Add variable validation for build user case and length

[JM2K69]

Code of Conduct

• I have read and agree to the project's Code of Conduct.

Project Version

develop

VMware vSphere

7.0.3

HashiCorp Packer

1.10.3

HashiCorp Packer Plugin for VMware vSphere

1.26.7

Guest Operating System

Debian 12.5

Environment Details

No response

Description

Error when username start with un Upercase : I use User.

Expected Behavior

the build must continue

Actual Behavior

the build stop

Steps to Reproduce

Use a username for exemple Packer the build will fail with debian 12;5

Log Fragments and Files

No response

Screenshots

Additional Context

No response

[tenthirtyam]

This would likely impact more than just Debian 12. Certainly Debian 11 and other Linux distributions.

[tenthirtyam]

I've updated the issue description to reflect the changes needed.

[JM2K69]

I try this regex validation without success @tenthirtyam

variable "build_username" {
  type        = string
  description = "The username to login to the guest operating system
  validation {
       condition     = can(regex("^[a-z][a-zA-Z0-9_]*", var.build_username))
    error_message = "The username account must start with a letter in lowercase"
  }
 validation {
    condition     = length(var.build_username) > 4 && length(var.build_username) < 8
    error_message = "The username lenght must between 4 and 8 characters"
  }
}

[tenthirtyam]

We have a PR in with a change that will address this requirement when using an updated build script.

[JM2K69]

We have a PR in with a change that will address this requirement when using an updated build script.
Should we close this issue ? And start a new one ?

[tenthirtyam]

Nah, all good. This issue is linked to the PR.