basic_operations.js

const Redis = require("ioredis");
const redis = new Redis({
  port: process.env.redisPort,
  host: process.env.redisEndpoint,
  password: process.env.redisPW
});

// ioredis supports all Redis commands:
redis.set("foo", "bar"); // returns promise which resolves to string, "OK"

// the format is: redis[SOME_REDIS_COMMAND_IN_LOWERCASE](ARGUMENTS_ARE_JOINED_INTO_COMMAND_STRING)
// the js: ` redis.set("mykey", "Hello") ` is equivalent to the cli: ` redis> SET mykey "Hello" `

// ioredis supports the node.js callback style
redis.get("foo", function(err, result) {
  if (err) {
    console.error(err);
  } else {
    console.log(result); // Promise resolves to "bar"
  }
});

// Or ioredis returns a promise if the last argument isn't a function
redis.get("foo").then(function(result) {
  console.log(result);
});

redis.del("foo");

// Arguments to commands are flattened, so the following are the same:
redis.sadd("set", 1, 3, 5, 7);
redis.sadd("set", [1, 3, 5, 7]);
redis.spop("set"); // Promise resolves to "5" or another item in the set

// Most responses are strings, or arrays of strings
redis.zadd("sortedSet", 1, "one", 2, "dos", 4, "quatro", 3, "three")
redis.zrange("sortedSet", 0, 2, "WITHSCORES").then(res => console.log(res)); // Promise resolves to ["one", "1", "dos", "2", "three", "3"] as if the command was ` redis> ZRANGE sortedSet 0 2 WITHSCORES `

// Some responses have transformers to JS values
redis.hset("myhash", "field1", "Hello");
redis.hgetall("myhash").then(res => console.log(res)); // Promise resolves to Object {field1: "Hello"} rather than a string, or array of strings

// All arguments are passed directly to the redis server:
redis.set("key", 100, "EX", 10); // set's key to value 100 and expires it after 10 seconds

// Change the server configuration
redis.config("set", "notify-keyspace-events", "KEA");