prow/pod-utils/decorate/podspec.go
func cookiefileVolume(secret string) (coreapi.Volume, coreapi.VolumeMount, string) {
	// Separate secret-name/key-in-secret
	parts := strings.SplitN(secret, "/", 2)
	cookieSecret := parts[0]
	var base string
	if len(parts) == 1 {
		base = parts[0] // Assume key-in-secret == secret-name
	} else {
		base = parts[1]
	}
	var cookiefileMode int32 = 0400 // u+r
	vol := coreapi.Volume{
		Name: "cookiefile",
		VolumeSource: coreapi.VolumeSource{
			Secret: &coreapi.SecretVolumeSource{
				SecretName:  cookieSecret,
				DefaultMode: &cookiefileMode,
			},
		},
	}
	mount := coreapi.VolumeMount{
		Name:      vol.Name,
		MountPath: "/secrets/cookiefile", // append base to flag
		ReadOnly:  true,
	}
	return vol, mount, path.Join(mount.MountPath, base)
}
func cookiefileVolume(secret string) (coreapi.Volume, coreapi.VolumeMount, string) {
	// Separate secret-name/key-in-secret
	parts := strings.SplitN(secret, "/", 2)
	cookieSecret := parts[0]
	var base string
	if len(parts) == 1 {
		base = parts[0] // Assume key-in-secret == secret-name
	} else {
		base = parts[1]
	}
	var cookiefileMode int32 = 0400 // u+r
	vol := coreapi.Volume{
		Name: "cookiefile",
		VolumeSource: coreapi.VolumeSource{
			Secret: &coreapi.SecretVolumeSource{
				SecretName:  cookieSecret,
				DefaultMode: &cookiefileMode,
			},
		},
	}
	mount := coreapi.VolumeMount{
		Name:      vol.Name,
		MountPath: "/secrets/cookiefile", // append base to flag
		ReadOnly:  true,
	}
	return vol, mount, path.Join(mount.MountPath, base)
}
// cookiefileVolumes converts a secret holding cookies into the corresponding volume and mount.
//
// Secret can be of the form secret-name/base-name or just secret-name.
// Here secret-name refers to the kubernetes secret volume to mount, and base-name refers to the key in the secret
// where the cookies are stored. The secret-name pattern is equivalent to secret-name/secret-name.
//
// This is used by CloneRefs to attach the mount to the clonerefs container.
// The returned string value is the path to the cookiefile for use with --cookiefile.