Files
deepseek-harness/packages/util/crypto/src/index.ts
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TypeScript

/**
* UUID minting that works in every JavaScript context this repository ships
* to. `crypto.randomUUID` is a secure-context Web API — a page or worker
* served over plain HTTP on a LAN address has no such method — while
* `crypto.getRandomValues` is unrestricted everywhere (browsers, workers,
* Node ≥ 19). One implementation here replaces per-caller polyfills; the
* `no-restricted-properties` lint rule points `crypto.randomUUID` callers at
* this module.
* @module @deepseek-ai/dsh-util-crypto
*/
/** RFC 9562 UUID string, the shape `crypto.randomUUID` declares. */
export type Uuid = `${string}-${string}-${string}-${string}-${string}`
/**
* Encode bytes as canonical base64 without overflowing function argument limits.
* @param data - Bytes to encode.
* @returns base64 text.
*/
export function bytesToBase64(data: Uint8Array): string {
let binary = ''
const chunk = 0x8000
for (let offset = 0; offset < data.length; offset += chunk) {
binary += String.fromCharCode(...data.subarray(offset, offset + chunk))
}
return btoa(binary)
}
/**
* Random v4 UUID, minted from `crypto.getRandomValues`.
* @returns the UUID string.
*/
export function randomUUID(): Uuid {
const bytes = globalThis.crypto.getRandomValues(new Uint8Array(16))
// RFC 9562 §5.4: version 4 in the high nibble of byte 6, variant 10 in byte 8.
const hex = Array.from(bytes, (byte, index) => {
const pinned = index === 6 ? (byte & 0x0f) | 0x40 : index === 8 ? (byte & 0x3f) | 0x80 : byte
return pinned.toString(16).padStart(2, '0')
}).join('')
return `${hex.slice(0, 8)}-${hex.slice(8, 12)}-${hex.slice(12, 16)}-${hex.slice(16, 20)}-${hex.slice(20)}`
}