feat(router): add a block router for benchmarking

gnes/cli/parser.py

@@ -140,7 +140,6 @@ def set_composer_flask_parser(parser=None):
 def set_service_parser(parser=None):
     from ..service.base import SocketType, BaseService, ParallelType
     import random
-    import uuid
     if not parser:
         parser = set_base_parser()
     min_port, max_port = 49152, 65536

gnes/router/map.py

@@ -20,7 +20,22 @@
 from ..proto import gnes_pb2
 
 
+class BlockRouter(BaseMapRouter):
+    """Wait for 'sleep_sec' seconds and forward messages, useful for benchmark"""
+
+    def __init__(self, sleep_sec: int = 5, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.sleep_sec = sleep_sec
+
+    def apply(self, msg: 'gnes_pb2.Message', *args, **kwargs):
+        import time
+        time.sleep(self.sleep_sec)
+
+
 class PublishRouter(BaseMapRouter):
+    """Copy a message 'num_part' time and forward it, useful for PUB-SUB sockets.
+    'num_part' is an indicator for downstream sync-barrier, e.g. a ReduceRouter
+    """
 
     def __init__(self, num_part: int, *args, **kwargs):
         super().__init__(*args, **kwargs)