add possibility to use variables everywhere in post-processor blocks

[azr]

Todo list:

• feature
• tests

Including in:

• name
• only
• except
• keep_input_artifact

Example file:

source "null" "example1" {
  communicator = "none"
}

source "null" "example2" {
  communicator = "none"
}

locals {
  except = "null.example1"
}

variable "only" {
  default = "null.example1"
}

build {
  sources = ["source.null.example1", "source.null.example2"]
  post-processor "shell-local" {
    except = [local.except]
    inline = ["echo first post-processor"]
  }

  post-processor "shell-local" {
    only   = [var.only]
    inline = ["echo second post-processor"]
  }
}

Ouput:

$ packer build foo.pkr.hcl
null.example1: output will be in this color.
null.example2: output will be in this color.

==> null.example1: Running post-processor:  (type shell-local)
==> null.example2: Running post-processor:  (type shell-local)
==> null.example2 (shell-local): Running local shell script: /var/folders/3k/2gb5ct4s7cncr52_jh2kz6cw0000gq/T/packer-shell201696062
==> null.example1 (shell-local): Running local shell script: /var/folders/3k/2gb5ct4s7cncr52_jh2kz6cw0000gq/T/packer-shell494781572
    null.example1 (shell-local): second post-processor
Build 'null.example1' finished after 61 milliseconds 432 microseconds.
    null.example2 (shell-local): first post-processor
Build 'null.example2' finished after 111 milliseconds 678 microseconds.

==> Wait completed after 111 milliseconds 714 microseconds

close #4895

[sylviamoss]

Nice!! Indeed super simple! 👍🏼

[vishalbasra]

super awesome!
thankyou so much, I'll be testing this out shortly!

[github-actions]

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