Utils

Utility functions and constants exported by nostr-core.

Import

import {
  normalizeURL,
  bytesToHex,
  hexToBytes,
  randomBytes,
  utf8Encoder,
  utf8Decoder,
} from 'nostr-core'

normalizeURL

function normalizeURL(url: string): string

Normalizes a relay URL for consistent comparison.

Parameter	Type	Description
url	string	Relay URL

Returns: string - normalized WebSocket URL.

Throws: Error with message 'Invalid URL: <url>' if parsing fails.

Normalization rules:

• http:// → ws://, https:// → wss://
• Adds wss:// if no protocol specified
• Removes trailing slashes from pathname
• Removes default ports (80 for ws://, 443 for wss://)
• Sorts query parameters
• Removes URL fragments

normalizeURL('relay.example.com')
// 'wss://relay.example.com'

normalizeURL('https://relay.example.com/')
// 'wss://relay.example.com'

normalizeURL('ws://relay.example.com:80')
// 'ws://relay.example.com'

bytesToHex

function bytesToHex(bytes: Uint8Array): string

Converts a byte array to a hex string.

Parameter	Type	Description
bytes	Uint8Array	Byte array

Returns: string - hex-encoded string.

Re-exported from @noble/hashes/utils.

bytesToHex(new Uint8Array([0xde, 0xad]))
// 'dead'

hexToBytes

function hexToBytes(hex: string): Uint8Array

Converts a hex string to a byte array.

Parameter	Type	Description
hex	string	Hex-encoded string

Returns: Uint8Array

Re-exported from @noble/hashes/utils.

hexToBytes('dead')
// Uint8Array [ 0xde, 0xad ]

randomBytes

function randomBytes(len: number): Uint8Array

Generates cryptographically secure random bytes.

Parameter	Type	Description
len	number	Number of bytes

Returns: Uint8Array

Re-exported from @noble/hashes/utils.

randomBytes(32)
// Uint8Array(32) [ ... ]

utf8Encoder

const utf8Encoder: TextEncoder

Global TextEncoder instance for UTF-8 encoding.

utf8Encoder.encode('Hello')
// Uint8Array [ 72, 101, 108, 108, 111 ]

utf8Decoder

const utf8Decoder: TextDecoder

Global TextDecoder instance for UTF-8 decoding.

utf8Decoder.decode(new Uint8Array([72, 101, 108, 108, 111]))
// 'Hello'