fix!: messageId should be required for a Message (#260)

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Fixes #<issue_number_goes_here> 🦕

Author: fjuma

server-common/src/test/java/io/a2a/server/agentexecution/RequestContextTest.java

@@ -23,6 +23,8 @@
 
 public class RequestContextTest {
 
+    private static final String MESSAGE_ID = "123";
+    
     @Test
     public void testInitWithoutParams() {
         RequestContext context = new RequestContext(null, null, null, null, null, null);
@@ -35,7 +37,7 @@ public void testInitWithoutParams() {
 
     @Test
     public void testInitWithParamsNoIds() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
         UUID taskId = UUID.fromString("00000000-0000-0000-0000-000000000001");
@@ -59,7 +61,7 @@ public void testInitWithParamsNoIds() {
     @Test
     public void testInitWithTaskId() {
         String taskId = "task-123";
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(taskId).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(taskId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
         RequestContext context = new RequestContext(mockParams, taskId, null, null, null, null);
@@ -71,7 +73,7 @@ public void testInitWithTaskId() {
     @Test
     public void testInitWithContextId() {
         String contextId = "context-456";
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).contextId(contextId).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).contextId(contextId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         RequestContext context = new RequestContext(mockParams, null, contextId, null, null, null);
 
@@ -83,7 +85,7 @@ public void testInitWithContextId() {
     public void testInitWithBothIds() {
         String taskId = "task-123";
         String contextId = "context-456";
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(taskId).contextId(contextId).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(taskId).contextId(contextId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         RequestContext context = new RequestContext(mockParams, taskId, contextId, null, null, null);
 
@@ -95,7 +97,7 @@ public void testInitWithBothIds() {
 
     @Test
     public void testInitWithTask() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
         var mockTask = new Task.Builder().id("task-123").contextId("context-456").status(new TaskStatus(TaskState.COMPLETED)).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
@@ -130,7 +132,7 @@ public void testAttachRelatedTask() {
     @Test
     public void testCheckOrGenerateTaskIdWithExistingTaskId() {
         String existingId = "existing-task-id";
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(existingId).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId(existingId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
         RequestContext context = new RequestContext(mockParams, null, null, null, null, null);
@@ -143,7 +145,7 @@ public void testCheckOrGenerateTaskIdWithExistingTaskId() {
     public void testCheckOrGenerateContextIdWithExistingContextId() {
         String existingId = "existing-context-id";
 
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).contextId(existingId).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).contextId(existingId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
         RequestContext context = new RequestContext(mockParams, null, null, null, null, null);
@@ -154,7 +156,7 @@ public void testCheckOrGenerateContextIdWithExistingContextId() {
 
     @Test
     public void testInitRaisesErrorOnTaskIdMismatch() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         var mockTask = new Task.Builder().id("task-123").contextId("context-456").status(new TaskStatus(TaskState.COMPLETED)).build();
 
@@ -166,7 +168,7 @@ public void testInitRaisesErrorOnTaskIdMismatch() {
 
     @Test
     public void testInitRaisesErrorOnContextIdMismatch() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         var mockTask = new Task.Builder().id("task-123").contextId("context-456").status(new TaskStatus(TaskState.COMPLETED)).build();
 
@@ -198,7 +200,7 @@ public void testMessagePropertyWithoutParams() {
 
     @Test
     public void testMessagePropertyWithParams() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
         RequestContext context = new RequestContext(mockParams, null, null, null, null, null);
@@ -210,7 +212,7 @@ public void testInitWithExistingIdsInMessage() {
         String existingTaskId = "existing-task-id";
         String existingContextId = "existing-context-id";
 
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart("")))
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart("")))
                 .taskId(existingTaskId).contextId(existingContextId).build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
 
@@ -222,7 +224,7 @@ public void testInitWithExistingIdsInMessage() {
 
     @Test
     public void testInitWithTaskIdAndExistingTaskIdMatch() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         var mockTask = new Task.Builder().id("task-123").contextId("context-456").status(new TaskStatus(TaskState.COMPLETED)).build();
 
@@ -235,7 +237,7 @@ public void testInitWithTaskIdAndExistingTaskIdMatch() {
 
     @Test
     public void testInitWithContextIdAndExistingContextIdMatch() {
-        var mockMessage = new Message.Builder().role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
+        var mockMessage = new Message.Builder().messageId(MESSAGE_ID).role(Message.Role.USER).parts(List.of(new TextPart(""))).taskId("task-123").contextId("context-456").build();
         var mockParams = new MessageSendParams.Builder().message(mockMessage).build();
         var mockTask = new Task.Builder().id("task-123").contextId("context-456").status(new TaskStatus(TaskState.COMPLETED)).build();
 

server-common/src/test/java/io/a2a/server/tasks/TaskUpdaterTest.java

@@ -25,8 +25,10 @@
 public class TaskUpdaterTest {
     public static final String TEST_TASK_ID = "test-task-id";
     public static final String TEST_TASK_CONTEXT_ID = "test-task-context-id";
+    private static final String TEST_MESSAGE_ID = "123";
 
     private static final Message SAMPLE_MESSAGE = new Message.Builder()
+            .messageId(TEST_MESSAGE_ID)
             .taskId(TEST_TASK_ID)
             .contextId(TEST_TASK_CONTEXT_ID)
             .parts(new TextPart("Test message"))

spec/src/main/java/io/a2a/spec/Message.java

@@ -55,9 +55,10 @@ public Message(@JsonProperty("role") Role role, @JsonProperty("parts") List<Part
         if (! kind.equals(MESSAGE)) {
             throw new IllegalArgumentException("Invalid Message");
         }
+        Assert.checkNotNullParam("messageId", messageId);
         this.role = role;
         this.parts = parts;
-        this.messageId = messageId == null ? UUID.randomUUID().toString() : messageId;
+        this.messageId = messageId;
         this.contextId = contextId;
         this.taskId = taskId;
         this.referenceTaskIds = referenceTaskIds;

transport/jsonrpc/src/test/java/io/a2a/transport/jsonrpc/handler/JSONRPCHandlerTest.java

@@ -718,6 +718,7 @@ public void testOnResubscribeExistingTaskSuccess() {
 
         // We need to send some events in order for those to end up in the queue
         Message message = new Message.Builder()
+                .messageId("123")
                 .taskId(MINIMAL_TASK.getId())
                 .contextId(MINIMAL_TASK.getContextId())
                 .role(Message.Role.AGENT)