fix: Sending an invalid message to the server raises an InternalServerError

* When the json is converted to an Object, internal validation may throw
  IllegalArgumentException which should be converted in a proper error.

This fixes issue#512

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

Author: ehsavoie

http-client/src/main/java/io/a2a/client/http/A2ACardResolver.java

@@ -8,6 +8,7 @@
 
 import io.a2a.grpc.utils.JSONRPCUtils;
 import io.a2a.grpc.utils.ProtoUtils;
+import io.a2a.json.JsonProcessingException;
 import io.a2a.spec.A2AClientError;
 import io.a2a.spec.A2AClientJSONError;
 import io.a2a.spec.AgentCard;
@@ -105,13 +106,10 @@ public AgentCard getAgentCard() throws A2AClientError, A2AClientJSONError {
 
         try {
             io.a2a.grpc.AgentCard.Builder agentCardBuilder = io.a2a.grpc.AgentCard.newBuilder();
-            JSONRPCUtils.parseJsonString(body, agentCardBuilder);
+            JSONRPCUtils.parseJsonString(body, agentCardBuilder, null);
             return ProtoUtils.FromProto.agentCard(agentCardBuilder);
-        } catch (JSONRPCError e) {
+        } catch (JSONRPCError | JsonProcessingException e) {
             throw new A2AClientJSONError("Could not unmarshal agent card response", e);
         }
-
     }
-
-
 }

http-client/src/test/java/io/a2a/client/http/A2ACardResolverTest.java

@@ -12,6 +12,7 @@
 import com.google.protobuf.util.JsonFormat;
 import io.a2a.grpc.utils.JSONRPCUtils;
 import io.a2a.grpc.utils.ProtoUtils;
+import io.a2a.json.JsonProcessingException;
 import io.a2a.spec.A2AClientError;
 import io.a2a.spec.A2AClientJSONError;
 import io.a2a.spec.AgentCard;
@@ -79,9 +80,9 @@ public void testGetAgentCardSuccess() throws Exception {
         assertEquals(expected, requestCardString);
     }
 
-    private AgentCard unmarshalFrom(String body) {
+    private AgentCard unmarshalFrom(String body) throws JsonProcessingException {
         io.a2a.grpc.AgentCard.Builder agentCardBuilder = io.a2a.grpc.AgentCard.newBuilder();
-        JSONRPCUtils.parseJsonString(body, agentCardBuilder);
+        JSONRPCUtils.parseJsonString(body, agentCardBuilder, null);
         return ProtoUtils.FromProto.agentCard(agentCardBuilder);
     }
 

reference/jsonrpc/src/main/java/io/a2a/server/apps/quarkus/A2AServerRoutes.java

@@ -6,6 +6,7 @@
 import static jakarta.ws.rs.core.MediaType.APPLICATION_JSON;
 import static jakarta.ws.rs.core.MediaType.SERVER_SENT_EVENTS;
 
+import com.google.gson.JsonSyntaxException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -39,6 +40,7 @@
 import io.a2a.spec.GetTaskPushNotificationConfigResponse;
 import io.a2a.spec.GetTaskRequest;
 import io.a2a.spec.GetTaskResponse;
+import io.a2a.spec.IdJsonMappingException;
 import io.a2a.spec.InternalError;
 import io.a2a.spec.InvalidParamsJsonMappingException;
 import io.a2a.spec.JSONParseError;
@@ -113,12 +115,12 @@ public void invokeJSONRPCHandler(@Body String body, RoutingContext rc) {
             error = new JSONRPCErrorResponse(e.getId(), new io.a2a.spec.InvalidParamsError(null, e.getMessage(), null));
         } catch (MethodNotFoundJsonMappingException e) {
             error = new JSONRPCErrorResponse(e.getId(), new io.a2a.spec.MethodNotFoundError(null, e.getMessage(), null));
-        } catch (io.a2a.spec.IdJsonMappingException e) {
+        } catch (IdJsonMappingException e) {
             error = new JSONRPCErrorResponse(e.getId(), new io.a2a.spec.InvalidRequestError(null, e.getMessage(), null));
         } catch (JsonMappingException e) {
             // General JsonMappingException - treat as InvalidRequest
             error = new JSONRPCErrorResponse(new io.a2a.spec.InvalidRequestError(null, e.getMessage(), null));
-        } catch (com.google.gson.JsonSyntaxException e) {
+        } catch (JsonSyntaxException e) {
             error = new JSONRPCErrorResponse(new JSONParseError(e.getMessage()));
         } catch (JsonProcessingException e) {
             error = new JSONRPCErrorResponse(new JSONParseError(e.getMessage()));