Testcontainer support for golang

[devaljain1998]

Hey folks,
I have been trying to create a Redis cluster with test containers for my microservice in golang.

The redis-cluster works perfectly fine on my local with this command:

docker run -e "INITIAL_PORT=6000" -e "IP=0.0.0.0" -p 6000-6005:6000-6005 grokzen/redis-cluster:7.0.10

I have tried to translate this command in a golang testcontainer code:

package main

import (
	"context"
	"fmt"
	"github.com/docker/docker/api/types/container"
	"github.com/docker/go-connections/nat"
	"time"

	"github.com/redis/go-redis/v9"
	"github.com/testcontainers/testcontainers-go"
	"github.com/testcontainers/testcontainers-go/wait"
)

func main() {
	ctx := context.Background()

	req := testcontainers.GenericContainerRequest{
		ContainerRequest: testcontainers.ContainerRequest{
			Image:        "grokzen/redis-cluster:7.0.10",
			ExposedPorts: []string{"6000/tcp", "6001/tcp", "6002/tcp", "6003/tcp", "6004/tcp", "6005/tcp"},
			Env: map[string]string{
				"INITIAL_PORT": "6000",
				"IP":           "0.0.0.0",
			},
			WaitingFor: wait.ForLog("Ready to accept connections").WithPollInterval(5 * time.Second),
			HostConfigModifier: func(hostConfig *container.HostConfig) {
				hostConfig.PortBindings = nat.PortMap{
					"6000/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6000"}},
					"6001/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6001"}},
					"6002/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6002"}},
					"6003/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6003"}},
					"6004/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6004"}},
					"6005/tcp": []nat.PortBinding{{HostIP: "0.0.0.0", HostPort: "6005"}},
				}
			},
		},
		Started: true,
	}

	container, err := testcontainers.GenericContainer(ctx, req)
	if err != nil {
		fmt.Printf("Error: %v\n", err)
		return
	}
	defer container.Terminate(ctx)

	ip, err := container.Host(ctx)
	if err != nil {
		fmt.Printf("Error getting container host: %v\n", err)
		return
	}

	port, err := container.MappedPort(ctx, "6000")
	if err != nil {
		fmt.Printf("Error getting mapped port: %v\n", err)
		return
	}

	redisAddr := fmt.Sprintf("%s:%s", ip, port.Port())

	// Create a Redis cluster client
	rdb := redis.NewClusterClient(&redis.ClusterOptions{
		Addrs: []string{redisAddr},
	})

	// Ping the Redis cluster
	pong, err := rdb.Ping(ctx).Result()
	if err != nil {
		fmt.Printf("Error pinging Redis: %v\n", err)
		return
	}

	fmt.Printf("Redis PING response: %s\n", pong)
}

My code is not able to ping the redis cluster and it is giving the error stating Connection Refused.

Any hints about what can I can be doing wrong here?
cc: @Grokzen

[ivolkoff]

1. A proxying solution can be used on mac os
   https://golangexample.com/connect-directly-to-docker-for-mac-containers-via-ip-address/

2. The connection to the cluster goes to the 7000 port