Docker

Run the whole cluster on Docker: Postgres and the pool are swarm services on one overlay network. Use it on your machine, or on a server you run.

src/Cluster.ts

import * as ClusterDocker from "@alchemy.run/effect-cluster/Docker";
import * as Layer from "effect/Layer";

export const Database = ClusterDocker.Database("Cluster");

export const Default = ClusterDocker.SwarmPool("Default", { replicas: 2 }).pipe(
  Layer.provide(Database),
);

Install @alchemy.run/docker, and turn swarm mode on once with docker swarm init.

Docker swarmyour machine

overlay network

Databaseswarm service

data

named volume

DefaultSwarmPool · service

task 1runner

task 2runner

ApiDocker Service

The database, the pool's tasks and the Api share one overlay network. The Api reaches the gateway by the pool's name.

The database

ClusterDocker.Database runs Postgres as a one-replica swarm service, with its data on a named volume. Publish it on a host port to look inside:

src/Cluster.ts

import * as ClusterDocker from "@alchemy.run/effect-cluster/Docker";

export const Database = ClusterDocker.Database("Cluster", { port: 5433 });

The pool

ClusterDocker.SwarmPool runs a swarm service with replicas tasks. Each finds its own address among the service’s tasks, and they talk on the overlay network.

Call it from a container

Services on the database’s network reach the gateway by the pool’s name:

src/Api.ts

import * as Cluster from "@alchemy.run/effect-cluster";
import * as Docker from "@alchemy.run/docker";
import * as Effect from "effect/Effect";
import * as HttpServerResponse from "effect/http/HttpServerResponse";
import { Database } from "./Cluster.ts";
import { Room } from "./Room.ts";

export default class Api extends Docker.Service<Api>()(
  "Api",
  Effect.gen(function* () {
    const database = yield* Cluster.Database.Database;
    return {
      main: import.meta.url,
      port: 3000,
      ports: [{ external: 8080, internal: 3000 }],
      networks: database.network?.kind === "docker" ? [{ name: database.network.name }] : [],
    };
  }).pipe(Effect.provide(Database)),
  Effect.gen(function* () {
    const rooms = yield* Room;
    return {
      fetch: Effect.gen(function* () {
        const lobby = yield* rooms.getByName("lobby");
        return yield* HttpServerResponse.json({ members: yield* lobby.Join({ name: "sam" }) });
      }).pipe(Effect.orDie),
    };
  }),
) {}

To call it from your machine instead, publish the gateway with gatewayPort on the pool.

Every option, with its default, is in the reference: Database and SwarmPool.