func installHostInfo(w http.ResponseWriter, r *http.Request, t auth.Token) error {
	allowed := permission.Check(t, permission.PermInstallManage)
	if !allowed {
		return permission.ErrUnauthorized
	}
	host, err := install.GetHostByName(r.URL.Query().Get(":name"))
	if errNf, ok := err.(*install.ErrHostNotFound); ok {
		return &errors.HTTP{Code: http.StatusNotFound, Message: fmt.Sprintf("Host %s not found.", errNf.Name)}
	}
	if err != nil {
		return err
	}
	w.Header().Set("Content-Type", "application/json")
	return json.NewEncoder(w).Encode(&host)
}
func installHostInfo(w http.ResponseWriter, r *http.Request, t auth.Token) error {
	allowed := permission.Check(t, permission.PermInstallManage)
	if !allowed {
		return permission.ErrUnauthorized
	}
	host, err := install.GetHostByName(r.URL.Query().Get(":name"))
	if errNf, ok := err.(*install.ErrHostNotFound); ok {
		return &errors.HTTP{Code: http.StatusNotFound, Message: fmt.Sprintf("Host %s not found.", errNf.Name)}
	}
	if err != nil {
		return err
	}
	w.Header().Set("Content-Type", "application/json")
	return json.NewEncoder(w).Encode(&host)
}
// title: install host info
// path: /install/hosts/{name}
// method: GET
// produce: application/json
// responses:
//   200: OK
//   401: Unauthorized
//   404: Not Found