func (a *API) FetchAnnotation(cid CIDType) (*Annotation, error) {
	if cid == nil || *cid == "" {
		return nil, fmt.Errorf("Invalid annotation CID [none]")
	}

	annotationCID := string(*cid)

	matched, err := regexp.MatchString(config.AnnotationCIDRegex, annotationCID)
	if err != nil {
		return nil, err
	}
	if !matched {
		return nil, fmt.Errorf("Invalid annotation CID [%s]", annotationCID)
	}

	result, err := a.Get(annotationCID)
	if err != nil {
		return nil, err
	}

	if a.Debug {
		a.Log.Printf("[DEBUG] fetch annotation, received JSON: %s", string(result))
	}

	annotation := &Annotation{}
	if err := json.Unmarshal(result, annotation); err != nil {
		return nil, err
	}

	return annotation, nil
}
func (a *API) FetchAnnotation(cid CIDType) (*Annotation, error) {
	if cid == nil || *cid == "" {
		return nil, fmt.Errorf("Invalid annotation CID [none]")
	}

	annotationCID := string(*cid)

	matched, err := regexp.MatchString(config.AnnotationCIDRegex, annotationCID)
	if err != nil {
		return nil, err
	}
	if !matched {
		return nil, fmt.Errorf("Invalid annotation CID [%s]", annotationCID)
	}

	result, err := a.Get(annotationCID)
	if err != nil {
		return nil, err
	}

	if a.Debug {
		a.Log.Printf("[DEBUG] fetch annotation, received JSON: %s", string(result))
	}

	annotation := &Annotation{}
	if err := json.Unmarshal(result, annotation); err != nil {
		return nil, err
	}

	return annotation, nil
}
// FetchAnnotation retrieves annotation with passed cid.