I built a captcha system with PHP and NodeJS.
Today I created a Captcha Embedder which allows you to easily implement a captcha into your HTML form.
Built with NodeJS:
To generate a captcha image.
Built with PHP:
To save captcha sessions generated by the NodeJS generator.
Here is how it works:
1. Someone embeds a script file in their HTML
2. Someone goes to that HTML page and loads the captcha
3. The embedder sends a message to the PHP server
4. The PHP server tells the NodeJS server to generate a Base64 image
5. The NodeJS server responds with the Base64 image
6. The PHP server saves an encrypted solution to the captcha as a file, and responds with the Base64 image, as well as the ID to the captcha
7. The captcha image appears on the page with the embedded captcha and you type the solution, and you submit the form
8. The form action page gets the POST parameters from the form request
9. The form action page sends a request to the PHP server and gets a response whether the captcha was solved correctly or not
10. The form action page does something if the captcha solution was successful, and something else if it was unsuccessful
Here is a simple demo that responds to the user on the form action page and says whether it was successful or not.