Adding PolicyType to scaling policy and implementing filtering in describe_policies (#797)

* Adding PolicyType to FakeScalingPolicy

* Implement filtering for AutoScalingBackend.describe_policies(...)

* Unit test for describe_policies fuction in autoscaling

moto/autoscaling/models.py

@@ -16,9 +16,10 @@ class InstanceState(object):
 
 
 class FakeScalingPolicy(object):
-    def __init__(self, name, adjustment_type, as_name, scaling_adjustment,
+    def __init__(self, name, policy_type, adjustment_type, as_name, scaling_adjustment,
                  cooldown, autoscaling_backend):
         self.name = name
+        self.policy_type = policy_type
         self.adjustment_type = adjustment_type
         self.as_name = as_name
         self.scaling_adjustment = scaling_adjustment
@@ -407,16 +408,19 @@ class AutoScalingBackend(BaseBackend):
             desired_capacity = int(desired_capacity)
         self.set_desired_capacity(group_name, desired_capacity)
 
-    def create_autoscaling_policy(self, name, adjustment_type, as_name,
+    def create_autoscaling_policy(self, name, policy_type, adjustment_type, as_name,
                                   scaling_adjustment, cooldown):
-        policy = FakeScalingPolicy(name, adjustment_type, as_name,
+        policy = FakeScalingPolicy(name, policy_type, adjustment_type, as_name,
                                    scaling_adjustment, cooldown, self)
 
         self.policies[name] = policy
         return policy
 
-    def describe_policies(self):
-        return list(self.policies.values())
+    def describe_policies(self, autoscaling_group_name=None, policy_names=None, policy_types=None):
+        return [policy for policy in self.policies.values()
+                if (not autoscaling_group_name or policy.as_name == autoscaling_group_name) and
+                    (not policy_names or policy.name in policy_names) and
+                    (not policy_types or policy.policy_type in policy_types)]
 
     def delete_policy(self, group_name):
         self.policies.pop(group_name, None)

moto/autoscaling/responses.py

@@ -120,6 +120,7 @@ class AutoScalingResponse(BaseResponse):
     def put_scaling_policy(self):
         policy = self.autoscaling_backend.create_autoscaling_policy(
             name=self._get_param('PolicyName'),
+            policy_type=self._get_param('PolicyType'),
             adjustment_type=self._get_param('AdjustmentType'),
             as_name=self._get_param('AutoScalingGroupName'),
             scaling_adjustment=self._get_int_param('ScalingAdjustment'),
@@ -129,7 +130,10 @@ class AutoScalingResponse(BaseResponse):
         return template.render(policy=policy)
 
     def describe_policies(self):
-        policies = self.autoscaling_backend.describe_policies()
+        policies = self.autoscaling_backend.describe_policies(
+            autoscaling_group_name=self._get_param('AutoScalingGroupName'),
+            policy_names=self._get_multi_param('PolicyNames.member'),
+            policy_types=self._get_multi_param('PolicyTypes.member'))
         template = self.response_template(DESCRIBE_SCALING_POLICIES_TEMPLATE)
         return template.render(policies=policies)
 
@@ -373,6 +377,7 @@ DESCRIBE_SCALING_POLICIES_TEMPLATE = """<DescribePoliciesResponse xmlns="http://
         <AdjustmentType>{{ policy.adjustment_type }}</AdjustmentType>
         <ScalingAdjustment>{{ policy.scaling_adjustment }}</ScalingAdjustment>
         <PolicyName>{{ policy.name }}</PolicyName>
+        <PolicyType>{{ policy.policy_type }}</PolicyType>
         <AutoScalingGroupName>{{ policy.as_name }}</AutoScalingGroupName>
         <Cooldown>{{ policy.cooldown }}</Cooldown>
         <Alarms/>

tests/test_autoscaling/test_autoscaling.py

@@ -524,3 +524,57 @@ def test_autoscaling_taqs_update_boto3():
         AutoScalingGroupNames=["test_asg"]
     )
     response['AutoScalingGroups'][0]['Tags'].should.have.length_of(2)
+
+@mock_autoscaling
+def test_autoscaling_describe_policies_boto3():
+    client = boto3.client('autoscaling', region_name='us-east-1')
+    _ = client.create_launch_configuration(
+        LaunchConfigurationName='test_launch_configuration'
+    )
+    _ = client.create_auto_scaling_group(
+        AutoScalingGroupName='test_asg',
+        LaunchConfigurationName='test_launch_configuration',
+        MinSize=0,
+        MaxSize=20,
+        DesiredCapacity=5,
+        Tags=[{
+            "ResourceId": 'test_asg',
+            "Key": 'test_key',
+            "Value": 'test_value',
+            "PropagateAtLaunch": True
+        }]
+    )
+
+    client.put_scaling_policy(
+        AutoScalingGroupName='test_asg',
+        PolicyName='test_policy_down',
+        PolicyType='SimpleScaling',
+        AdjustmentType='PercentChangeInCapacity',
+        ScalingAdjustment=-10,
+        Cooldown=60,
+        MinAdjustmentMagnitude=1)
+    client.put_scaling_policy(
+        AutoScalingGroupName='test_asg',
+        PolicyName='test_policy_up',
+        PolicyType='SimpleScaling',
+        AdjustmentType='PercentChangeInCapacity',
+        ScalingAdjustment=10,
+        Cooldown=60,
+        MinAdjustmentMagnitude=1)
+
+    response = client.describe_policies()
+    response['ScalingPolicies'].should.have.length_of(2)
+
+    response = client.describe_policies(AutoScalingGroupName='test_asg')
+    response['ScalingPolicies'].should.have.length_of(2)
+
+    response = client.describe_policies(PolicyTypes=['StepScaling'])
+    response['ScalingPolicies'].should.have.length_of(0)
+
+    response = client.describe_policies(
+        AutoScalingGroupName='test_asg',
+        PolicyNames=['test_policy_down'],
+        PolicyTypes=['SimpleScaling']
+    )
+    response['ScalingPolicies'].should.have.length_of(1)
+    response['ScalingPolicies'][0]['PolicyName'].should.equal('test_policy_down')