oslabs-beta / Olympus

A hybrid caching library for GraphQL written for Javascript Express

Welcome to Olympus Caching!

Olympus is a hybrid caching library for GraphQL written for Javascript Express

Features

• Automatically creates and caches GraphQL queries.
• Integrates with any server running on Express/Node.js.
• Includes caching with Redis and in the browser's local storage.

Check out our demo site to see what Olympus can do.

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Table of Contents

• Install
• Server Setup
• Making Queries (Client-side)
• Making Mutations (Client-side)
• The Team
• License

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Install Olympus

Install our Express library via npm

npm install olympus-cache

Set up your Express server

1. Import our Redis Middleware

const RedisCache = require('olympus-server');

2. Set up your Redis Server

const redis = require('redis');
const redisClient = redis.createClient({
    host: "localhost",
    port: 6379,
  });
redisClient.connect();
const redisInstance = new RedisCache(redisClient, '//insert url with /graphql endpoint here');

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

3. Add the following endpoints

app.use('/olympus', redisInstance.cacheResponse, (req, res) => {
    res.status(200).send(res.locals)
});
app.use('/graphql', graphqlHTTP({schema, graphiql: true}));

4. Don't forget to run the command line 'redis-server' on the machine with your server

Making Queries

1. Import Olympus in files that make GraphQL queries

import { Olympus } from 'olympus-fetch';

2. Olympus is designed to make it easy to switch over from the Fetch API. All you have to do is replace the word fetch with the word Olympus. Remove the endpoint argument, and adjust the 'body' key inside the second arugment.

For example, here's how you might send a GraphQL request using the Fetch API:

fetch('/graphql', {
  method: 'POST',
  headers: { 'Content-Type': 'application/graphql' },
  body: // query string
})
.then(/* code */)

And here's what that same request looks like using Olympus:

Olympus({
  method: 'POST',
  headers: { 'Content-Type': 'application/graphql' },
  body: JSON.stringify({query: // query string})
})
.then(/* code */)

Simply replace fetch with Olympus wherever the client-side code queries the GraphQL API, and you're done! You've set up caching inside your client's browser Local Storage.

Making Mutations

In order to make a mutation, follow the same steps above. Simply replace fetch with Olympus wherever the client-side code makes mutations using the GraphQL API, and you're done! Simply enter your string containing the mutation inside of the key "query".

Olympus({
  method: 'POST',
  headers: { 'Content-Type': 'application/graphql' },
  body: JSON.stringify({query: // mutation string})
})
.then(/* code */)

The Team

Adam Lang | GitHub | LinkedIn
Bryan Kim | GitHub | LinkedIn
Kevin Le | GitHub | LinkedIn
Marshall Kim | GitHub | LinkedIn

License

This product is licensed under the MIT License - see the LICENSE file for details.

This is an open source product.

This product is accelerated by OS Labs.