Make SupportedHyperParameters optional. (#695)

Author: nadiaya

CHANGELOG.rst

@@ -6,6 +6,7 @@ CHANGELOG
 ======
 
 * feature: ``PipelineModel``: Create a Transformer from a PipelineModel
+* bug-fix: ``AlgorithmEstimator``: Make SupportedHyperParameters optional
 
 1.18.4
 ======

src/sagemaker/algorithm.py

@@ -375,20 +375,23 @@ def _validate_and_set_default_hyperparameters(self):
                     raise ValueError('Required hyperparameter: %s is not set' % name)
 
     def _parse_hyperparameters(self):
-        hyperparameters = self.algorithm_spec['TrainingSpecification']['SupportedHyperParameters']
         definitions = {}
-        for h in hyperparameters:
-            parameter_type = h['Type']
-            name = h['Name']
-            parameter_class, parameter_range = self._hyperparameter_range_and_class(
-                parameter_type, h
-            )
 
-            definitions[name] = {'spec': h}
-            if parameter_range:
-                definitions[name]['range'] = parameter_range
-            if parameter_class:
-                definitions[name]['class'] = parameter_class
+        training_spec = self.algorithm_spec['TrainingSpecification']
+        if 'SupportedHyperParameters' in training_spec:
+            hyperparameters = training_spec['SupportedHyperParameters']
+            for h in hyperparameters:
+                parameter_type = h['Type']
+                name = h['Name']
+                parameter_class, parameter_range = self._hyperparameter_range_and_class(
+                    parameter_type, h
+                )
+
+                definitions[name] = {'spec': h}
+                if parameter_range:
+                    definitions[name]['range'] = parameter_range
+                if parameter_class:
+                    definitions[name]['class'] = parameter_class
 
         return definitions
 

tests/unit/test_algorithm.py

@@ -913,3 +913,21 @@ def test_algorithm_encrypt_inter_container_traffic(sagemaker_session):
 
     encrypt_inter_container_traffic = estimator.encrypt_inter_container_traffic
     assert encrypt_inter_container_traffic is True
+
+
+def test_algorithm_no_required_hyperparameters(sagemaker_session):
+    some_algo = copy.deepcopy(DESCRIBE_ALGORITHM_RESPONSE)
+    del some_algo['TrainingSpecification']['SupportedHyperParameters']
+
+    sagemaker_session.sagemaker_client.describe_algorithm = Mock(return_value=some_algo)
+
+    # Calling AlgorithmEstimator() with unset required hyperparameters
+    # should fail if they are required.
+    # Pass training and hyperparameters channels. This should work
+    assert AlgorithmEstimator(
+        algorithm_arn='arn:aws:sagemaker:us-east-2:1234:algorithm/scikit-decision-trees',
+        role='SageMakerRole',
+        train_instance_type='ml.m4.2xlarge',
+        train_instance_count=1,
+        sagemaker_session=sagemaker_session,
+    )