Welcome to TroveQL!

TroveQL is a cache library for GraphQL APIs on Express.js servers with additional support for TroveMetrics, a cache performance monitoring application.


  • Server-side cache for GraphQL queries using the Advanced Replacement Cache (ARC) algorithm
  • Custom cache configurations with options such as total capacity
  • Cache invalidation logic on GraphQL mutations
  • Support for Node.js/Express.js servers
  • Cache performance monitoring with key metrics such as Hit/Miss Rate and Query Response Time


Visit our website to get more information and watch a demo of TroveQL and its performance monitoring application TroveMetrics.

Install TroveQL

Install the Express library via npm

npm install troveql

Set up TroveQL in Express

  1. Import TroveQLCache
const { TroveQLCache } = require('troveql');
  1. Set up your TroveQL cache

const capacity = 5; // size limit of your cache
const graphQLAPI = 'http://localhost:4000/graphql'; // your graphQL URL endpoint
const useTroveMetrics = true; // (optional) if you would like to use TroveMetrics - default is false
const mutations = {}; // (optional) object where key/value pairs are mutation types/object types mutated (ex. { addMovie: 'movie', editMovie: 'movie', deleteMovie: 'movie' })
const cache = new TroveQLCache(capacity, graphQLAPI, useTroveMetrics, mutations);
  1. Add the /troveql and, if applicable, /trovemetrics endpoints

app.use(express.urlencoded({ extended: true }));

// /troveql to use the cache
  (req: Request, res: Response) => res.status(200).json(res.locals.value)

// /trovemetrics to clear the cache from TroveMetrics
  (req: Request, res: Response) => res.status(200).json(res.locals.message)
  1. Add your GraphQL endpoint. For example:

const { graphqlHTTP } = require("express-graphql");
const { schema } = require('./schema');
const { resolvers } = require('./resolvers');

    schema: schema, 
    rootValue: resolvers,
    graphiql: true
  1. To use TroveMetrics to monitor the performance of your cache and GraphQL API on your application’s server, you can go to our website and download the desktop application for your OS (macOS, Windows, Linux).

Query or Mutate your GraphQL API

Simply send a request to your GraphQL API for queries and mutations as you normally would. For example, a query with variables using the fetch syntax could look like:

fetch('/troveql', {
  method: 'POST',
  headers: { 
    'Content-Type': 'application/json' 
  body: JSON.stringify({
    query: `query ($id: ID) {
      movie(id: $id) {
    variables: { id: 10 }
.then(response => response.json())
.then(response => {
  // access the data on the response object with response.data

TroveQL Demo

Download our TroveQL demo to see how TroveQL is run: troveql-demo

Feature Roadmap

  • Client-side caching
  • Persistent queries to improve the performance and security of client queries to the server
  • Additional cache invalidation logic on mutations
  • Additional cache logic on subscriptions
  • Update cache capacity to reflect memory size (bytes) instead of number of items
  • User authentication for TroveMetrics

Contribution Guidelines

If you would like to contribute to this open-source project, please follow the steps below:

  1. Fork the repository from the dev branch
  2. Create a new feature branch (git checkout -b feature/newFeature)
  3. Commit your changes with a descriptive comment (git commit -m 'Added a new feature that ...')
  4. Push your changes to the new feature branch (git push origin feature/newFeature)
  5. Open a Pull Request on the dev branch
  6. We will review your PR and merge the new feature into the main branch as soon as possible!

Thank you so much!


  • GraphQL
  • Node.js / Express.js
  • Electron
  • React.js
  • Chart.js
  • Webpack
  • TypeScript
  • JavaScript
  • HTML
  • CSS / SASS
  • Jest


Alex Klein – GitHub | LinkedIn

Erika Jung – GitHub | LinkedIn

Sam Henderson – GitHub | LinkedIn

Tricia Yeh – GitHub | LinkedIn


This project is licensed under the MIT License.


View Github