feat(aws): add support for resizing ASGs with optional min/max/desired (

#2430)

* feat(aws): add support for resizing ASGs with optional min/max/desired

We need to replace ResizeAsgDescription.Capacity with something that has
optional (i.e. nullable) fields. ServerGroup.Capacity happens to have
exactly that.

* feat(aws): skip no-op resize ASG requests

clouddriver-aws/src/main/groovy/com/netflix/spinnaker/clouddriver/aws/deploy/description/ResizeAsgDescription.groovy

@@ -16,13 +16,12 @@
 
 package com.netflix.spinnaker.clouddriver.aws.deploy.description
 
-class ResizeAsgDescription extends AbstractAmazonCredentialsDescription {
+import com.netflix.spinnaker.clouddriver.model.ServerGroup
 
+class ResizeAsgDescription extends AbstractAmazonCredentialsDescription {
   String serverGroupName
   String region
-
-  Capacity capacity = new Capacity()
-
+  ServerGroup.Capacity capacity
   List<AsgTargetDescription> asgs = []
 
   @Deprecated
@@ -31,23 +30,12 @@ class ResizeAsgDescription extends AbstractAmazonCredentialsDescription {
   @Deprecated
   List<String> regions = []
 
-  static class Capacity {
-    int min
-    int max
-    int desired
-
-    @Override
-    String toString() {
-      return "min: $min, max: $max, desired: $desired"
-    }
-  }
-
   static class Constraints {
-    Capacity capacity
+    ServerGroup.Capacity capacity
   }
 
   static class AsgTargetDescription extends AsgDescription {
-    Capacity capacity = new Capacity()
+    ServerGroup.Capacity capacity = new ServerGroup.Capacity()
     Constraints constraints = new Constraints()
 
     @Override

clouddriver-aws/src/main/groovy/com/netflix/spinnaker/clouddriver/aws/deploy/ops/ResizeAsgAtomicOperation.groovy

@@ -24,6 +24,7 @@ import com.netflix.spinnaker.clouddriver.aws.deploy.description.ResizeAsgDescrip
 import com.netflix.spinnaker.clouddriver.aws.security.AmazonClientProvider
 import com.netflix.spinnaker.clouddriver.data.task.Task
 import com.netflix.spinnaker.clouddriver.data.task.TaskRepository
+import com.netflix.spinnaker.clouddriver.model.ServerGroup
 import com.netflix.spinnaker.clouddriver.orchestration.AtomicOperation
 import org.springframework.beans.factory.annotation.Autowired
 
@@ -57,9 +58,15 @@ class ResizeAsgAtomicOperation implements AtomicOperation<Void> {
 
   private void resizeAsg(String asgName,
                          String region,
-                         ResizeAsgDescription.Capacity capacity,
+                         ServerGroup.Capacity capacity,
                          ResizeAsgDescription.Constraints constraints) {
     task.updateStatus PHASE, "Beginning resize of ${asgName} in ${region} to ${capacity}."
+
+    if (capacity.min == null && capacity.max == null && capacity.desired == null) {
+      task.updateStatus PHASE, "Skipping resize of ${asgName} in ${region}, at least one field in ${capacity} needs to be non-null"
+      return
+    }
+
     def autoScaling = amazonClientProvider.getAutoScaling(description.credentials, region, true)
     def describeAutoScalingGroups = autoScaling.describeAutoScalingGroups(
       new DescribeAutoScalingGroupsRequest().withAutoScalingGroupNames(asgName)
@@ -71,6 +78,7 @@ class ResizeAsgAtomicOperation implements AtomicOperation<Void> {
 
     validateConstraints(constraints, describeAutoScalingGroups.getAutoScalingGroups().get(0))
 
+    // min, max and desired may be null
     def request = new UpdateAutoScalingGroupRequest().withAutoScalingGroupName(asgName)
         .withMinSize(capacity.min)
         .withMaxSize(capacity.max)

clouddriver-aws/src/test/groovy/com/netflix/spinnaker/clouddriver/aws/deploy/ops/ResizeAsgAtomicOperationUnitSpec.groovy

@@ -30,6 +30,10 @@ import spock.lang.Specification
 import spock.lang.Unroll
 
 class ResizeAsgAtomicOperationUnitSpec extends Specification {
+  def mockAutoScaling = Mock(AmazonAutoScaling)
+  def mockAmazonClientProvider = Mock(AmazonClientProvider) {
+    _ * getAutoScaling(_, _, true) >> { return mockAutoScaling }
+  }
 
   def setupSpec() {
     TaskRepository.threadLocalTask.set(Mock(Task))
@@ -38,14 +42,11 @@ class ResizeAsgAtomicOperationUnitSpec extends Specification {
   @Unroll
   void "should update ASG iff it exists and is not in the process of being deleted"() {
     setup:
-    def mockAutoScaling = Mock(AmazonAutoScaling)
-    def mockAmazonClientProvider = Mock(AmazonClientProvider)
-    mockAmazonClientProvider.getAutoScaling(_, _, true) >> mockAutoScaling
     def description = new ResizeAsgDescription(
       asgs: [[
         serverGroupName: "myasg-stack-v000",
         region         : "us-west-1",
-        capacity       : new ResizeAsgDescription.Capacity(
+        capacity       : new ServerGroup.Capacity(
           min    : 1,
           max    : 2,
           desired: 5
@@ -110,8 +111,46 @@ class ResizeAsgAtomicOperationUnitSpec extends Specification {
     capacity(0, 2, 3)    | 1          | 2          | 3              || true
   }
 
+  @Unroll
+  void "should support resize requests with only some fields to update (min: #minSize, max: #maxSize, desired: #desired)"() {
+    setup:
+    def description = new ResizeAsgDescription(
+      asgs: [[
+               serverGroupName: "myasg-stack-v000",
+               region         : "us-west-1",
+               capacity       : new ServerGroup.Capacity(min: minSize, max: maxSize, desired: desired)
+             ]]
+    )
+    def operation = new ResizeAsgAtomicOperation(description)
+    operation.amazonClientProvider = mockAmazonClientProvider
+
+    when:
+    operation.operate([])
+
+    then:
+    expectedOps * mockAutoScaling.describeAutoScalingGroups(_) >> new DescribeAutoScalingGroupsResult().withAutoScalingGroups(
+      new AutoScalingGroup().withAutoScalingGroupName("myasg-stack-v0001")
+    )
+
+    expectedOps * mockAutoScaling.updateAutoScalingGroup(_) >> {
+      request ->
+        assert request.size() == 1
+        assert request[0].minSize == minSize
+        assert request[0].maxSize == maxSize
+        assert request[0].desiredCapacity == desired
+    }
+
+    where:
+    minSize | maxSize | desired | expectedOps
+    42      | null    | null    | 1
+    null    | 42      | null    | 1
+    null    | null    | 42      | 1
+    0       | null    | null    | 1
+    0       | 0       | 0       | 1 // not the same as (null, null, null)
+    null    | null    | null    | 0
+  }
 
-  private static ResizeAsgDescription.Capacity capacity(int min, int max, int desired) {
-    return new ResizeAsgDescription.Capacity(min: min, max: max, desired: desired)
+  private static ServerGroup.Capacity capacity(int min, int max, int desired) {
+    return new ServerGroup.Capacity(min: min, max: max, desired: desired)
   }
 }

clouddriver-aws/src/test/groovy/com/netflix/spinnaker/clouddriver/aws/deploy/validators/ResizeAsgDescriptionValidatorSpec.groovy

@@ -20,10 +20,12 @@ import com.netflix.spinnaker.clouddriver.aws.TestCredential
 import com.netflix.spinnaker.clouddriver.aws.security.NetflixAmazonCredentials
 import com.netflix.spinnaker.clouddriver.deploy.DescriptionValidator
 import com.netflix.spinnaker.clouddriver.aws.deploy.description.ResizeAsgDescription
+import com.netflix.spinnaker.clouddriver.model.ServerGroup
 import org.springframework.validation.Errors
 import spock.lang.Shared
+import spock.lang.Specification
 
-class ResizeAsgDescriptionValidatorSpec {
+class ResizeAsgDescriptionValidatorSpec extends Specification {
 
   @Shared
   DescriptionValidator validator = new ResizeAsgDescriptionValidator()
@@ -34,7 +36,7 @@ class ResizeAsgDescriptionValidatorSpec {
       asgs: [new ResizeAsgDescription.AsgTargetDescription(
         serverGroupName: "foo",
         region: "us-west-1",
-        capacity: new ResizeAsgDescription.Capacity(min: 5, max: 3)
+        capacity: new ServerGroup.Capacity(min: 5, max: 3)
       )],
       credentials: Stub(NetflixAmazonCredentials)
     )
@@ -47,7 +49,7 @@ class ResizeAsgDescriptionValidatorSpec {
     1 * errors.rejectValue('capacity', _, ['5', '3'], _)
 
     when:
-    description.asgs[0].capacity = new ResizeAsgDescription.Capacity(min: 3, max: 5, desired: 7)
+    description.asgs[0].capacity = new ServerGroup.Capacity(min: 3, max: 5, desired: 7)
     validator.validate([], description, errors)
 
     then: