Bind validation results from ajax request to form model in mithril - fluentvalidation

Question

Hi I would like to bind html inputs with validation response model returned from API like that:
{"userName":[{"memberNames":["UserName"],"errorMessage":"Field User Name is required."}],"acceptTerms":[{"memberNames":["AcceptTerms"],"errorMessage":"Accepting terms is requried"}]}
And my component in mithril
var RegisterPage = {
vm: {
userName: m.prop(),
password: m.prop(),
confirmPassword: m.prop(),
acceptTerms: m.prop(false)
},
controller: function (args) {
this.title = 'Register new user account';
this.vm = RegisterPage.vm;
this.register = function (e) {
e.preventDefault();
apiRequest({ method: "POST", url: "http://localhost:12116/auth/register", data: RegisterPage.vm }).then(RegisterPage.vm.registerResult)
}
},
view: function (ctrl, args) {
return m('form.input-group',
[
m('.input-row', [m('label', 'Email'), m('input[type=email][placeholder=Your email address like myemail#email.com]', { onchange: m.withAttr("value", ctrl.vm.email) })]),
m('.input-row', [m('label', 'Password'), m('input[type=password][placeholder=your password]', { onchange: m.withAttr("value", ctrl.vm.password) })]),
m('.input-row', [m('label', 'Confirm password'), m('input[type=password][placeholder=your password]', { onchange: m.withAttr("value", ctrl.vm.confirmPassword) })]),
m('.input-row', [m('label', 'Accept terms and conditions'), m('input[type=checkbox]', { onchange: m.withAttr("checked", ctrl.vm.acceptTerms) })]),
m('button[type=submit].btn btn-positive btn-block', { onclick: ctrl.register }, 'Register account')
]);
}
}
I am looking for some generic solution. I would like to mark invalid fields with css class and add field validation message.
UPDATE
In my project I use some wrapper around m.request to get more details when 400 is thrown
function apiRequest(args) {
NProgress.start();
if (!args.unwrapError) {
args.unwrapError = function (data, xhr) {
if (xhr.status === 401)
{
layout.badRequestMsg(xhr.statusText);
}
NProgress.done();
return data;
}
}
if (!args.unwrapSuccess) {
args.unwrapSuccess = function (data, xhr) {
NProgress.done();
return data;
}
}
return m.request(args);
}