use node-redis with node 8 util.promisify - node.js

Question

node -v : 8.1.2
I use redis client node_redis with node 8 util.promisify , no blurbird.
the callback redis.get is ok, but promisify type get error message
TypeError: Cannot read property 'internal_send_command' of undefined
at get (D:\Github\redis-test\node_modules\redis\lib\commands.js:62:24)
at get (internal/util.js:229:26)
at D:\Github\redis-test\app.js:23:27
at Object. (D:\Github\redis-test\app.js:31:3)
at Module._compile (module.js:569:30)
at Object.Module._extensions..js (module.js:580:10)
at Module.load (module.js:503:32)
at tryModuleLoad (module.js:466:12)
at Function.Module._load (module.js:458:3)
at Function.Module.runMain (module.js:605:10)
my test code
const util = require('util');
var redis = require("redis"),
client = redis.createClient({
host: "192.168.99.100",
port: 32768,
});
let get = util.promisify(client.get);
(async function () {
client.set(["aaa", JSON.stringify({
A: 'a',
B: 'b',
C: "C"
})]);
client.get("aaa", (err, value) => {
console.log(`use callback: ${value}`);
});
try {
let value = await get("aaa");
console.log(`use promisify: ${value}`);
} catch (e) {
console.log(`promisify error:`);
console.log(e);
}
client.quit();
})()

Answer 1

changing let get = util.promisify(client.get);
to let get = util.promisify(client.get).bind(client);
solved it for me :)

Answer 2

If you are using node v8 or higher, you can promisify node_redis with
util.promisify as in:
const {promisify} = require('util');
const getAsync = promisify(client.get).bind(client); // now getAsync is a promisified version of client.get:
// We expect a value 'foo': 'bar' to be present
// So instead of writing client.get('foo', cb); you have to write:
return getAsync('foo').then(function(res) {
console.log(res); // => 'bar'
});
or using async await:
async myFunc() {
const res = await getAsync('foo');
console.log(res);
}
culled shamelessly from redis official repo

Answer 3

You can also use Blue Bird Library plus monkey patching will do the trick for you.
For example:
const bluebird = require('bluebird')
const redis = require('redis')
async connectToRedis() {
// use your url to connect to redis
const url = '//localhost:6379'
const client = await redis.createClient({
url: this.url
})
client.get = bluebird.promisify(client.get).bind(client);
return client
}
// To connect to redis server and getting the key from redis
connectToRedis().then(client => client.get(/* Your Key */)).then(console.log)