A small Docker-based build setup to create and build Go code with Nakama server.

docker-compose.yml

version: '3'
services:
  postgres:
    container_name: game_backend_postgres
    environment:
      - POSTGRES_DB=nakama
      - POSTGRES_PASSWORD=localdb
    expose:
      - "8080"
      - "5432"
    image: postgres:9.6-alpine
    ports:
      - "5432:5432"
      - "8080:8080"
    volumes:
      - data:/var/lib/postgresql/data

  nakama:
    build: .
    container_name: game_backend
    depends_on:
      - postgres
    entrypoint:
      - "/bin/sh"
      - "-ecx"
      - >
        /nakama/nakama migrate up --database.address postgres:localdb@postgres:5432/nakama &&
        exec /nakama/nakama --database.address postgres:localdb@postgres:5432/nakama
    expose:
      - "7349"
      - "7350"
      - "7351"
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:7350/"]
      interval: 10s
      timeout: 5s
      retries: 5
    links:
      - "postgres:db"
    ports:
      - "7349:7349"
      - "7350:7350"
      - "7351:7351"
    restart: unless-stopped

volumes:
  data:

Dockerfile

FROM heroiclabs/nakama-pluginbuilder:3.2.0 AS builder

ENV GO111MODULE on
ENV CGO_ENABLED 1

WORKDIR /backend
COPY . .

RUN go build --trimpath --mod=vendor --buildmode=plugin -o ./backend.so

FROM heroiclabs/nakama:3.2.0

COPY --from=builder /backend/backend.so /nakama/data/modules

go.mod

module github.com/account/reponame

go 1.16

require github.com/heroiclabs/nakama-common v1.13.0

main.go

package main

import (
	"context"
	"database/sql"
	"github.com/heroiclabs/nakama-common/runtime"
)

//noinspection GoUnusedExportedFunction
func InitModule(ctx context.Context, logger runtime.Logger, db *sql.DB, nk runtime.NakamaModule, initializer runtime.Initializer) error {
	logger.Info("Backend loaded.")
	return nil
}

To rebuild the container when code is changed use:

docker-compose -f ./docker-compose.yml up -d --build nakama

You can see which containers are active with the docker ps command.

You must also remember to run before you run the first build via Docker:

go mod vendor

This ensures that the dependencies for the project are local to the filesystem when the build runs. For more information see Go modules and vendored dependencies.