docs: func (s *S3ObjectMetadata) Validate() error {
  	invalidParams := request.ErrInvalidParams{Context: "S3ObjectMetadata"}
  	if s.CacheControl != nil && len(*s.CacheControl) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("CacheControl", 1))
  	}
  	if s.ContentDisposition != nil && len(*s.ContentDisposition) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("ContentDisposition", 1))
  	}
  	if s.ContentEncoding != nil && len(*s.ContentEncoding) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("ContentEncoding", 1))
  	}
  	if s.ContentLanguage != nil && len(*s.ContentLanguage) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("ContentLanguage", 1))
  	}
  	if s.ContentMD5 != nil && len(*s.ContentMD5) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("ContentMD5", 1))
  	}
  	if s.ContentType != nil && len(*s.ContentType) < 1 {
  		invalidParams.Add(request.NewErrParamMinLen("ContentType", 1))
  	}
  
  	if invalidParams.Len() > 0 {
  		return invalidParams
  	}
  	return nil
  }