckets", []string{"GET"}, http.StatusNoContent},
 				{"/stamps/{amount}/{depth}", []string{"POST"}, http.StatusNoContent},
 				{"/stamps/topup/{batch_id}/{amount}", []string{"PATCH"}, http.StatusNoContent},
@@ -293,7 +293,7 @@ func TestEndpointOptions(t *testing.T) {
 				{"/wallet", nil, http.StatusForbidden},
 				{"/wallet/withdraw/{coin}", nil, http.StatusForbidden},
 				{"/stamps", []string{"GET"}, http.StatusNoContent},
-				{"/stamps/{batch_id}", []string{"GET"}, http.StatusNoContent},
+				{"/stamps/{batch_id}", []string{"GET", "PATCH"}, http.StatusNoContent},
 				{"/stamps/{batch_id}/buckets", []string{"GET"}, http.StatusNoContent},
 				{"/stamps/{amount}/{depth}", []string{"POST"}, http.StatusNoContent},
 				{"/stamps/topup/{batch_id}/{amount}", []string{"PATCH"}, http.StatusNoContent},
@@ -388,7 +388,7 @@ func TestEndpointOptions(t *testing.T) {
 				{"/wallet", nil, http.StatusForbidden},
 				{"/wallet/withdraw/{coin}", nil, http.StatusForbidden},
 				{"/stamps", []string{"GET"}, http.StatusNoContent},
-				{"/stamps/{batch_id}", []string{"GET"}, http.StatusNoContent},
+				{"/stamps/{batch_id}", []string{"GET", "PATCH"}, http.StatusNoContent},
 				{"/stamps/{batch_id}/buckets", []string{"GET"}, http.StatusNoContent},
 				{"/stamps/{amount}/{depth}", []string{"POST"}, http.StatusNoContent},
 				{"/stamps/topup/{batch_id}/{amount}", []string{"PATCH"}, http.StatusNoContent},

pkg/postage/mock/service.go

@@ -99,6 +99,19 @@ func (m *mockPostage) IssuerUsable(_ *postage.StampIssuer) bool {
 	return true
 }
 
+func (m *mockPostage) UpdateIssuerLabel(id []byte, label string) error {
+	m.issuerLock.Lock()
+	defer m.issuerLock.Unlock()
+
+	_, exists := m.issuersMap[string(id)]
+	if !exists {
+		return postage.ErrNotFound
+	}
+	// label is local metadata only, real persistence is handled by the service implementation.
+	_ = label
+	return nil
+}
+
 func (m *mockPostage) HandleCreate(_ *postage.Batch, _ *big.Int) error { return nil }
 
 func (m *mockPostage) HandleTopUp(_ []byte, _ *big.Int) {}

pkg/postage/service.go

@@ -46,6 +46,7 @@ type Service interface {
 	StampIssuers() []*StampIssuer
 	GetStampIssuer([]byte) (*StampIssuer, func() error, error)
 	IssuerUsable(*StampIssuer) bool
+	UpdateIssuerLabel([]byte, string) error
 	BatchEventListener
 	BatchExpiryHandler
 	io.Closer
@@ -247,6 +248,20 @@ func (ps *service) GetStampIssuer(batchID []byte) (*StampIssuer, func() error, e
 	return nil, nil, ErrNotFound
 }
 
+// UpdateIssuerLabel updates the label of the stamp issuer with the given batch ID and persists the change.
+func (ps *service) UpdateIssuerLabel(batchID []byte, label string) error {
+	ps.mtx.Lock()
+	defer ps.mtx.Unlock()
+
+	for _, st := range ps.issuers {
+		if bytes.Equal(batchID, st.data.BatchID) {
+			st.data.Label = label
+			return ps.save(st)
+		}
+	}
+	return ErrNotFound
+}
+
 // save persists the specified stamp issuer to the stamperstore.
 func (ps *service) save(st *StampIssuer) error {
 	st.mtx.Lock()