captcha-server

captcha-server2.0

Ready to use CAPTCHAs for your website.

Features

• Customizable phrase length and possible characters
• Captcha will be generated on your server. Therefore, no tracking by third parties.
• No need to write extra APIs
• User can specify various event-handlers.

Getting Started

1. Server Side ( Back-end )

1. install captcha-server.
   npm install captcha-server --save
   if you want to use v1.0.0 then run
   npm install captcha-server@1.0.0 --save
2. create new captcha.

   var captchaServer = require('captcha-server');
   var captcha = new captchaServer(5, 'ABCDEFGHIJK012345');
   

   captcha constructor takes two optional parameters:
   • number of characters in captcha
   • possible characters in phrase
3. add captcha router to your express app.
   app.use('/', captcha.router());
   It adds two APIs ( for serving and tesing the captcha ) to your app.
   If you are not using Express framework, use captcha-server1.0.0
   But you have to wrrite your own APIs with v1.0.0
4. get information from captcha.
   you can get information about captcha using following functions:
   • captcha.passed() returns true or false based on whether user has passed the captcha or not.
   • captcha.failCount() returns the number of times user has submitted wrong answer.
   • captcha.reloadCount() returns the number of times captcha has been reloaded. Note that captcha reloads automatically if user submits wrong answer.
5. provide optional event listeners.
   captcha-server2.0.0 provides following events:

   captcha.on('reload', function(){
    // do something everytime captcha reloads
    console.log('reloaded');
    console.log(captcha.passed(), captcha.failCount(), captcha.reloadCount());
    });
   
    captcha.on('test', function(isPassed){
      // do something everytime user submits an answer
      // isPassed contains true or false based on right or wrong answer.
      console.log('tested ' + isPassed);
      console.log(captcha.passed(), captcha.failCount(), captcha.reloadCount());
    });
   
    captcha.on('pass', function(){
      // do something when user submits right answer
      console.log('passed');
      console.log(captcha.passed(), captcha.failCount(), captcha.reloadCount());
    });
   
    captcha.on('fail', function(){
      // do something everytime user submits wrong answer
      console.log('failed');
      console.log(captcha.passed(), captcha.failCount(), captcha.reloadCount());
    });
   

   Back-end of your app is ready to serve CAPTCHAs

2. Client Side ( Front-end )

captcha-client is used.

Installation

Add following tag to your html <script src="https://cdn.jsdelivr.net/gh/rupindr/captcha-client/captcha-client-1.0.0.min.js" ></script>

Usage

1. Create a div where you want to place the captcha.
   <div id="captcha-container" ></div>

2. Create a new captcha object.
   It takes two parameters:

   • DOM element that is container for captcha
   • API address where captcha-server is running.

   when object is created, div #captcha-container will be popoulated with a captcha.

   var captcha = new CaptchaClient(document.getElementById('captcha-container'), 'https://localhost:3001');

3. Adding event listeners.
   captcha-client provides following events:

      captcha.on('load', function(){
          console.log("Loaded");
          // do something when captcha loads first time
      });
      captcha.on('reload', function(){
          console.log("Reloaded");
          // do something when captcha is reloaded
      });
      captcha.on('pass', function(){
          alert("Passed");
          // do something when captcha test is passed by user
      });
      captcha.on('fail', function(){
          alert("Try Again");
          // do something when user enters wrong characters
      });
      captcha.on('test', function(passed){
          console.log('Tested. Result is: ' + passed);
          // do something when user clicks on the submit button of captcha
      });

4. Checking if captcha test is passed or not:
   Use property isPassed.

       if(captcha.isPassed){ //returns true if captcha is passed
           //do something
       }
   

Check out Captcha Example to see how to integrate front-end and back-end.

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code.