when no code change, revalidation_function should not result in terraform state change

[jackykwan-eventx]

Technical Details

• OS: ubuntu 20.04
• Terraform Version: 1.7.5
• Provider Version hashicorp/aws 5.34.0
• Module Version >= 2.0.0, < 3.0.0
• Module Affected: tf-aws-open-next-zone
• Deployment Model: Single zone

Describe the bug

When no code change and do terraform plan again, the module.revalidation_function.aws_lambda_function.lambda_function will be updated in-place

Steps to Reproduce

Steps to reproduce the behaviour:

1. deploy any nextjs project
2. keep no code change / build change
3. run terraform plan
4. it will show

  ~ resource "aws_lambda_function" "lambda_function" {
        id                             = "dummy"
      ~ qualified_arn                  = "arn:aws:lambda:region:accountId:function:prefix-revalidation-function:1" -> (known after apply)
      ~ qualified_invoke_arn           = "arn:aws:apigateway:region:lambda:path/2015-03-31/functions/arn:aws:lambda:region:accountId:function:prefix-revalidation-function:1/invocations" -> (known after apply)
        tags                           = {}
      ~ version                        = "1" -> (known after apply)
        # (19 unchanged attributes hidden)

        # (4 unchanged blocks hidden)
    }

  # module.moduleName.module.revalidation_function.terraform_data.update_alias[0] must be replaced
-/+ resource "terraform_data" "update_alias" {
      ~ id               = "dummy" -> (known after apply)
      ~ triggers_replace = [
          - "1",
          + (known after apply),
            "stable",
        ]
    }

Plan: 1 to add, 1 to change, 1 to destroy.

Expected behaviour

Should be no state update

[RJPearson94]

Hey @jackykwan-eventx,

I have been able to replicate this issue although I have no clue why this happens, as the logic is the same as the other functions.
I need to dig a little deeper into this to see if the issue is with module/ terraform or there is something unusual with that function in particular as it appears the server and image optimisation functions don’t have the same behaviour.

Kind Regards
Rob

[jackykwan-eventx]

@RJPearson94 thank you so much

[RJPearson94]

I may not be able to resolve this.

As it appears, there are some quirks around timestamps and permissions on the zip files. Reading the following comments:

• source_code_hash does not update hashicorp/terraform-provider-aws#7385 (comment)
• source_code_hash does not update hashicorp/terraform-provider-aws#7385 (comment)
  this appears to be an issue experienced by multiple people.

Although I am confused about why it only affects the revalidation function, the other two are fine.
I will continue investigating to see if the is a fix for this

[RJPearson94]

It looks like this issue is still present in open next v3