google_sql_database_instance.settings.0.replication_type diff on "SYNCHRONOUS" value

[rileykarson]

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 me too comments, 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.
• If an issue is assigned to the modular-magician user, it is either in the process of being autogenerated, or is planned to be autogenerated soon. If an issue is assigned to a user, that user is claiming responsibility for the issue. If an issue is assigned to hashibot, a community member has claimed the issue already.

Terraform Version

This affects all Core versions, and all provider versions going back at least a few years.

Affected Resource(s)

• google_sql_database_instance

Terraform Configuration Files

resource "google_sql_database_instance" "master" {
  name             = "master-instance"
  database_version = "POSTGRES_11"
  region           = "us-central1"

  settings {
    # Second-generation instance tiers are based on the machine
    # type. See argument reference below.
    tier = "db-f1-micro"
  }
}

Debug Output

N/A - I haven't experienced this myself yet, likely due to a staggered rollout.

Panic Output

N/A

Expected Behavior

No diffs.

Actual Behavior

Terraform sees a diff on replication_type, eg:

+ replication_type            = "SYNCHRONOUS"

Steps to Reproduce

1. terraform apply

Important Factoids

Users should be able to work around this using lifecycle.ignore_changes, eg:

lifecycle {
  ignore_changes = [settings.0.replication_type]
}

That solution will continue to work even if the API behaviour change is reverted. You can also set the value explicitly to "" (eg replication_type = "") although this will cause a diff if the API returns "SYNCHRONOUS" once again.

References

• b/175317767

[deekthesqueak]

Here is the DEBUG output I got for this error
[WARN] Provider "registry.terraform.io/hashicorp/google" produced an invalid plan for module.my-gcp.google_sql_database_instance.main, but we are tolerating it because it is using the legacy plugin SDK.
The following problems may be the cause of any confusing errors from downstream operations:
- .settings[0].replication_type: planned value cty.StringVal("SYNCHRONOUS") does not match config value cty.NullVal(cty.String) nor prior value cty.StringVal("")
- .settings[0].location_preference: block count in plan (1) disagrees with count in config (0)
- .settings[0].backup_configuration: block count in plan (1) disagrees with count in config (0)

Setting replication_type = "" will also remove the diff when generating the plan

[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. If you feel I made an error 🤖 🙉 , please reach out to my human friends 👉 [email protected]. Thanks!