hashicorp/packer · error

Plugin source has a type with the prefix

Error message

Plugin source has a type with the prefix %q, which isn't valid.
Although that prefix is often used in the names of version control repositories for Packer plugins, plugin source strings should not include it.

Did you mean %q?

What it means

Packer detects the common mistake of including the 'packer-plugin-' prefix in a source address's type segment. When stripping that prefix yields a valid type, it returns this helpful suggestion error pointing at the corrected source. The check is guarded so the suggestion is only shown when it would itself be valid.

Solutions

1. Drop the 'packer-plugin-' prefix from the type segment, as the suggested form in the message shows
2. Use only the plugin type name, e.g. 'github.com/hashicorp/amazon'
3. Verify with 'packer init' after the edit

Example fix

// before
source = "github.com/hashicorp/packer-plugin-amazon"
// after
source = "github.com/hashicorp/amazon"

name := src[strings.LastIndex(src, "/")+1:]
if strings.HasPrefix(name, "packer-plugin-") { /* strip prefix before installing */ }

func hasPackPluginPrefix(s string) bool { return strings.Contains(s, "/packer-plugin-") }

When it happens

Trigger: ParsePluginSourceString given e.g. 'github.com/hashicorp/packer-plugin-amazon' where the type segment starts with the 'packer-plugin-' user-error prefix.

Common situations: Users naming the source after the git repository ('packer-plugin-docker') instead of the plugin type; copying repo URLs directly into required_plugins.

Related errors

• The provided source URL is invalid. The following errors…
• cannot use multiple consecutive dashes
• Invalid plugin type in source
• must contain only letters, digits, and dashes, and may not…
• Plugin source has a type with the

AI-assisted analysis of hashicorp/packer@eb36e3c3e4 (2026-09-05). Data as JSON: /api/errors/31b6b1094881b656. Report an issue: GitHub.

Appendix: source

Thrown at hcl2template/addrs/plugin.go:185

	// so we've made that invalid from the start both so we can give feedback
	// to plugin developers about the packer- prefix being redundant
	// and give specialized feedback to folks who incorrectly use the full
	// packer-plugin- prefix to help them self-correct.
	const redundantPrefix = "packer-"
	const userErrorPrefix = "packer-plugin-"
	if strings.HasPrefix(givenName, redundantPrefix) {
		if strings.HasPrefix(givenName, userErrorPrefix) {
			// Likely user error. We only return this specialized error if
			// whatever is after the prefix would otherwise be a
			// syntactically-valid plugin type, so we don't end up advising
			// the user to try something that would be invalid for another
			// reason anyway.
			// (This is mainly just for robustness, because the validation
			// we already did above should've rejected most/all ways for
			// the suggestedType to end up invalid here.)
			suggestedType := strings.Replace(givenName, userErrorPrefix, "", -1)
			if _, err := ParsePluginPart(suggestedType); err == nil {
				return nil, fmt.Errorf("Plugin source has a type with the prefix %q, which isn't valid.\n"+
					"Although that prefix is often used in the names of version control repositories "+
					"for Packer plugins, plugin source strings should not include it.\n"+
					"\nDid you mean %q?", userErrorPrefix, suggestedType)
			}
		}
		// Otherwise, probably instead an incorrectly-named plugin, perhaps
		// arising from a similar instinct to what causes there to be
		// thousands of Python packages on PyPI with "python-"-prefixed
		// names.
		return nil, fmt.Errorf("Plugin source has a type with the %q prefix, which isn't valid.\n"+
			"If you are the author of this plugin, rename it to not include the prefix.\n"+
			"Ex: %q",
			redundantPrefix,
			strings.Replace(givenName, redundantPrefix, "", 1))
	}

	plug := &Plugin{
		Source: str,

View on GitHub (pinned to eb36e3c3e4)