Norbert Hartl

mostly brackets and pipes

Recaptcha for Gemstone

Having public accessible register pages or components can be fun or hell. As soon as these are discovered by spam bots it is the latter one. A very popular method to prevent abuse is using a captcha. reCAPTCHA is a remote service that you can use to realize a captcha for your site. The idea is quite clever. Instead of distorting self made images they use scanned pieces that weren’t recognized by OCR software. The source is a big project that scans public books for archiving. Pieces that fail the OCR process are perfect candidates for being used in captchas. The whole point about captchas is having images that aren’t recognizable by software. I did a small module in smalltalk that enables you to embed a captcha into your site. Having a common API for doing stuff like networking and HTTP requests is not one of the strength of smalltalk. Everything differs a lot between the dialects. As I need this for a site that is running on gemstone this module will only work there. To be exact it will AFAIK only work in the current beta (GLASS-dkh.231) It is available here