A small generic function for retrying in go.

main.go

func main() {
  db, err := util.Retry(120, time.Second, func() (*pgxpool.Pool, error) {
      return pgxpool.Connect(...)
  })
  if err != nil {
    log.Fatal("failed to initialize new postgres db pool")
  }
}

retry.go

package util

import (
	"fmt"
	"time"
)

// Retry tries to perform an action and retries on error for n times with a wait
// duration in between.
func Retry[T any](n int, wait time.Duration, action func() (*T, error)) (*T, error) {
	var result *T
	var err error
	for i := 0; i < n; i++ {
		if result, err = action(); err != nil {
			fmt.Printf("attempt #%d, retrying after wait period", i)
			time.Sleep(wait)
		} else {
			break
		}
	}

	if err != nil {
		return nil, fmt.Errorf("failed after retrying %d times with error: %w", n, err)
	}

	return result, nil
}