Add cloud init support

[jbriard]

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Description

Add the option of sending data in the “user_data_file” to be able to run cloud init scripts during deployment.

Use Case(s)

The use case is to simplify the deployement and use a more powerfull tool to customize the VM

Potential configuration

  "builders": [
    {
      "project_id": "{{ user `project_id` }}",
      "access_key": "{{ user `access_key` }}",
      "secret_key": "{{ user `secret_key` }}",
      "server_name": "server",
      "image_name": "server-apache",
      "snapshot_name": "server-apache-snapshot",
      "type": "scaleway",
(..)
       "user_data_file": "/path/to/cloud-init-config.yaml"

    }
  ],

Potential References

[gaetan-craft]

You an use user_data in the source definition like

locals {
   cloud-init_scaleway=file("my_file.yml")
}
source "scaleway" "app" { # trufflehog:ignore
  project_id      = "xxxxxxxxxxxxxxxxx"
  image           = data.external.base_scaleway.result.id
  zone            = "fr-par-2"
  commercial_type = "DEV1-M"
  ssh_username    = "ubuntu"
  user_data       = { cloud-init = local.cloud-init_scaleway }
  remove_volume   = true

  tags = [for k, v in local.tags : "${k}:${v}"]

  image_name = local.tags.Name

}

[remyleone]

It would be really helpful to add an example with cloud init to the documentation.