Feature Request: Allow self-referencing in datadog_monitor

[ghost]

This issue was originally opened by @hryamzik as hashicorp/terraform#18226. It was migrated here as a result of the provider split. The original body of the issue is below.

---

Terraform Version

Terraform v0.11.5
+ provider.datadog v1.0.3

Terraform Configuration Files

resource "datadog_monitor" "disk" {
  name                = "Disk"
  type                = "metric alert"
  query               = "avg(last_5m):avg:system.disk.in_use{device:/dev/ad1s1} > ${datadog_monitor.disk.thresholds.critical}"
  message             = "test"

  thresholds {
    warning           = 0.1
    critical          = 0.7
  }
}

Debug Output

Error: datadog_monitor.disk: datadog_monitor.disk: self reference not allowed: "datadog_monitor.disk.thresholds.critical"

Expected Behavior

Working without errors... The problem here is that critical must mach value in a queue so currently it has to be updated in two places for the same resource.

Steps to Reproduce

1. terraform init
2. terraform apply

References

• Self Variables hashicorp/terraform#1033
• Feature Request: Allow self-referencing in heroku_app configs hashicorp/terraform#15669
• Self variables are only valid on resources hashicorp/terraform#14684

[masci]

Allowing self references is a feature that should be added upstream.
In the meantime, you can use this workaround

locals {
  disk_critical = 0.8
}

resource "datadog_monitor" "disk" {
  name                = "Disk"
  type                = "metric alert"
  query               = "avg(last_5m):avg:system.disk.in_use{device:/dev/ad1s1} > ${local.disk_critical}"
  message             = "test"

  thresholds {
    warning           = 0.1
    critical          = "${local.disk_critical}"
  }
}

Closing this.

[coretemp]

Can this be reopened?

I want to link to the dashboard id in the message, but that is not allowed.

Error: datadog_monitor.mine: datadog_monitor.mine: self reference not allowed: "datadog_monitor.mine.id"

Why should it have to be added upstream? It's just a matter of creating a monitor and then changing it to inject the id.