fix: fixing the handling of historyLength being set to 0 by default in gRPC. (#436)

* Using int instead of Integer and setting the default value to 0.
* If historyLength == 0 then we should return the full history
* Removing the handling of null

Issue: #423

Fixes #423 🦕

Signed-off-by: Emmanuel Hugonnet <[email protected]>

Author: ehsavoie

client/transport/grpc/src/main/java/io/a2a/client/transport/grpc/GrpcTransport.java

@@ -1,9 +1,5 @@
 package io.a2a.client.transport.grpc;
 
-import static io.a2a.grpc.A2AServiceGrpc.A2AServiceBlockingV2Stub;
-import static io.a2a.grpc.A2AServiceGrpc.A2AServiceStub;
-import static io.a2a.grpc.utils.ProtoUtils.FromProto;
-import static io.a2a.grpc.utils.ProtoUtils.ToProto;
 import static io.a2a.util.Assert.checkNotNullParam;
 
 import java.util.List;
@@ -127,9 +123,7 @@ public Task getTask(TaskQueryParams request, @Nullable ClientCallContext context
 
         GetTaskRequest.Builder requestBuilder = GetTaskRequest.newBuilder();
         requestBuilder.setName("tasks/" + request.id());
-        if (request.historyLength() != null) {
-            requestBuilder.setHistoryLength(request.historyLength());
-        }
+        requestBuilder.setHistoryLength(request.historyLength());
         GetTaskRequest getTaskRequest = requestBuilder.build();
         PayloadAndHeaders payloadAndHeaders = applyInterceptors(io.a2a.spec.GetTaskRequest.METHOD, getTaskRequest,
                 agentCard, context);

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

@@ -125,7 +125,7 @@ public Task getTask(TaskQueryParams taskQueryParams, @Nullable ClientCallContext
                 agentCard, context);
         try {
             String url;
-            if (taskQueryParams.historyLength() != null) {
+            if (taskQueryParams.historyLength() > 0) {
                 url = agentUrl + String.format("/v1/tasks/%1s?historyLength=%2d", taskQueryParams.id(), taskQueryParams.historyLength());
             } else {
                 url = agentUrl + String.format("/v1/tasks/%1s", taskQueryParams.id());

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

@@ -122,9 +122,9 @@ public void getTask(RoutingContext rc) {
             if (taskId == null || taskId.isEmpty()) {
                 response = jsonRestHandler.createErrorResponse(new InvalidParamsError("bad task id"));
             } else {
-                Integer historyLength = null;
+                int historyLength = 0;
                 if (rc.request().params().contains("history_length")) {
-                    historyLength = Integer.valueOf(rc.request().params().get("history_length"));
+                    historyLength = Integer.parseInt(rc.request().params().get("history_length"));
                 }
                 response = jsonRestHandler.getTask(taskId, historyLength, context);
             }

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

@@ -4,6 +4,7 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyInt;
 import static org.mockito.ArgumentMatchers.anyString;
 import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
@@ -137,15 +138,15 @@ public void testGetTask_MethodNameSetInContext() {
         when(mockHttpResponse.getStatusCode()).thenReturn(200);
         when(mockHttpResponse.getContentType()).thenReturn("application/json");
         when(mockHttpResponse.getBody()).thenReturn("{test:value}");
-        when(mockRestHandler.getTask(anyString(), any(), any(ServerCallContext.class))).thenReturn(mockHttpResponse);
+        when(mockRestHandler.getTask(anyString(), anyInt(), any(ServerCallContext.class))).thenReturn(mockHttpResponse);
 
         ArgumentCaptor<ServerCallContext> contextCaptor = ArgumentCaptor.forClass(ServerCallContext.class);
 
         // Act
         routes.getTask(mockRoutingContext);
 
         // Assert
-        verify(mockRestHandler).getTask(eq("task123"), eq(null), contextCaptor.capture());
+        verify(mockRestHandler).getTask(eq("task123"), anyInt(), contextCaptor.capture());
         ServerCallContext capturedContext = contextCaptor.getValue();
         assertNotNull(capturedContext);
         assertEquals(GetTaskRequest.METHOD, capturedContext.getState().get(METHOD_NAME_KEY));

server-common/src/main/java/io/a2a/server/requesthandlers/DefaultRequestHandler.java

@@ -19,7 +19,6 @@
 import java.util.function.Supplier;
 
 import jakarta.enterprise.context.ApplicationScoped;
-import jakarta.enterprise.inject.Instance;
 import jakarta.inject.Inject;
 
 import io.a2a.server.ServerCallContext;
@@ -34,7 +33,6 @@
 import io.a2a.server.events.TaskQueueExistsException;
 import io.a2a.server.tasks.PushNotificationConfigStore;
 import io.a2a.server.tasks.PushNotificationSender;
-import io.a2a.server.tasks.TaskStateProvider;
 import io.a2a.server.tasks.ResultAggregator;
 import io.a2a.server.tasks.TaskManager;
 import io.a2a.server.tasks.TaskStore;
@@ -103,14 +101,14 @@ public Task onGetTask(TaskQueryParams params, ServerCallContext context) throws
             LOGGER.debug("No task found for {}. Throwing TaskNotFoundError", params.id());
             throw new TaskNotFoundError();
         }
-        if (params.historyLength() != null && task.getHistory() != null && params.historyLength() < task.getHistory().size()) {
+        if (task.getHistory() != null && params.historyLength() < task.getHistory().size()) {
             List<Message> history;
             if (params.historyLength() <= 0) {
-                history = new ArrayList<>();
+                history = task.getHistory();
             } else {
                 history = task.getHistory().subList(
                         task.getHistory().size() - params.historyLength(),
-                        task.getHistory().size() - 1);
+                        task.getHistory().size());
             }
 
             task = new Task.Builder(task)