Medplum

// SPDX-FileCopyrightText: Copyright Orangebot, Inc. and Medplum contributors // SPDX-License-Identifier: Apache-2.0 import { getBuffer, isBrowserEnvironment } from './environment'; /** * Decodes a base64 string. * Handles both browser and Node environments. * Supports Unicode characters. * @param data - The base-64 encoded input string. * @returns The decoded string. */ export function decodeBase64(data: string): string { if (isBrowserEnvironment()) { const binaryString = window.atob(data); const bytes = Uint8Array.from(binaryString, (c) => c.codePointAt(0) as number); return new window.TextDecoder().decode(bytes); } const BufferConstructor = getBuffer(); if (BufferConstructor) { return BufferConstructor.from(data, 'base64').toString('utf-8'); } throw new Error('Unable to decode base64'); } /** * Encodes a base64 string. * Handles both browser and Node environments. * Supports Unicode characters. * @param data - The unencoded input string. * @returns The base-64 encoded string. */ export function encodeBase64(data: string): string { if (isBrowserEnvironment()) { const utf8Bytes = new window.TextEncoder().encode(data); // utf8Bytes is a Uint8Array, but String.fromCodePoint expects a sequence of numbers. const binaryString = String.fromCodePoint.apply(null, utf8Bytes as unknown as number[]); return window.btoa(binaryString); } const BufferConstructor = getBuffer(); if (BufferConstructor) { return BufferConstructor.from(data, 'utf8').toString('base64'); } throw new Error('Unable to encode base64'); } /** * Encodes a string into Base64URL format. * This is the encoding required for JWT parts. * @param data - The unencoded input string. * @returns The Base64URL encoded string. */ export function encodeBase64Url(data: string): string { return encodeBase64(data) .replaceAll('+', '-') // Replace + with - .replaceAll('/', '_') // Replace / with _ .replace(/[=]{1,2}$/, ''); // Remove trailing = } /** * Decodes a string from Base64URL format. * @param data - The Base64URL encoded input string. * @returns The decoded string. */ export function decodeBase64Url(data: string): string { data = data.padEnd(data.length + ((4 - (data.length % 4)) % 4), '='); const base64 = data.replaceAll('-', '+').replaceAll('_', '/'); return decodeBase64(base64); }