Round floats before encoding

server/config.py

@@ -124,8 +124,8 @@ def __init__(self):
         self.QUEUE_POP_DESIRED_MATCHES = 2.5
         # How many previous queue sizes to consider
         self.QUEUE_POP_TIME_MOVING_AVG_SIZE = 5
-        # The number of decimal places to use for float serialization
-        self.JSON_FLOAT_DIGITS_PRECISION = 2
+        # The maximum number of decimal places to use for float serialization
+        self.JSON_FLOAT_MAX_DIGITS = 2
 
         self._defaults = {
             key: value for key, value in vars(self).items() if key.isupper()

server/protocol/protocol.py

@@ -10,32 +10,17 @@
 
 
 class CustomJSONEncoder(json.JSONEncoder):
-    # taken from https://stackoverflow.com/a/60243503
+    # taken from https://stackoverflow.com/a/53798633
     def encode(self, o):
-        if isinstance(o, dict):
-            dict_content = []
-            for key, value in o.items():
-                # do not use precision for float dict keys
-                if (isinstance(key, int) or isinstance(key, float)):
-                    new_key = f'"{key}"'.lower()
-                elif key is None:
-                    new_key = '"null"'
-                elif isinstance(key, str):
-                    new_key = self.encode(key)
-                else:
-                    raise TypeError(
-                        'Keys must be str, int, float, bool or None, '
-                        f'not {key.__class__.__name__}',
-                    )
-                new_value = self.encode(value)
-                dict_content.append(f"{new_key}:{new_value}")
-            return "{" + ",".join(dict_content) + "}"
-        elif isinstance(o, (list, tuple)) and not isinstance(o, str):
-            return "[" + ",".join(map(self.encode, o)) + "]"
-        elif isinstance(o, float):
-            return f"{o:.{config.JSON_FLOAT_DIGITS_PRECISION}f}"
-        else:
-            return super().encode(o)
+        def round_floats(o):
+            if isinstance(o, float):
+                return round(o, config.JSON_FLOAT_MAX_DIGITS)
+            if isinstance(o, dict):
+                return {k: round_floats(v) for k, v in o.items()}
+            if isinstance(o, (list, tuple)):
+                return [round_floats(x) for x in o]
+            return o
+        return super().encode(round_floats(o))
 
 
 json_encoder = CustomJSONEncoder(separators=(",", ":"))

tests/integration_tests/test_game.py

@@ -310,7 +310,7 @@ async def test_game_ended_rates_game(lobby_server):
 async def test_game_ended_broadcasts_rating_update(
     lobby_server, channel, mocker,
 ):
-    mocker.patch("server.config.JSON_FLOAT_DIGITS_PRECISION", 4)
+    mocker.patch("server.config.JSON_FLOAT_MAX_DIGITS", 4)
     mq_proto_all = await connect_mq_consumer(
         lobby_server,
         channel,
@@ -620,7 +620,7 @@ async def test_ladder_game_draw_bug(lobby_server, database, mocker):
     their own ACU in order to kill the enemy ACU and be awarded a victory
     instead of a draw.
     """
-    mocker.patch("server.config.JSON_FLOAT_DIGITS_PRECISION", 13)
+    mocker.patch("server.config.JSON_FLOAT_MAX_DIGITS", 13)
     player1_id, proto1, player2_id, proto2 = await queue_players_for_matchmaking(lobby_server)
 
     msg1, msg2 = await asyncio.gather(*[

tests/unit_tests/test_protocol.py

@@ -262,9 +262,9 @@ async def test_read_when_disconnected(protocol):
 
 
 def test_json_encoder_float_serialization():
-    assert json_encoder.encode(123.0) == '123.00'
+    assert json_encoder.encode(123.0) == '123.0'
     assert json_encoder.encode(0.99) == '0.99'
-    assert json_encoder.encode(0.999) == '1.00'
+    assert json_encoder.encode(0.999) == '1.0'
 
 
 def test_json_encoder_encodes_server_messages():
@@ -305,7 +305,7 @@ def test_json_encoder_encodes_server_messages():
 
     for queue in expected_matchmaker_info_dict["queues"]:
         queue["queue_pop_time_delta"] = round(
-            queue["queue_pop_time_delta"], config.JSON_FLOAT_DIGITS_PRECISION,
+            queue["queue_pop_time_delta"], config.JSON_FLOAT_MAX_DIGITS,
         )
 
     assert new_encode(matchmaker_info_dict) == (