Add disk and config support

[zliang-akamai]

📝 Description

Resolve #222

Add support for custom disks and configuration profiles in the Linode builder, enabling advanced provisioning with custom disk layouts, multiple filesystems, and configuration profiles instead of pre-built images.

Changes

• New Config Structs: Added Disk, InstanceConfig, InstanceConfigDevices, InstanceConfigDevice, and InstanceConfigHelpers structs with full HCL2 support
• Build Step: Implemented step_create_disk_config.go for custom disk creation, label resolution, and configuration profile management
• Validation: Enhanced Prepare() method with comprehensive checks preventing incompatible configurations
• Documentation: Updated builder docs with examples and field references
• Tests: Added 12 unit tests and 3 acceptance tests covering all scenarios
• Architecture: Two-mode support (standard vs custom) with backwards compatibility

✔️ How to Test

Auto Testing

make unit-test

make int-test

Manual Testing

Save this into a file maybe named as test.pkr.hcl. Then checkout this branch and make dev to install it. Run packer build . to test it.

locals { timestamp = regex_replace(timestamp(), "[- TZ:]", "") }

source "linode" "example" {
  image_description = "My Private Image"
  image_label       = "private-image-${local.timestamp}"
  instance_label    = "temporary-linode-${local.timestamp}"
  instance_type     = "g6-nanode-1"
  region            = "us-mia"
  ssh_username      = "root"
  interface_generation = "linode"

  linode_interface {
    public {
      ipv4 {
        address {
          address = "auto"
          primary = true
        }
      }
    }
  }

  config {
    label       = "my-config"
    comments    = "Boot config"
    kernel      = "linode/latest-64bit"
    root_device = "/dev/sda"
    run_level   = "default"
    
    devices {
      sda { disk_label = "boot" }
    }
    
    helpers {
      updatedb_disabled   = true
      distro              = true
      modules_dep         = true
      network             = true
      devtmpfs_automount  = true
    }
  }

  disk {
    label           = "boot"
    size            = 25000
    image           = "linode/ubuntu24.04"
  }
}

build {
  sources = ["source.linode.example"]
}

[Copilot]

Pull request overview

Adds support for advanced Linode provisioning by allowing custom disk layouts and configuration profiles (instead of relying solely on a pre-built image).

Changes:

• Introduces new disk and config configuration blocks (HCL2 support + validation updates).
• Adds a new build step to create disks/config profiles and boot via a selected config.
• Updates docs/examples and expands unit/acceptance tests around the new configuration mode.

Reviewed changes

Copilot reviewed 16 out of 16 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
go.mod	Updates Go language version used by the module.
builder/linode/config.go	Adds new configuration structs and updates validation to support custom disk/config mode.
builder/linode/config.hcl2spec.go	Adds generated HCL2 spec support for new disk and config blocks.
builder/linode/step_create_linode.go	Adjusts instance creation to omit image/boot when provisioning disks/configs explicitly.
builder/linode/step_create_disk_config.go	Implements custom disk creation, config profile creation, and manual boot.
builder/linode/builder.go	Inserts the new disk/config creation step into the build pipeline.
builder/linode/builder_test.go	Adds unit tests for new validation and parsing behavior.
builder/linode/builder_acc_test.go	Adds acceptance tests for custom disks/configs and interface combinations.
docs/builders/linode.mdx	Documents custom disk/config usage and adds full examples.
.web-docs/components/builder/linode/README.md	Mirrors docs updates in generated web docs.
example/*	Updates example templates (regions/images) to newer defaults.
builder/linode/artifact_test.go	Updates expected source image metadata in tests.
AGENTS.md	Adds repository guidelines for AI coding agents.

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Pull request overview

Copilot reviewed 19 out of 19 changed files in this pull request and generated 11 comments.

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Pull request overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 4 comments.

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Pull request overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull request overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 4 comments.

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[Copilot]

Pull request overview

Copilot reviewed 21 out of 21 changed files in this pull request and generated 7 comments.

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