fix: When sending HTTP 400 Bad Request error message to the client, a…

…n error message may now be included in the client side exception. (serverpod#2703)

packages/serverpod/lib/src/server/server.dart

@@ -339,6 +339,9 @@ class Server {
       return;
     } else if (result is ResultStatusCode) {
       request.response.statusCode = result.statusCode;
+      if (result.message != null) {
+        request.response.writeln(result.message);
+      }
       await request.response.close();
       return;
     } else if (result is ExceptionResult) {

packages/serverpod_client/lib/src/serverpod_client_exception.dart

@@ -21,7 +21,11 @@ class ServerpodClientException implements Exception {
 /// to the server.
 class ServerpodClientBadRequest extends ServerpodClientException {
   /// Creates a Bad Request Exception
-  ServerpodClientBadRequest() : super('Bad request', HttpStatus.badRequest);
+  ServerpodClientBadRequest([String? message])
+      : super(
+          'Bad request${message != null && message != '' ? ': $message' : ''}',
+          HttpStatus.badRequest,
+        );
 }
 
 /// Thrown if the client fails to authenticate and is therefore

packages/serverpod_client/lib/src/serverpod_client_shared_private.dart

@@ -44,7 +44,7 @@ dynamic getExceptionFrom({
   }
 
   return switch (statusCode) {
-    HttpStatus.badRequest => ServerpodClientBadRequest(),
+    HttpStatus.badRequest => ServerpodClientBadRequest(data),
     HttpStatus.unauthorized => ServerpodClientUnauthorized(),
     HttpStatus.forbidden => ServerpodClientForbidden(),
     HttpStatus.notFound => ServerpodClientNotFound(),

packages/serverpod_client/test/exception_from_test.dart

@@ -87,7 +87,7 @@ void main() {
     });
 
     test('then the message is a bad request', () {
-      expect(exception.message, 'Bad request');
+      expect(exception.message, 'Bad request: malformed data');
     });
   });
 

tests/serverpod_test_server/test_integration/auth_core/auth_header_test.dart

@@ -137,6 +137,10 @@ void main() async {
       }
       expect(clientException, isNotNull);
       expect(clientException!.statusCode, equals(400));
+      expect(
+        clientException.message,
+        startsWith('Bad request: '),
+      );
     });
   });
 }