AWS Redis local

In this example, we connect to a local Docker Redis instance for dev. While on deploy, we use Redis ElastiCache.

We use the docker run CLI to start a local Redis server. You don’t have to use Docker, you can run it locally any way you want.

docker run \
  --rm \
  -p 6379:6379 \
  -v $(pwd)/.sst/storage/redis:/data \
  redis:latest

The data is persisted to the .sst/storage directory. So if you restart the dev server, the data will still be there.

We then configure the dev property of the Redis component with the settings for the local Redis server.

dev: {
  host: "localhost",
  port: 6379
}

By providing the dev prop for Redis, SST will use the local Redis server and not deploy a new Redis ElastiCache cluster when running sst dev.

It also allows us to access Redis through a Resource link.

const client = Resource.MyRedis.host === "localhost"
  ? new Redis({
      host: Resource.MyRedis.host,
      port: Resource.MyRedis.port,
    })
  : new Cluster(
      [{
        host: Resource.MyRedis.host,
        port: Resource.MyRedis.port,
      }],
      {
        redisOptions: {
          tls: { checkServerIdentity: () => undefined },
          username: Resource.MyRedis.username,
          password: Resource.MyRedis.password,
        },
      },
    );

The local Redis server is running in standalone mode, whereas on deploy it’ll be in cluster mode. So our Lambda function needs to connect using the right config.

const vpc = new sst.aws.Vpc("MyVpc", { nat: "managed" });

const redis = new sst.aws.Redis("MyRedis", {
  dev: {
    host: "localhost",
    port: 6379,
  },
  vpc,
});

new sst.aws.Function("MyApp", {
  vpc,
  url: true,
  link: [redis],
  handler: "index.handler",
});

View the full example.