errAPI.Description = fmt.Sprintf("%s '(%s)'", errAPI.Description, err)
			writeErrorResponse(ctx, w, errAPI, r.URL)
			return
		}

		// Make sure formValues adhere to policy restrictions.
		if err = checkPostPolicy(formValues, postPolicyForm); err != nil {
			writeErrorResponse(ctx, w, errorCodes.ToAPIErrWithErr(ErrAccessDenied, err), r.URL)
			return
		}