code: func NewWebFrontEndImpl(
  	scope metrics.Scope,
  	clk clock.Clock,
  	keyPolicy goodkey.KeyPolicy,
  	certificateChains map[string][]byte,
  	logger blog.Logger,
  ) (WebFrontEndImpl, error) {
  	nonceService, err := nonce.NewNonceService(scope)
  	if err != nil {
  		return WebFrontEndImpl{}, err
  	}
  
  	return WebFrontEndImpl{
  		log:               logger,
  		clk:               clk,
  		nonceService:      nonceService,
  		keyPolicy:         keyPolicy,
  		certificateChains: certificateChains,
  		stats:             initStats(scope),
  		scope:             scope,
  	}, nil
  }
docs: // NewWebFrontEndImpl constructs a web service for Boulder