What causes "No files specified in artifice configuration" in hashicorp/packer?

Add the intended file paths to the artifice `files` attribute

No files specified in artifice configuration

Error message

No files specified in artifice configuration

What it means

Configuration-time validation for the artifice post-processor: it refuses to configure when the required `files` list is empty. Artifice's whole purpose is to extract specific files from the builder's output, so an empty list makes the post-processor meaningless and is rejected up front.

Source

Thrown at post-processor/artifice/post-processor.go:55

}

func (p *PostProcessor) ConfigSpec() hcldec.ObjectSpec { return p.config.FlatMapstructure().HCL2Spec() }

func (p *PostProcessor) Configure(raws ...interface{}) error {
	err := config.Decode(&p.config, &config.DecodeOpts{
		PluginType:         "artifice",
		Interpolate:        true,
		InterpolateContext: &p.config.ctx,
		InterpolateFilter: &interpolate.RenderFilter{
			Exclude: []string{},
		},
	}, raws...)
	if err != nil {
		return err
	}

	if len(p.config.Files) == 0 {
		return fmt.Errorf("No files specified in artifice configuration")
	}

	return nil
}

func (p *PostProcessor) PostProcess(ctx context.Context, ui packersdk.Ui, artifact packersdk.Artifact) (packersdk.Artifact, bool, bool, error) {
	if len(artifact.Files()) > 0 {
		ui.Say(fmt.Sprintf("Discarding files from artifact: %s", strings.Join(artifact.Files(), ", ")))
	}

	artifact, err := NewArtifact(p.config.Files)
	ui.Say(fmt.Sprintf("Using these artifact files: %s", strings.Join(artifact.Files(), ", ")))

	return artifact, true, false, err
}

View on GitHub (pinned to eb36e3c3e4)

Solutions

Add the intended file paths to the artifice `files` attribute
Confirm the attribute is spelled `files` and is not shadowed/overridden to empty by variables or overrides
Check the merged result (e.g. packer validate) to ensure variable interpolation doesn't yield an empty list

Example fix

// before
post-processor "artifice" {
  files = []
}
// after
post-processor "artifice" {
  files = ["output/result.tar.gz"]
}

Defensive patterns

Strategy: validation

Validate before calling

# HCL2: assert the files list is non-empty before running
locals {
  artifice_files = ["output/result.tar.gz"]
}
# packer validate will surface the artifice error; guard in CI:
# test ${#ARTIFICE_FILES[@]} -gt 0

Try / catch

if err := pp.Configure(raws); err != nil {
    if strings.Contains(err.Error(), "No files specified in artifice configuration") {
        // fix template: add files = [...] to the artifice block
    }
    return err
}

Prevention

Always populate `files` when using the artifice post-processor
Run packer validate before every build to catch empty config early
Avoid variable interpolation that can expand to an empty list
Check for attribute typos (files vs file) when copying templates

When it happens

Trigger: Configuring post-processor "artifice" with no `files` entries, e.g. an HCL2 post-processor block with files = [] or omitted entirely, or a JSON template with "files": [] — Configure() sees len(p.config.Files) == 0 and returns this error before any build runs.

Common situations: Copy-pasting an artifice block and forgetting to fill in files; templating that expands to an empty list; HCL attribute commented out or mistyped (e.g. `file` instead of `files`).

Understand the failure class

Background: "X is required", "must be set", "cannot be empty": the missing-required-config error family, from Vertex AI project/location to WeChat keys — this error's family across 18 libraries.

Related errors

AI-assisted analysis of hashicorp/packer@eb36e3c3e4 (2026-09-05). Data as JSON: /api/errors/17abe6feace6c5d3. Report an issue: GitHub.