Unvault

Unvault is a minimal layer for node that allows results of time-consuming tasks to be stored. Improved performance is achieved by adding trackers that periodically update the layer, so that stored responses can be served instantly once requested. Also available as middleware.

Features:

Insert key based trackers
Automatic and manual update
Support for async and await
Fast (without dependencies)
Small wrapper extending Map
Support for multiple stores

Install

$ npm install --save unvault

Note: Node 7.6.0 is required for async and await!

Usage

const unvault = require("unvault");

const store = unvault();

store.insert("random", 1000, () => Math.random());

const { value } = store.get("random");

TypeScript

import * as unvault from "unvault";

const store: Unvault = unvault();

Manual

Periodic updates might not suit your application's needs. Unvault supports a manual mode that provides more control over which trackers receive an update and when. Trackers with an interval of 0 will only run once. Both automatic and manual trackers allow for an update trigger.

store.insert("random", 0, () => Math.random());

store.trigger("random");

Advanced

Unvault can be combined with a node servers like Polka or Express to quickly deliver stored content to users. Trackers also work with async and await for asynchronous updates. Store your external fetch responses, database results and other in the vault for faster response times.

const polka = require("polka");
const unvault = require("unvault");
const fetch = require("node-fetch");

const server = polka();
server.listen(3000);

const route = "/api/fetch";
const routes = unvault();

routes.insert(route, 2000, async () => {
  const response = await fetch(
    "https://api.github.com/repos/vaneenige/unvault"
  );
  return response.json();
});

server.get(route, (req, res) => {
  const { value } = routes.get(route);
  server.send(res, 200, value, "application/json");
});

API

.insert(key, interval, update, options)

Inserts a tracker into the vault.

Returns: Result of update function (use await for async updates).

.trigger(key)

Manually runs a tracker.

Returns: Result of update function (use await for async updates).

.prototype

As unvault extends Map, all of its functions are available: clear(), delete(key), entries() and more!

Note: The update callback will receive the key as a parameter. Providing a lifetime variable (in ms) to the options object will delete the tracker and stop its automatic updates once it runs out.

Benchmarks

For this benchmark an example route is setup that searches a mongodb collection that contains 100 nodes. The node server is started with node v9.0.0 and results are documented after a single warm-up run.

The benchmarking tool for results is the following:

$ wrk -t8 -c100 -d10s http://localhost:3000/:type/mongo

Without unvault

Thread Stats   Avg      Stdev     Max   +/- Stdev
  Latency    44.23ms    8.44ms  80.36ms   65.70%
  Req/Sec   271.83     26.52   353.00     64.25%
21755 requests in 10.07s, 209.77MB read

Requests/sec:   2160.05
Transfer/sec:     20.83MB

With unvault

Thread Stats   Avg      Stdev     Max   +/- Stdev
  Latency     4.89ms  391.21us   9.38ms   92.94%
  Req/Sec     2.47k   341.17     9.22k    99.75%
196758 requests in 10.10s, 1.85GB read

Requests/sec:  19481.54
Transfer/sec:    187.85MB

Note: Unvault aims to reduce the time spend creating a response. If the process normally takes a second to finish this solution will eliminate most of that second.

vaneenige/unvault