langsmith
Version:
Client library to connect to the LangSmith Observability and Evaluation Platform.
36 lines (35 loc) • 1.25 kB
JavaScript
import rng from "./rng.js";
import { unsafeStringify } from "./stringify.js";
function v4(options, buf, offset) {
if (!buf && !options && crypto.randomUUID) {
return crypto.randomUUID();
}
// Putting tail-code that could just go inline here in a separate function to
// enable compiler optimizations that dramatically improve performance.
//
// REF: https://github.com/uuidjs/uuid/issues/892
return _v4(options, buf, offset);
}
function _v4(options, buf, offset) {
options = options || {};
const rnds = options.random ?? options.rng?.() ?? rng();
if (rnds.length < 16) {
throw new Error("Random bytes length must be >= 16");
}
// Per 4.4, set bits for version and `clock_seq_hi_and_reserved`
rnds[6] = (rnds[6] & 0x0f) | 0x40;
rnds[8] = (rnds[8] & 0x3f) | 0x80;
// Copy bytes to buffer, if provided
if (buf) {
offset = offset || 0;
if (offset < 0 || offset + 16 > buf.length) {
throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`);
}
for (let i = 0; i < 16; ++i) {
buf[offset + i] = rnds[i];
}
return buf;
}
return unsafeStringify(rnds);
}
export default v4;