fix!: Add request body parameter to cancelTask method

Update cancelTask signature across REST transport and tests to include
the request body parameter, aligning with recent a2a.proto changes. Fixes

Signed-off-by: Emmanuel Hugonnet <ehugonne@redhat.com>

Author: ehsavoie

client/transport/rest/src/main/java/io/a2a/client/transport/rest/RestTransport.java

@@ -165,8 +165,7 @@ public Task getTask(TaskQueryParams taskQueryParams, @Nullable ClientCallContext
     @Override
     public Task cancelTask(TaskIdParams taskIdParams, @Nullable ClientCallContext context) throws A2AClientException {
         checkNotNullParam("taskIdParams", taskIdParams);
-        io.a2a.grpc.CancelTaskRequest.Builder builder = io.a2a.grpc.CancelTaskRequest.newBuilder();
-        builder.setId(taskIdParams.id());
+        io.a2a.grpc.CancelTaskRequest.Builder builder = io.a2a.grpc.CancelTaskRequest.newBuilder(ProtoUtils.ToProto.cancelTaskRequest(taskIdParams));
         PayloadAndHeaders payloadAndHeaders = applyInterceptors(CANCEL_TASK_METHOD, builder, agentCard, context);
         try {
             String httpResponseBody = sendPostRequest(Utils.buildBaseUrl(agentInterface, taskIdParams.tenant()) + String.format("/tasks/%1s:cancel", taskIdParams.id()), payloadAndHeaders);

reference/jsonrpc/src/test/java/io/a2a/server/apps/quarkus/A2AServerRoutesTest.java

@@ -417,7 +417,7 @@ public void testListTaskPushNotificationConfig_MethodNameSetInContext() {
             {
              "jsonrpc": "2.0",
              "id": "cd4c76de-d54c-436c-8b9f-4c2703648d64",
-             "method": "ListTaskPushNotificationConfig",
+             "method": "ListTaskPushNotificationConfigs",
              "params": {
               "taskId": "de38c76d-d54c-436c-8b9f-4c2703648d64",
               "pageSize": 0,

reference/rest/src/main/java/io/a2a/server/rest/quarkus/A2AServerRoutes.java

@@ -199,15 +199,15 @@ public void getTask(RoutingContext rc) {
     }
 
     @Route(regex = "^\\/(?<tenant>[^\\/]*\\/?)tasks\\/(?<taskId>[^/]+):cancel$", order = 1, methods = {Route.HttpMethod.POST}, type = Route.HandlerType.BLOCKING)
-    public void cancelTask(RoutingContext rc) {
+    public void cancelTask(@Body String body, RoutingContext rc) {
         String taskId = rc.pathParam("taskId");
         ServerCallContext context = createCallContext(rc, CANCEL_TASK_METHOD);
         HTTPRestResponse response = null;
         try {
             if (taskId == null || taskId.isEmpty()) {
                 response = jsonRestHandler.createErrorResponse(new InvalidParamsError("bad task id"));
             } else {
-                response = jsonRestHandler.cancelTask(context, extractTenant(rc), taskId);
+                response = jsonRestHandler.cancelTask(context, extractTenant(rc), body, taskId);
             }
         } catch (Throwable t) {
             if (t instanceof A2AError error) {

reference/rest/src/test/java/io/a2a/server/rest/quarkus/A2AServerRoutesTest.java

@@ -160,15 +160,15 @@ public void testCancelTask_MethodNameSetInContext() {
         when(mockHttpResponse.getStatusCode()).thenReturn(200);
         when(mockHttpResponse.getContentType()).thenReturn("application/json");
         when(mockHttpResponse.getBody()).thenReturn("{}");
-        when(mockRestHandler.cancelTask(any(ServerCallContext.class), anyString(), anyString())).thenReturn(mockHttpResponse);
+        when(mockRestHandler.cancelTask(any(ServerCallContext.class), anyString(), anyString(), anyString())).thenReturn(mockHttpResponse);
 
         ArgumentCaptor<ServerCallContext> contextCaptor = ArgumentCaptor.forClass(ServerCallContext.class);
 
         // Act
-        routes.cancelTask(mockRoutingContext);
+        routes.cancelTask("{\"id\":\"task123\"}", mockRoutingContext);
 
         // Assert
-        verify(mockRestHandler).cancelTask(contextCaptor.capture(), anyString(), eq("task123"));
+        verify(mockRestHandler).cancelTask(contextCaptor.capture(), anyString(), anyString(), eq("task123"));
         ServerCallContext capturedContext = contextCaptor.getValue();
         assertNotNull(capturedContext);
         assertEquals(CANCEL_TASK_METHOD, capturedContext.getState().get(METHOD_NAME_KEY));

transport/rest/src/main/java/io/a2a/transport/rest/handler/RestHandler.java

@@ -144,12 +144,29 @@ public HTTPRestResponse sendStreamingMessage(ServerCallContext context, String t
         }
     }
 
-    public HTTPRestResponse cancelTask(ServerCallContext context, String tenant, String taskId) {
+    public HTTPRestResponse cancelTask(ServerCallContext context, String tenant, String body, String taskId) {
         try {
             if (taskId == null || taskId.isEmpty()) {
                 throw new InvalidParamsError();
             }
-            TaskIdParams params = TaskIdParams.builder().id(taskId).tenant(tenant).build();
+            TaskIdParams params;
+            if (body != null && !body.isEmpty()) {
+                io.a2a.grpc.CancelTaskRequest.Builder request = io.a2a.grpc.CancelTaskRequest.newBuilder();
+                parseRequestBody(body, request);
+                request.setTenant(tenant);
+                if (!taskId.equals(request.getId())) {
+                    throw new InvalidParamsError();
+                }
+                params = ProtoUtils.FromProto.taskIdParams(request);
+            } else {
+                params = TaskIdParams.builder().id(taskId).tenant(tenant).build();
+            }
+            io.a2a.grpc.CancelTaskRequest.Builder request = io.a2a.grpc.CancelTaskRequest.newBuilder();
+            parseRequestBody(body, request);
+            request.setTenant(tenant);
+            if (!taskId.equals(request.getId())) {
+                throw new InvalidParamsError();
+            }
             Task task = requestHandler.onCancelTask(params, context);
             if (task != null) {
                 return createSuccessResponse(200, io.a2a.grpc.Task.newBuilder(ProtoUtils.ToProto.task(task)));

transport/rest/src/test/java/io/a2a/transport/rest/handler/RestHandlerTest.java

@@ -174,7 +174,8 @@ public void testCancelTaskSuccess() {
             agentEmitter.cancel();
         };
 
-        RestHandler.HTTPRestResponse response = handler.cancelTask(callContext, "", MINIMAL_TASK.id());
+        String requestBody = String.format("{\"id\":\"%s\"}", MINIMAL_TASK.id());
+        RestHandler.HTTPRestResponse response = handler.cancelTask(callContext, "", requestBody, MINIMAL_TASK.id());
 
         Assertions.assertEquals(200, response.getStatusCode());
         Assertions.assertEquals("application/json", response.getContentType());
@@ -185,7 +186,8 @@ public void testCancelTaskSuccess() {
     public void testCancelTaskNotFound() {
         RestHandler handler = new RestHandler(CARD, requestHandler, internalExecutor);
 
-        RestHandler.HTTPRestResponse response = handler.cancelTask(callContext, "", "nonexistent");
+        String requestBody = "{\"id\":\"nonexistent\"}";
+        RestHandler.HTTPRestResponse response = handler.cancelTask(callContext, "", requestBody, "nonexistent");
 
         Assertions.assertEquals(404, response.getStatusCode());
         Assertions.assertEquals("application/json", response.getContentType());