Basic setup of Golang SQL unit testing with dockertest

I am performing SQL Unit Testing using dockertest. This is just a simple connection to *sqlx.DB but somehow it is generating an error Error: EOF when connecting to the database. I am unable to identify the error and I may have configured it wrongly.

import (
	"fmt"
	"log"
	"os"
	"testing"
	
	_ "github.com/lib/pq"
	"github.com/jmoiron/sqlx"
	"github.com/ory/dockertest/v3"
	"github.com/ory/dockertest/v3/docker"
)

var (
	host     = "localhost"
	user     = "postgres"
	password = "postgres"
	dbName   = "db_test"
	port     = "5437"
	dsn      = "host=%s port=%s user=%s password=%s dbname=%s sslmode=disable timezone=UTC connect_timeout=30"
)

var resource *dockertest.Resource
var pool *dockertest.Pool
var testDB *sqlx.DB
var testRepo Repo

func TestMain(m *testing.M) {
	// connect to docker; fail if docker not running
	p, err := dockertest.NewPool("")
	if err != nil {
		log.Fatalf("could not connect to docker; is it running? %s", err)
	}
	pool = p

	opts := dockertest.RunOptions{
		Repository: "postgres",
		Tag:        "14.5", // same as docker compose
		Env: []string{
			"POSTGRES_USER=" + user,
			"POSTGRES_PASSWORD=" + password,
			"POSTGRES_DB=" + dbName,
		},
		ExposedPorts: []string{"5432"},
		PortBindings: map[docker.Port][]docker.PortBinding{
			"5432": {
				{HostIP: "0.0.0.0", HostPort: port},
			},
		},
	}

	resource, err = pool.RunWithOptions(&opts)
	if err != nil {
		// _ = pool.Purge(resource)
		log.Fatalf("could not start resource: %s", err)
	}

	if err := pool.Retry(func() error {
		var err error
		testDB, err = sqlx.Connect("postgres", fmt.Sprintf(dsn, host, port, user, password, dbName))
		if err != nil {
			log.Println("Error:", err)
			return err
		}
		return testDB.Ping()
	}); err != nil {
		_ = pool.Purge(resource)
		log.Fatalf("could not connect to database: %s", err)
	}

	err = createTables()
	if err != nil {
		log.Fatalf("error creating tables: %s", err)
	}

	code := m.Run()

	if err := pool.Purge(resource); err != nil {
		log.Fatalf("could not purge resource: %s", err)
	}

	testRepo = &repo{db: testDB}

	os.Exit(code)
}

func createTables() error {
	tableSQL, err := os.ReadFile("./testdata/tables.sql")
	if err != nil {
		fmt.Println(err)
		return err
	}

	_, err = testDB.Exec(string(tableSQL))
	if err != nil {
		fmt.Println(err)
		return err
	}

	return nil
}

func Test_pingDB(t *testing.T) {
	err := testDB.Ping()
	if err != nil {
		t.Error("can't ping database")
	}
}

Default max wait time for pool.Retry is one minute. Just guessing, maybe your postgres db container is not coming up in one minute.

Try increasing the MaxWait time with e.g. pool.MaxWait = 20 * time.Minute