replace function cannot do double backslashes

[llarsson]

I need to use the replace function to replace dots in a domain name with two backslashes. Sounds simple, right? Well, it is not. Terraform's replace function does not work entirely as advertised. See the following example:

variable "sub_domain" { default = "needs.double.backslashes.com"}

output "with_spaces_works" {
  value = "${replace(var.sub_domain, ".", "\\ \\.")}"
}

output "buggy" {
  value = "${replace(var.sub_domain, ".", "\\\\.")}"
}

output "doubling_does_not_work" {
  value = "${replace(var.sub_domain, ".", "\\\\\\\\.")}"
}

I would expect to have the value of "buggy" be needs\\.double\\.backslashes\\.com, but it is not. It is in fact needs\.double\.backslashes\.com.

The entire output from the example above (save it to a file, run terraform apply on it) is:

Outputs:

buggy = needs\.double\.backslashes\.com
doubling_does_not_work = needs\.double\.backslashes\.com
with_spaces_works = needs\ \.double\ \.backslashes\ \.com

Please fix this. :)

(My particular use case is that I need to feed a string like this into a JSON file and then into a regex parser, so I need to escape the periods twice.)

This is using Terraform 0.7.3.

[llarsson]

output "buggy_but_with_letters" {
  value = "${replace(var.sub_domain, ".", "AA.")}"
}

Shows that had backslash handling been more correct, it would not have been an issue.

Also, removing the period as in the following example is actually apparently a syntax error, which makes me believe that backslash handling is rather broken:

output "spilling" {
  value = "${replace(var.sub_domain, ".", "\\\\")}"
}

[mitchellh]

I'll look into this, feels like an HCL bug. Thanks for the easy repros. I haven't tried them yet but they're comprehensive here and give me faith.

[mitchellh]

This is fixed and explained here: hashicorp/hcl#150

Unfortunately this has a chance to break working TF configs so we're going to have to hold this until TF 0.8. :( I'm adding it to that milestone so we know. I'm also going to hijack the top of your issue to make a note to my future self.

[mitchellh]

We got the fix in, will be part of 0.8 beta 1 this week.

[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.

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