Cannot read property 'dropBufferSupport' of undefined

Hi,
unfortunately I come across this error using ioredis in typescript:

TypeError: Cannot read property 'dropBufferSupport' of undefined at RedisManager.set (/Users/x/Documents/Github/x/backend/node_modules/ioredis/built/commander.js:110:26)

I use a standard setup and a simple test this.client = new Redis({ host: Config.redis.host, port: Config.redis.port, dropBufferSupport: false }); … this.client.on('ready', async () => { Logger.info("Redis connected and healthy."); try { await this.set('Test', 'X'); console.log(await this.get('Test')); this.health = true; } catch(err){ console.error(err); } });

Node-Version: 13.10.1 Redis-Version: 5.0.3 ioredis: 4.16.3

Help would be highly appreciated 😃

[alesbolka]

@JannikSt, From your example I would assume it’s a problem with the way you reference ioredis and use functions - when you use an arrow function, this context is retained from where you defined the this.client.on call. Try using a plain function over an arrow function, those can be bound and called with context supplied to them. Otherwise, a more elaborate example would help. I encountered this problem when trying to build a module interface in a file and just export the set and get functions from the module:

// wrong.js
const cache = new Redis(config);
module.exports = {
  set: cache.set,
  get: cache.get,
};

// working.js
const cache = new Redis(config);
module.exports = {
  set: async (key, value, ttl=30) => cache.set(key, value, 'EX', ttl),
  get: async (key) => cache.get(key),
};

// alternative.js
const cache = new Redis(config);
module.exports = {
  set: cache.set.bind(cache),
  get: cache.get.bind(cache),
};

[benallfree]

@alesbolka Thank you! This got me too…