autoscaling: set conflict between availability_zones and vpc_zone_identifier

[bendrucker]

Community Note

• Please vote on this pull request by adding a 👍 reaction to the original pull request comment to help the community and maintainers prioritize this request
• Please do not leave "+1" or other comments that do not add relevant new information or questions, they generate extra noise for pull request followers and do not help prioritize the request

This PR adds ConflictsWith to vpc_zone_identifier, ensuring that a user that has passed VPC subnet IDs does not also pass a set of AZ names. This configuration would have previously resulted in an error on apply and now will trigger and error during validation.

Relates to #9622

Release note for CHANGELOG:

Prevent `availability_zones` and `vpc_zone_identifier` from being specified together

[bflad]

Hi @bendrucker 👋 Thank you for submitting this change. Please note I've marked this as a breaking change, since it currently causes some existing acceptance testing to fail that previously succeeded:

--- FAIL: TestAccAWSAutoScalingGroup_classicVpcZoneIdentifier (4.08s)
    testing.go:669: Step 0 error: config is invalid: "vpc_zone_identifier": conflicts with availability_zones

--- FAIL: TestAccAWSAutoScalingGroup_emptyAvailabilityZones (23.59s)
    testing.go:669: Step 0 error: errors during apply:
        
        Error: "vpc_zone_identifier": conflicts with availability_zones

The test configurations with these are using empty lists with the arguments, e.g.

resource "aws_autoscaling_group" "test" {
  min_size = 0
  max_size = 0

  availability_zones   = []
  launch_configuration = "${aws_launch_configuration.test.name}"
  vpc_zone_identifier  = ["${aws_subnet.test.id}"]
}

Which the resource code is designed to only pass elements when there is more than 0, e.g.

https://github.com/terraform-providers/terraform-provider-aws/blob/8a8845ed183d2f084f356cb8631d09870d05d340/aws/resource_aws_autoscaling_group.go#L533

The Terraform Plugin SDK ConflictsWith behavior strictly checks argument existence; not the final semantics of the given configuration values. Given that we probably should implement this at the schema level so it does return a plan-time validation error, at the cost of forcing operators to specify null for missing lists instead [], I will put this our next major release milestone for future consideration.

[bendrucker]

Thank you! Rushed through this a bit and didn't have a chance to run the acceptance tests. Totally understand that this is breaking, I have a similar change or two (adding ConflictsWith) similarly queued up for the Google provider.

• Updated TestAccAWSAutoScalingGroup_classicVpcZoneIdentifier to not use an empty list for vpc_zone_identifiers
• Removed TestAccAWSAutoScalingGroup_emptyAvailabilityZones, which is now appears irrelevant

I can set up and actually run the tests later today.

It also seemed like DiffSuppressFunc wasn't necessary anymore but then started to doubt myself.

[bendrucker]

Verified that the remaining acceptance test passes:

make testacc TESTARGS='-run=TestAccAWSAutoScalingGroup_classicVpcZoneIdentifier'

[bflad]

After minor adjustments to fix another test configuration that snuck in with the conflicting arguments, LGTM, thanks @bendrucker 🚀

Output from acceptance testing:

--- PASS: TestAccAWSAutoScalingGroup_ALB_TargetGroups (149.76s)
--- PASS: TestAccAWSAutoScalingGroup_ALB_TargetGroups_ELBCapacity (305.03s)
--- PASS: TestAccAWSAutoScalingGroup_autoGeneratedName (48.42s)
--- PASS: TestAccAWSAutoScalingGroup_basic (263.71s)
--- PASS: TestAccAWSAutoScalingGroup_classicVpcZoneIdentifier (110.01s)
--- PASS: TestAccAWSAutoScalingGroup_enablingMetrics (201.08s)
--- PASS: TestAccAWSAutoScalingGroup_initialLifecycleHook (343.64s)
--- PASS: TestAccAWSAutoScalingGroup_launchTemplate (40.12s)
--- PASS: TestAccAWSAutoScalingGroup_LaunchTemplate_IAMInstanceProfile (61.25s)
--- PASS: TestAccAWSAutoScalingGroup_launchTemplate_update (139.49s)
--- PASS: TestAccAWSAutoScalingGroup_launchTempPartitionNum (45.25s)
--- PASS: TestAccAWSAutoScalingGroup_LoadBalancers (703.48s)
--- PASS: TestAccAWSAutoScalingGroup_MaxInstanceLifetime (79.42s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy (266.34s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_OnDemandAllocationStrategy (106.47s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_OnDemandBaseCapacity (79.45s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_OnDemandPercentageAboveBaseCapacity (48.15s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_SpotAllocationStrategy (96.45s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_SpotInstancePools (72.86s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_SpotMaxPrice (77.33s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_InstancesDistribution_UpdateToZeroOnDemandBaseCapacity (45.55s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_LaunchTemplate_LaunchTemplateSpecification_LaunchTemplateName (52.49s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_LaunchTemplate_LaunchTemplateSpecification_Version (73.51s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_LaunchTemplate_Override_InstanceType (76.41s)
--- PASS: TestAccAWSAutoScalingGroup_MixedInstancesPolicy_LaunchTemplate_Override_WeightedCapacity (161.24s)
--- PASS: TestAccAWSAutoScalingGroup_namePrefix (55.45s)
--- PASS: TestAccAWSAutoScalingGroup_serviceLinkedRoleARN (48.37s)
--- PASS: TestAccAWSAutoScalingGroup_suspendingProcesses (206.53s)
--- PASS: TestAccAWSAutoScalingGroup_tags (261.72s)
--- PASS: TestAccAWSAutoScalingGroup_TargetGroupArns (185.94s)
--- PASS: TestAccAWSAutoScalingGroup_terminationPolicies (133.73s)
--- PASS: TestAccAWSAutoScalingGroup_VpcUpdates (76.21s)
--- PASS: TestAccAWSAutoScalingGroup_WithLoadBalancer (339.36s)
--- PASS: TestAccAWSAutoScalingGroup_WithLoadBalancer_ToTargetGroup (332.66s)
--- PASS: TestAccAWSAutoScalingGroup_withMetrics (129.58s)
--- PASS: TestAccAWSAutoScalingGroup_withPlacementGroup (168.23s)

[bendrucker]

Thank you!

[ghost]

This has been released in version 3.0.0 of the Terraform AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template for triage. Thanks!

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!