Show user_data diff on change

[sean-abbott]

Community Note

• Please vote on this issue by adding a 👍 reaction to the original issue 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 issue followers and do not help prioritize the request
• If you are interested in working on this issue or have submitted a pull request, please leave a comment

Description

user_data changes are often unexpected. I"d like to be able to see a diff so that I can evaluate if it's reasonable or not

New or Affected Resource(s)

aws_instance

[sblask]

I was very surprised that this isn't supported for instances because for launch templates it is. I thought I had made something wrong...

[rubber-ant]

an easy workaround

add

resource "null_resource" "dummy" {
  triggers = {
    file= file("${path.module}/cloudconfig.sh")
  }
}

Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
  ~ update in-place
-/+ destroy and then create replacement

Terraform will perform the following actions:


  # module.test_module.null_resource.dummy must be replaced
-/+ resource "null_resource" "dummy" {
      ~ id       = "6886541937855345911" -> (known after apply)
      ~ triggers = { # forces replacement
          ~ "file" = <<-EOT
                #!/bin/bash

[gdavison]

Because this will store different state in the user_data parameter, making this change is technically a breaking change. We can do this work as part of v6.0

[johnsonaj]

Closed by #42078