The documentation is sparse below is a simple working example of a Invisible reCAPTCHA client server setup using client side JavaScript and a NodeJS server.
This example is setup as a very simple voting API endpoint where you POST your email along with your reCAPTCHA response. The API will return a different message along with the submitted email depending on wether you passed the reCAPTCHA challenge or not.
<html>
<head>
<script src="https://www.google.com/recaptcha/api.js"></script>
</head>
<body>
<!-- This div can be completely hidden the recaptcha lib just needs it to pull the sitekey, callback, and other details from it -->
<div class="g-recaptcha"
data-sitekey="6LeM9TwUAAAAAPKuYGNfnPFKX9EQRhs_5D1aiKfN"
data-callback="recaptchaSubmit"
data-size="invisible">
</div>
</body>
</html>var voteStore = null;
function recaptchaSubmit(recaptchaResponse) {
var data = {
email: voteStore.email,
recaptchaResponse: recaptchaResponse,
};
$.post('https://example.com/verifyRecaptcha', data)
.done(function(response) {
console.log('Success voting', response);
})
.fail(function(error) {
console.log('Error voting', error);
})
.always(function() {
voteStore = null;
grecaptcha.reset();
});
}
function vote(email, teamId) {
voteStore = { email: email };
grecaptcha.execute();
}const bodyParser = require('body-parser');
const express = require('express');
const app = express();
const { to } = require('await-to-js');
app.use(bodyParser.json());
app.post('/vote', (req, res) => {
const { email, recaptchaResponse } = req.body;
const [error, recaptchaResult] = await to(
verifyRecaptcha(req, recaptchaResponse)
);
if (recaptchaResult.success) {
return res.json({ result: `Passed captcha you are a human ${email}` });
}
return res.json({ result: `Failed captcha you are a bot ${email}` });
});
async function verifyRecaptcha(req, clientResponse = '') {
const secret = process.env.RECAPTCHA_SECRET_KEY;
const remoteip =
req.headers['x-forwarded-for'] ||
req.connection.remoteAddress ||
req.socket.remoteAddress ||
req.connection.socket.remoteAddress;
const url = `https://www.google.com/recaptcha/api/siteverify?secret=${secret}&response=${clientResponse}&remoteip=${remoteip}`;
const headers = headersFactory()('post', {
secret,
response: clientResponse,
remoteip,
});
const [error1, response] = await to(fetch(url, headers));
if (error1) throw error1;
const [error2, responseBody] = await to(response.json());
if (error2) throw error2;
return responseBody;
}