Fix a bug that new TPE does not support dict metrics (#4531)

nni/algorithms/hpo/tpe_tuner.py

@@ -22,6 +22,7 @@ from scipy.special import erf  # pylint: disable=no-name-in-module
 
 from nni.tuner import Tuner
 from nni.common.hpo_utils import OptimizeMode, format_search_space, deformat_parameters, format_parameters
+from nni.utils import extract_scalar_reward
 from . import random_tuner
 
 _logger = logging.getLogger('nni.tuner.tpe')
@@ -126,9 +127,11 @@ class TpeTuner(Tuner):
         self._running_params[parameter_id] = params
         return deformat_parameters(params, self.space)
 
-    def receive_trial_result(self, parameter_id, _parameters, loss, **kwargs):
-        if self.optimize_mode is OptimizeMode.Maximize:
-            loss = -loss
+    def receive_trial_result(self, parameter_id, _parameters, value, **kwargs):
+        if self.optimize_mode is OptimizeMode.Minimize:
+            loss = extract_scalar_reward(value)
+        else:
+            loss = -extract_scalar_reward(value)
         if self.liar:
             self.liar.update(loss)
         params = self._running_params.pop(parameter_id)

test/ut/sdk/test_builtin_tuners.py

@@ -58,6 +58,8 @@ class BuiltinTunersTestCase(TestCase):
         return receive
 
     def send_trial_result(self, tuner, parameter_id, parameters, metrics):
+        if parameter_id % 2 == 1:
+            metrics = {'default': metrics, 'extra': 'hello'}
         tuner.receive_trial_result(parameter_id, parameters, metrics)
         tuner.trial_end(parameter_id, True)