gohugoio/hugo · error

resource %q of media type %q does not support this method: %

Error message

resource %q of media type %q does not support this method: %s

What it means

Thrown by resourceAdapter.getImageOps() (transform.go:401-415) when the underlying target does not implement images.ImageResourceOps, i.e. the resource is not a processable image. The panic includes the resource name, media type, and explicit instructions to check support with reflect.IsImageResource / IsImageResourceProcessable / IsImageResourceWithMeta before calling image methods.

Source

Thrown at resources/transform.go:414

func (r resourceAdapter) WithResourceMeta(mp resource.ResourceMetaProvider) resource.Resource {
	r.metaProvider = mp
	return &r
}

func (r *resourceAdapter) getImageOps() images.ImageResourceOps {
	img, ok := r.target.(images.ImageResourceOps)
	if !ok {
		instructions := "use reflect.IsImageResource, " +
			"reflect.IsImageResourceProcessable, or " +
			"reflect.IsImageResourceWithMeta to check if the resource " +
			"supports this method before calling it"
		msg := fmt.Sprintf(
			"resource %q of media type %q does not support this method: %s",
			r.Name(),
			r.MediaType(),
			instructions,
		)
		panic(msg)
	}
	r.init(false, false)

	return img
}

// ResolveImageOpsSupport reports the ImageOpsSupport for the given resource. This can be used to determine if a resource supports image operations like Resize, Crop, etc.
func ResolveImageOpsSupport(v any) images.ImageResourceType {
	r, ok := v.(resource.Resource)
	if !ok {
		return images.ImageResourceTypeNone
	}
	mt := r.MediaType()
	if mt.MainType != "image" {
		return images.ImageResourceTypeNone
	}
	_, support := images.ImageFormatFromMediaSubType(mt.SubType)
	return support

View on GitHub (pinned to 52c9bd7908)

Solutions

1. Use reflect.IsImageResource / IsImageResourceProcessable to guard before calling image methods.
2. Confirm the resource's MediaType is an image subtype Hugo can process (jpeg/png/gif/webp/tiff/bmp).
3. Note SVG is generally not raster-processable; convert or handle separately.

Example fix

// before
{{ $img := $r.Resize "100x100" }}
// after
{{ if reflect.IsImageResourceProcessable $r }}
  {{ $img := $r.Resize "100x100" }}
{{ end }}

{{ if reflect.IsImageResourceProcessable $r }}
  {{ $img := $r.Resize "100x100" }}
{{ else }}
  {{ errorf "resource %s is not a processable image" $r.Name }}
{{ end }}

// IsProcessableImage reports whether r supports image operations.
func IsProcessableImage(r resource.Resource) bool {
    return images.ResolveImageOpsSupport(r) != images.ImageResourceTypeNone
}

When it happens

Trigger: Calling an image method (Resize, Crop, Fit, Fill, Filter/Process, DecodeImage, etc.) on a resource whose media type is not an image, or whose subtype is not a supported image format. The method dispatch happens lazily inside getImageOps.

Common situations: A page bundles a PDF or SVG expecting Resize to work; a non-image resource is passed through a generic image-processing partial; or the media type is misconfigured (e.g. wrong MIME for a WebP).

Related errors

• no Resource provided in transformation
• no Key set in Resource
• failed to resolve media type for suffix %q
• failed to resolve media type for %q
• media type %q not found

AI-assisted analysis of gohugoio/hugo@52c9bd7908 (2026-08-09). Data as JSON: /api/errors/cace3870082e7c7a. Report an issue: GitHub.