langsmith
Version:
Client library to connect to the LangSmith Observability and Evaluation Platform.
89 lines (88 loc) • 3.41 kB
JavaScript
;
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.updateV7State = updateV7State;
const rng_js_1 = __importDefault(require("./rng.cjs"));
const stringify_js_1 = require("./stringify.cjs");
const _state = {};
function v7(options, buf, offset) {
let bytes;
if (options) {
// With options: Make UUID independent of internal state
bytes = v7Bytes(options.random ?? options.rng?.() ?? (0, rng_js_1.default)(), options.msecs, options.seq, buf, offset);
}
else {
// No options: Use internal state
const now = Date.now();
const rnds = (0, rng_js_1.default)();
updateV7State(_state, now, rnds);
bytes = v7Bytes(rnds, _state.msecs, _state.seq, buf, offset);
}
return buf ?? (0, stringify_js_1.unsafeStringify)(bytes);
}
// (Private!) Do not use. This method is only exported for testing purposes
// and may change without notice.
function updateV7State(state, now, rnds) {
state.msecs ??= -Infinity;
state.seq ??= 0;
if (now > state.msecs) {
// Time has moved on! Pick a new random sequence number
state.seq = (rnds[6] << 23) | (rnds[7] << 16) | (rnds[8] << 8) | rnds[9];
state.msecs = now;
}
else {
// Bump sequence counter w/ 32-bit rollover
state.seq = (state.seq + 1) | 0;
// In case of rollover, bump timestamp to preserve monotonicity. This is
// allowed by the RFC and should self-correct as the system clock catches
// up. See https://www.rfc-editor.org/rfc/rfc9562.html#section-6.2-9.4
if (state.seq === 0) {
state.msecs++;
}
}
return state;
}
function v7Bytes(rnds, msecs, seq, buf, offset = 0) {
if (rnds.length < 16) {
throw new Error("Random bytes length must be >= 16");
}
if (!buf) {
buf = new Uint8Array(16);
offset = 0;
}
else {
if (offset < 0 || offset + 16 > buf.length) {
throw new RangeError(`UUID byte range ${offset}:${offset + 15} is out of buffer bounds`);
}
}
// Defaults
msecs ??= Date.now();
seq ??= ((rnds[6] * 0x7f) << 24) | (rnds[7] << 16) | (rnds[8] << 8) | rnds[9];
// byte 0-5: timestamp (48 bits)
buf[offset++] = (msecs / 0x10000000000) & 0xff;
buf[offset++] = (msecs / 0x100000000) & 0xff;
buf[offset++] = (msecs / 0x1000000) & 0xff;
buf[offset++] = (msecs / 0x10000) & 0xff;
buf[offset++] = (msecs / 0x100) & 0xff;
buf[offset++] = msecs & 0xff;
// byte 6: `version` (4 bits) | sequence bits 28-31 (4 bits)
buf[offset++] = 0x70 | ((seq >>> 28) & 0x0f);
// byte 7: sequence bits 20-27 (8 bits)
buf[offset++] = (seq >>> 20) & 0xff;
// byte 8: `variant` (2 bits) | sequence bits 14-19 (6 bits)
buf[offset++] = 0x80 | ((seq >>> 14) & 0x3f);
// byte 9: sequence bits 6-13 (8 bits)
buf[offset++] = (seq >>> 6) & 0xff;
// byte 10: sequence bits 0-5 (6 bits) | random (2 bits)
buf[offset++] = ((seq << 2) & 0xff) | (rnds[10] & 0x03);
// bytes 11-15: random (40 bits)
buf[offset++] = rnds[11];
buf[offset++] = rnds[12];
buf[offset++] = rnds[13];
buf[offset++] = rnds[14];
buf[offset++] = rnds[15];
return buf;
}
exports.default = v7;