Client Server REST API captcha implementation

Question

I\'m building client server REST application. Client side is based on Angular while server is PHP (not that it matters much anyhow).

What I am wondering if there are an

Answer 1

Google's new-ish reCaptcha is pretty slick. They have several easy to understand examples and usage scenarios.

https://www.google.com/recaptcha/intro/index.html

Edit: To address your specific question of how to implement this in a RESTful application, I'd make two files. One would be a public-facing file like index.php and the other would be a back-end file that would hold the private information.

I could copy/paste my previously-written how-to here, or I could just link you to the article I wrote 2 months ago.