reactjs-captcha

BotDetect CAPTCHA React Component: Simple API integration for React 13/14/15/16+

For a comprehensive step-by-step integration guide please see our React Captcha Component Integration Guide.
The guide covers the integration with the following backends:

• ASP.NET (Core): web API with MVC6
• ASP.NET (Legacy): Web-API2, MVC1-5, Generic Handler
• Java: Servlet, Spring, Struts
• PHP: the plain PHP

To give you a hint how React Captcha Component works we pasted a few, not necessary up-to-date (and mostly frontend related), excerpts from it bellow.

Quick guide:

1) React Captcha Component Installation:

npm install reactjs-captcha --save

2) Setting Backend Captcha Endpoint

Endpoint configuration depends on which technology you use in the backend.

• ASP.NET-based captcha endpoint:

import { captchaSettings } from 'reactjs-captcha';

class App extends React.Component {

  constructor(props) {
    super(props);

    captchaSettings.set({
      captchaEndpoint: 
        'https://your-app-backend-hostname.your-domain.com/simple-captcha-endpoint.ashx'
    });
  }
  ...
}

export default App;

• Java-based captcha endpoint:

import { captchaSettings } from 'reactjs-captcha';

class App extends React.Component {

  constructor(props) {
    super(props);

    captchaSettings.set({
      captchaEndpoint: 
        'https://your-app-backend-hostname.your-domain.com/simple-captcha-endpoint'
    });
  }
  ...
}

export default App;

• PHP-based captcha endpoint:

import { captchaSettings } from 'reactjs-captcha';

class App extends React.Component {

  constructor(props) {
    super(props);

    captchaSettings.set({
      captchaEndpoint: 
        'https://your-app-backend-hostname.your-domain.com/botdetect-captcha-lib/simple-botdetect.php'
    });
  }
  ...
}

export default App;

3) Import React Captcha Component and Display Captcha In Your View

import { Captcha } from 'reactjs-captcha';

class App extends React.Component {

  ...

  render() {
    return (
      <Captcha captchaStyleName="yourFirstCaptchaStyle"
      ref={(captcha) => {this.captcha = captcha}} />
      <input id="yourFirstCaptchaUserInput" type="text" />
    )
  }

}

4) Captcha Validation: Client-side Code

// process the yourFormWithCaptcha on submit event
yourFormWithCaptchaOnSubmitHandler(event) {

  // the user-entered captcha code value to be validated at the backend side
  let userEnteredCaptchaCode = this.captcha.getUserEnteredCaptchaCode();

  // the id of a captcha instance that the user tried to solve
  let captchaId = this.captcha.getCaptchaId();

  let postData = {
    userEnteredCaptchaCode: userEnteredCaptchaCode,
    captchaId: captchaId
  };

  let self = this;

  // post the captcha data to the /your-app-backend-path on your backend.
  // make sure you import the axios in this view with: import axios from 'axios';
  axios.post(
    'https://your-app-backend-hostname.your-domain.com/your-app-backend-path',
    postData, {headers: {'Content-Type': 'application/json; charset=utf-8'}})
      .then(response => {
        if (response.data.success == false) {
          // captcha validation failed; reload image
          self.captcha.reloadImage();
          // TODO: maybe display an error message, too
        } else {
          // TODO: captcha validation succeeded; proceed with your workflow
        }
      });

  event.preventDefault();
}

5) Captcha Validation: Server-side Code

The userEnteredCaptchaCode and captchaId values posted from the frontend are used to validate a captcha challenge on the backend.

The validation is performed by calling the: Validate(userEnteredCaptchaCode, captchaId).

• Server-side captcha validation with ASP.NET Captcha is performed in the following way:

// C#
SimpleCaptcha yourFirstCaptcha = new SimpleCaptcha();
bool isHuman = yourFirstCaptcha.Validate(captchaCode, captchaId);

' VB.NET
Dim yourFirstCaptcha As SimpleCaptcha = New SimpleCaptcha()
Dim isHuman As Boolean = yourFirstCaptcha.Validate(captchaCode, captchaId)

• Server-side captcha validation with Java Captcha is performed in the following way:

SimpleCaptcha yourFirstCaptcha = SimpleCaptcha.load(request);
boolean isHuman = yourFirstCaptcha.validate(captchaCode, captchaId);

• Server-side captcha validation with PHP Captcha is performed in the following way:

$yourFirstCaptcha = new SimpleCaptcha();
$isHuman = $yourFirstCaptcha->Validate($captchaCode, $captchaId);

Documentation:

1. React Captcha Component Step-by-step Integration Guide -- read this one first

2. React Captcha Component Basic Example -- partial code walk-through

3. React Captcha Component Form Example -- partial code walk-through

Dependencies:

The current version of the React Captcha Component requires one of the following BotDetect CAPTCHA backends:

• ASP.NET v4.4.1+
• Java v4.0.Beta3.6+
• PHP v4.2.4+

Technical Support:

Through contact form on captcha.com.