Google reCaptcha Verification -

i'm little confused opening paragraph of article: https://developers.google.com/recaptcha/docs/verify

when use third method validate (i.e. `data-callback' attribute), mean there's no longer need post https://www.google.com/recaptcha/api/siteverify end? 100% client-side captcha?

it means post ajax , when callback if successful or not can have javascript function allow submit/post or whatever action need do. use callback allow login button submit , if has not been completed button remains disabled. still need submit challenge google can verify if successful. here simplified example.

<div class="g-recaptcha" id="login" data-callback="captcha_filled"              data-expired-callback="captcha_expired" data-sitekey="xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"></div>  function captcha_filled() {     $("#submitlogin").prop('disabled', false); }