Koa Session access store client connection from context

Question

I'm using nodejs with koa as framework, plus koa-session and koa-redis.

import Koa from 'koa';
...
import session from 'koa-session';
import redisStore from 'koa-redis';

const app = new Koa();
app.keys = ["cookieKeys"];
app.use(session({
  maxAge: 5184000000,
  store: redisStore({url: 'redis://localhost:6379'})
}, app));

...
const server = app.listen(1339, () => {
  console.log(`Server listening on port: 1339`);
});

export default server;

Now it's possible to set ctx.session.key = "value"; and get ctx.sessios.key; on redis, because the connection is already estabelished.

How i can access the same redis client used on the koa-session store in other module? Right now I'm creating a new connection:

import { Context, Next, Middleware } from 'koa';
import redis from 'koa-redis';

export default async (ctx: Context, next: Next): Promise<Middleware> => {
    try {
        return await next();
    } catch (err) {
        if (err.status !== 401) {
            throw err;
        }
        const redisClient = await redis({url: 'redis://localhost:6379'}).client;
        const tokenAccess = ctx.cookies.get('tokenAccess', {signed: true});
        const tokenRefresh = ctx.session.tokenRefresh;
        ...

        const isRefreshTokenRevoked = Number.isInteger(await redisClient.zrank('blacklist', tokenRefresh));
        await redisClient.quit();
        if (isRefreshTokenRevoked) {
            throw err;
        }
        ...
    }
}

I found this property inside context ctx.session._sessCtx.store.client. Is correct to use this property for that purpose?

Answer 1

I guess my question jumped a few steps. I re-writed the code with a db.js file and put my redis connection as a singleton:

import { redisURI } from './config';
import Redis from 'koa-redis';

export const redisStore = Redis({url: redisURI});

So now I could import this connection and use on index.js and other files:

import Koa from 'koa';
...
import session from 'koa-session';
import { redisStore } from './db';
//import redisStore from 'koa-redis';

const app = new Koa();
app.keys = ["cookieKeys"];
app.use(session({
  maxAge: 5184000000,
  store: redisStore
//store: redisStore({url: 'redis://localhost:6379'})
}, app));

...
const server = app.listen(1339, () => {
  console.log(`Server listening on port: 1339`);
});

export default server;

Imported on another module:

import { Context, Next, Middleware } from 'koa';
import { redisStore } from './db';

export default async (ctx: Context, next: Next): Promise<Middleware> => {
    try {
        return await next();
    } catch (err) {
        if (err.status !== 401) {
            throw err;
        }
        //const redisClient = await redis({url: 'redis://localhost:6379'}).client;
        const tokenAccess = ctx.cookies.get('tokenAccess', {signed: true});
        const tokenRefresh = ctx.session.tokenRefresh;
        ...
        const isRefreshTokenRevoked = Number.isInteger(await redisStore.client.zrank('blacklist', tokenRefresh));
        //const isRefreshTokenRevoked = Number.isInteger(await redisClient.zrank('blacklist', tokenRefresh));
        //await redisClient.quit();
        if (isRefreshTokenRevoked) {
            throw err;
        }
        ...
    }
}