Can't get redis cache to work with apollo server express - node.js

Question

I'm trying to setup a caching system for my apollo express server, but it seems like the guides I've followed from the official docs: https://www.apollographql.com/docs/apollo-server/performance/caching/#memcachedredis-setup do not appear to work for me.
I can verify that in my resolver for a query that it keeps getting hit by console logging that it is being hit each time instead of only being hit once and then the cache being set
// my resolver definition
const getUserProfile = async (_, args, context, info) => {
info.cacheControl.setCacheHint({ maxAge: 300 });
console.log('MISS, set cache hint') // this console logs every time instead of just once
return context;
};
Here is my code:
server.js
...
const redisClient = require('./cacheClient');
let httpServer;
if (process.env.ENV === 'prod') {
httpServer = httpCreateServer(app);
} else {
httpServer = httpsCreateServer(
{
key: fs.readFileSync('./localhost-key.pem'),
cert: fs.readFileSync('./localhost.pem'),
},
app
);
}
const apolloServer = new ApolloServer({
typeDefs,
resolvers,
cache: new BaseRedisCache({
client: redisClient
}),
cacheControl: true,
});
apolloServer.context = ({ req }) => ({
...
});
await apolloServer.start();
apolloServer.applyMiddleware({ app });
httpServer.listen(PORT, () =>
console.log(`Server is now running on port ${PORT}`)
);
cacheClient.js
require('dotenv').config();
const { REDIS_SERVER, REDIS_PORT } = process.env;
const redis = require('redis');
const client = redis.createClient({
host: REDIS_SERVER,
port: REDIS_PORT,
});
client.on('connect', () => {
console.log('Redis client connected');
});
client.on('message', (channel, message) => {
console.log(`Received ${message} from ${channel}`);
});
module.exports = client;
I'm also making sure my web app is sending a Cache-Control: max-age=300 header on the graphql query as well. I also checked my Redis server and verified that no new keys are added after making the graphql query.
I have also tried setting the cacheControl directive onto the type like:
type UserProfile #cacheControl(maxAge: 300) {
...
}
but no luck with that either. I appreciate any help, thank you!

Answer 1

Whether you use koa or express, you will need to add these plugins: https://www.apollographql.com/docs/apollo-server/api/plugin/cache-control/
https://www.apollographql.com/docs/apollo-server/performance/caching#identifying-users-for-private-responses
...
const responseCachePlugin = require('apollo-server-plugin-response-cache').default;
const { ApolloServerPluginCacheControl } = require("apollo-server-core");
const server = new ApolloServer({
typeDefs,
resolvers,
plugins: [responseCachePlugin({
sessionId: ({ context }) => (context.ctx.header ? context.ctx.header.authorization : null),
}),
ApolloServerPluginCacheControl({
// Cache everything for 1000 seconds.
defaultMaxAge: 1000,
// Don't send the `cache-control` response header.
calculateHttpHeaders: false,
}),
],
});
Important Notes:
Change this code context.ctx.header ? context.ctx.header.authorization to get session Id for specific user.
Make sure that the version of apollo-server-express you use will fire events willResolveField for getting values from the cache and willSendResponse for setting the value in cache when needed (because I had a problem with v2.25.x in Koa).
Using const redis = require('redis'); will not set ttl (maxAge) correctly. So, please make sure to use ioredis instead to be able to set ttl.