func NewDefaultConfig() *Config {
	return &Config{
		MaxRetries:         env.GetOrDefaultInt(EnvMaxRetries, 5),
		TTL:                env.GetOrDefaultInt(EnvTTL, 10),
		PropagationTimeout: env.GetOrDefaultSecond(EnvPropagationTimeout, 2*time.Minute),
		PollingInterval:    env.GetOrDefaultSecond(EnvPollingInterval, 4*time.Second),
		HostedZoneID:       env.GetOrFile(EnvHostedZoneID),
	}
}
NewDefaultConfig returns a default configuration for the DNSProvider.
package route53
import (
	"errors"
	"fmt"
	"math/rand"
	"strings"
	"time"
	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/client"
	"github.com/aws/aws-sdk-go/aws/request"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/route53"
	"github.com/go-acme/lego/v4/challenge/dns01"
	"github.com/go-acme/lego/v4/platform/config/env"
	"github.com/go-acme/lego/v4/platform/wait"
)
const (
	envNamespace = "AWS_"
	EnvAccessKeyID     = envNamespace + "ACCESS_KEY_ID"
	EnvSecretAccessKey = envNamespace + "SECRET_ACCESS_KEY"
	EnvRegion          = envNamespace + "REGION"
	EnvHostedZoneID    = envNamespace + "HOSTED_ZONE_ID"
	EnvMaxRetries      = envNamespace + "MAX_RETRIES"
	EnvTTL                = envNamespace + "TTL"
	EnvPropagationTimeout = envNamespace + "PROPAGATION_TIMEOUT"
	EnvPollingInterval    = envNamespace + "POLLING_INTERVAL"
)
type Config struct {
	MaxRetries         int
	TTL                int
	PropagationTimeout time.Duration
	PollingInterval    time.Duration
	HostedZoneID       string
	Client             *route53.Route53
}