Packer json to hcl conversion with Vault

Packer
1

I transformed my existing packer JSON to an HCL file using the “hcl2_upgrade” command. In the converted HCL file the following lines are added for the Vault variables:

could not parse template for following block: “template: hcl2_upgrade:4: function “vault” not defined”

variable “vcenter_admin” {
type = string
default = “{{vault kv/packer/ vc_username}}”
}

When run a packer build I’ve got the following error:

Error: render ‘password’: template: root:1:2: executing “root” at <vault kv/packer vc_password>: error calling vault: Vault vars are only allowed in the variables section in:

{{vault kv/packer vc_password}}

on w10-20h2.pkr.hcl line 125:
(source code not available)

Q: What do I need to change in my HCL file to make the Vault integration getting working again?

2

Does anyone have a suggestion?

3

I believe you need to use locals instead of input variables:

4

Thanks. Using locals did the trick.

5

As an addition, for people bumping into this issue after converting from json to hcl, that’s also because the syntax of the vault function is different between them, for example:

JSON: "{{ vault /infra/vsphere/data/packer password}}"
HCL: vault("/infra/vsphere/data/packer", "password")

As depicted here: vault - Functions - Configuration Language | Packer | HashiCorp Developer

The error log is a bit confusing, as it only say that we should use Vault in the variables section, and the only answer I could find is this one, hence my little addition to the original answer :slight_smile: