terraform_deprecated_lookup.md

terraform_deprecated_lookup

Disallow deprecated lookup function usage without a default.

This rule is enabled by "recommended" preset.

Example

locals {
  map   = { a = 0 }
  value = lookup(local.map, "a")
}

$ tflint
1 issue(s) found:

Warning: [Fixable] Lookup with 2 arguments is deprecated (terraform_deprecated_lookup)

  on main.tf line 3:
   3:   value = lookup(local.map, "a")

Reference: https://github.com/terraform-linters/tflint-ruleset-terraform/blob/v0.5.0/docs/rules/terraform_deprecated_lookup.md

Why

Calling lookup with 2 arguments has been deprecated since Terraform v0.7. lookup(map, key) is equivalent to the native index syntax map[key]. lookup should only be used with the third default argument, even though it is optional for backward compatibility.

How To Fix

Use the native index syntax:

Example:

locals {
  map   = { a = 0 }
  value = lookup(local.map, "a")
}

Change this to:

locals {
  map   = { a = 0 }
  value = local.map["a"]
}