Issue/#970 Prevent queue pop timer from becoming negative (#1014)

* Extract pop timer tests to their own file

* Add config value QUEUE_POP_TIME_MIN to set lower bound for pop timers

server/config.py

@@ -148,6 +148,8 @@ def __init__(self):
         self.MAP_POOL_RATING_SELECTION = "mean"
         # The maximum amount of time in seconds to wait between pops
         self.QUEUE_POP_TIME_MAX = 90
+        # The minimum amount of time in seconds to wait between pops
+        self.QUEUE_POP_TIME_MIN = 15
         # The number of possible matches we would like to have when the queue
         # pops. The queue pop time will be adjusted based on the current rate of
         # players queuing to try and hit this number.

server/matchmaker/pop_timer.py

@@ -84,6 +84,14 @@ def time_until_next_pop(self, num_queued: int, time_queued: float) -> float:
                 next_pop_time, self.queue.name, config.QUEUE_POP_TIME_MAX
             )
             return config.QUEUE_POP_TIME_MAX
+
+        if next_pop_time < config.QUEUE_POP_TIME_MIN:
+            self._logger.warning(
+                "Required time (%.2fs) for %s is lower than min pop time (%ds). ",
+                next_pop_time, self.queue.name, config.QUEUE_POP_TIME_MIN
+            )
+            return config.QUEUE_POP_TIME_MIN
+
         return next_pop_time
 
     def cancel(self):

tests/unit_tests/test_matchmaker_queue.py

@@ -8,7 +8,7 @@
 from hypothesis import strategies as st
 
 from server.config import config
-from server.matchmaker import CombinedSearch, MapPool, PopTimer, Search
+from server.matchmaker import CombinedSearch, MapPool, Search
 from server.players import PlayerState
 from server.rating import RatingType
 
@@ -276,49 +276,6 @@ def test_combined_search_attributes(matchmaker_players):
     assert search.failed_matching_attempts == 2
 
 
-def test_queue_time_until_next_pop(queue_factory):
-    team_size = 2
-    t1 = PopTimer(queue_factory(team_size=team_size))
-    t2 = PopTimer(queue_factory(team_size=team_size))
-
-    desired_players = config.QUEUE_POP_DESIRED_MATCHES * team_size * 2
-
-    assert t1.time_until_next_pop(0, 0) == config.QUEUE_POP_TIME_MAX
-    # If the desired number of players is not reached within the maximum waiting
-    # time, then the next round must wait for the maximum allowed time as well.
-    a1 = t1.time_until_next_pop(
-        num_queued=desired_players - 1,
-        time_queued=config.QUEUE_POP_TIME_MAX
-    )
-    assert a1 == config.QUEUE_POP_TIME_MAX
-
-    # If there are more players than expected, the time should drop
-    a2 = t1.time_until_next_pop(
-        num_queued=desired_players * 2,
-        time_queued=config.QUEUE_POP_TIME_MAX
-    )
-    assert a2 < a1
-
-    # Make sure that queue moving averages are calculated independently
-    assert t2.time_until_next_pop(0, 0) == config.QUEUE_POP_TIME_MAX
-
-
-def test_queue_pop_time_moving_average_size(queue_factory):
-    t1 = PopTimer(queue_factory())
-
-    for _ in range(100):
-        t1.time_until_next_pop(100, 1)
-
-    # The rate should be extremely high, meaning the pop time should be low
-    assert t1.time_until_next_pop(100, 1) < 1
-
-    for _ in range(config.QUEUE_POP_TIME_MOVING_AVG_SIZE):
-        t1.time_until_next_pop(0, 100)
-
-    # The rate should be extremely low, meaning the pop time should be high
-    assert t1.time_until_next_pop(0, 100) == config.QUEUE_POP_TIME_MAX
-
-
 @given(rating=st.integers())
 def test_queue_map_pools_empty(queue_factory, rating):
     queue = queue_factory()

tests/unit_tests/test_pop_timer.py

@@ -0,0 +1,45 @@
+from server.config import config
+from server.matchmaker import PopTimer
+
+
+def test_queue_time_until_next_pop(queue_factory):
+    team_size = 2
+    t1 = PopTimer(queue_factory(team_size=team_size))
+    t2 = PopTimer(queue_factory(team_size=team_size))
+
+    desired_players = config.QUEUE_POP_DESIRED_MATCHES * team_size * 2
+
+    assert t1.time_until_next_pop(0, 0) == config.QUEUE_POP_TIME_MAX
+    # If the desired number of players is not reached within the maximum waiting
+    # time, then the next round must wait for the maximum allowed time as well.
+    a1 = t1.time_until_next_pop(
+        num_queued=desired_players - 1,
+        time_queued=config.QUEUE_POP_TIME_MAX
+    )
+    assert a1 == config.QUEUE_POP_TIME_MAX
+
+    # If there are more players than expected, the time should drop
+    a2 = t1.time_until_next_pop(
+        num_queued=desired_players * 2,
+        time_queued=config.QUEUE_POP_TIME_MAX
+    )
+    assert a2 < a1
+
+    # Make sure that queue moving averages are calculated independently
+    assert t2.time_until_next_pop(0, 0) == config.QUEUE_POP_TIME_MAX
+
+
+def test_queue_pop_time_moving_average_size(queue_factory):
+    t1 = PopTimer(queue_factory())
+
+    for _ in range(100):
+        t1.time_until_next_pop(100, 1)
+
+    # The rate should be extremely high, meaning the pop time should be low
+    assert t1.time_until_next_pop(100, 1) == config.QUEUE_POP_TIME_MIN
+
+    for _ in range(config.QUEUE_POP_TIME_MOVING_AVG_SIZE):
+        t1.time_until_next_pop(0, 100)
+
+    # The rate should be extremely low, meaning the pop time should be high
+    assert t1.time_until_next_pop(0, 100) == config.QUEUE_POP_TIME_MAX