/** * Copyright (c) Meta Platforms, Inc. and affiliates. * * This source code is licensed under the MIT license found in the * LICENSE file in the root directory of this source tree. * * @format * @flow strict */ 'use strict'; const base64 = require('base64-js'); function binaryToBase64(data: ArrayBuffer | $ArrayBufferView): string { if (data instanceof ArrayBuffer) { // $FlowFixMe[reassign-const] data = new Uint8Array(data); } if (data instanceof Uint8Array) { return base64.fromByteArray(data); } if (!ArrayBuffer.isView(data)) { throw new Error('data must be ArrayBuffer or typed array'); } // Already checked that `data` is `DataView` in `ArrayBuffer.isView(data)` const {buffer, byteOffset, byteLength}: DataView = (data: $FlowFixMe); return base64.fromByteArray(new Uint8Array(buffer, byteOffset, byteLength)); } module.exports = binaryToBase64;