Crypto API Reference

This document provides a concise API reference for the Crypto class and its related interfaces, which provide cryptographic hashing functionality, specifically SHA-256 hashing, with compatibility across Node.js and React Native environments.

Types and Interfaces

HashInput

Input data types supported for hashing.

Values

  • string

  • Buffer

  • Uint8Array

  • ArrayBuffer

CryptoModule

Interface representing a cryptographic module capable of creating hash instances or providing a direct SHA256 method.

Properties

  • createHash? (optional method): Function accepting an algorithm name and returning a Hash instance.

  • SHA256? (optional method): Convenience method accepting HashInput and returning an object with a toString() method to get the hash string.

Hash

Interface representing a hash computation instance.

Methods

  • update(data: HashInput): Hash Updates the hash with the given data. Returns the Hash instance for chaining.

  • digest(encoding: 'hex'): string Finalizes the hash computation and returns the digest in the specified encoding format (only 'hex' supported here).

Class: Crypto

sha256

public static sha256(data: HashInput): string

Computes the SHA-256 hash of the given input data.

Parameters

  • data (required, HashInput): The input data to hash. Supported types include string, Buffer, Uint8Array, and ArrayBuffer.

Returns

  • A hexadecimal string representing the SHA-256 hash of the input data.

Throws

  • Throws an error if no compatible crypto module can be found in the current environment.

Details

  • Internally uses the first available crypto module in the following order:

    1. Node.js built-in crypto module.

    2. react-native-quick-crypto module (for React Native).

  • Converts various input types to a Node.js Buffer before hashing.

Internal Functions (not part of public API)

getAvailableCryptoModule

function getAvailableCryptoModule(): CryptoModule

Selects and returns a compatible cryptographic module available in the runtime environment.

Returns

  • The first compatible CryptoModule found (crypto for Node.js or react-native-quick-crypto for React Native).

Throws

  • Throws an error if no compatible crypto module is found, prompting the user to install required polyfills.

convertInputToBuffer

function convertInputToBuffer(data: HashInput): Buffer

Converts the input data of various supported types into a Node.js Buffer.

Parameters

  • data (required, HashInput): The input data to convert.

Returns

  • A Buffer instance representing the input data in UTF-8 encoding (for strings) or raw bytes (for binary types).

See Also

Crypto Developer Guide