[email protected] and Computed,Optional,ForceNew

[ewbankkit]

Community Note

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• The resources and data sources in this provider are generated from the CloudFormation schema, so they can only support the actions that the underlying schema supports. For this reason submitted bugs should be limited to defects in the generation and runtime code of the provider. Customizing behavior of the resource, or noting a gap in behavior are not valid bugs and should be submitted as enhancements to AWS via the Cloudformation Open Coverage Roadmap.

Relates #208.
Closes #222.
Closes #218.
Closes #242.
Closes #219.

[ewbankkit]

The problem is that now arn (a Computed-only attribute) shows a continual diff: hashicorp/terraform-plugin-framework#189.

  # awscc_logs_log_group.test will be updated in-place
  ~ resource "awscc_logs_log_group" "test" {
      ~ arn               = "arn:aws:logs:us-east-1:187416307283:log-group:ewbankkit-test:*" -> (known after apply)
      ~ id                = "ewbankkit-test" -> (known after apply)
      ~ retention_in_days = 30 -> 60
        # (1 unchanged attribute hidden)
    }

and terraform apply will fail:

% TF_LOG=WARN make testacc PKG_NAME=internal/aws/logs TESTARGS='-run=TestAccAWSLogsLogGroup_'
TF_ACC=1 go test ./internal/aws/logs -v -count 1 -parallel 20 -run=TestAccAWSLogsLogGroup_ -timeout 180m
=== RUN   TestAccAWSLogsLogGroup_basic
=== PAUSE TestAccAWSLogsLogGroup_basic
=== RUN   TestAccAWSLogsLogGroup_disappears
=== PAUSE TestAccAWSLogsLogGroup_disappears
=== RUN   TestAccAWSLogsLogGroup_update
=== PAUSE TestAccAWSLogsLogGroup_update
=== CONT  TestAccAWSLogsLogGroup_basic
=== CONT  TestAccAWSLogsLogGroup_update
=== CONT  TestAccAWSLogsLogGroup_disappears
2021/10/14 11:15:52 [WARN] Got error running Terraform: exit status 1

Error: AWS SDK Go Service Operation Unsuccessful

  with awscc_logs_log_group.test,
  on terraform_plugin_test.tf line 2, in resource "awscc_logs_log_group" "test":
   2: resource "awscc_logs_log_group" "test" {

Calling Cloud Control API service UpdateResource operation returned:
operation error CloudControl: UpdateResource, https response error
StatusCode: 400, RequestID: f1b24f45-bfd2-42e6-9f41-85a10c169110, api error
ValidationException: Invalid patch update: readOnlyProperties
[/properties/Arn] cannot be updated
=== CONT  TestAccAWSLogsLogGroup_update
    testcases.go:30: Step 3/3 error: Error running apply: exit status 1
        
        Error: AWS SDK Go Service Operation Unsuccessful
        
          with awscc_logs_log_group.test,
          on terraform_plugin_test.tf line 2, in resource "awscc_logs_log_group" "test":
           2: resource "awscc_logs_log_group" "test" {
        
        Calling Cloud Control API service UpdateResource operation returned:
        operation error CloudControl: UpdateResource, https response error
        StatusCode: 400, RequestID: f1b24f45-bfd2-42e6-9f41-85a10c169110, api error
        ValidationException: Invalid patch update: readOnlyProperties
        [/properties/Arn] cannot be updated
--- PASS: TestAccAWSLogsLogGroup_disappears (18.25s)
--- PASS: TestAccAWSLogsLogGroup_basic (20.11s)
--- FAIL: TestAccAWSLogsLogGroup_update (23.82s)
FAIL
FAIL	github.com/hashicorp/terraform-provider-awscc/internal/aws/logs	24.831s
FAIL
make: *** [testacc] Error 1

2021-10-14T12:10:59.975-0400 [DEBUG] provider.terraform-provider-awscc: Cloud Control API PatchDocument: value=[{"op":"replace","path":"/RetentionInDays","value":60},{"op":"remove","path":"/Arn"},{"op":"remove","path":"/ID"}] timestamp=2021-10-14T12:10:59.975-0400

[bflad]

Plan modifiers like hashicorp/terraform-plugin-framework#180 should help resolve Computed attributes that are continually showing a difference, when another attribute is changing. In particular, hashicorp/terraform-plugin-framework#180 (comment) should be fairly close to what should be applied to readOnlyProperties to enhance the plan output. It should also theoretically prevent this error:

ValidationException: Invalid patch update: readOnlyProperties
[/properties/Arn] cannot be updated

Since there will be no difference in values for those attributes.

However, even without those, an additional safety measure the provider could do during Update is to strip out any readOnlyProperties from the update API request, since it seems they will always generate this type of API error. That might obfuscate certain other problems though, unless there's some warning logs as well.

[ewbankkit]

Relates:

• Only set RequiresReplace if value has changed and config is non-null terraform-plugin-framework#203 - Use this idea for non-(Computed,Optional) replacement, otherwise if ANY attribute changes the resource will be replaced
• Add state preserving plan modifiers terraform-plugin-framework#204 - Use this idea to prevent all Computed attributes being set to Unknown in a plan. At minimum id and arn attributes (maybe any Computed attributes that are primary identifiers?) should use this plan modifier

[ewbankkit]

Superseded by #306.