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Show HN: A tiny QR code generator – my second webapp

10 points| udhb | 12 years ago |dl.dropboxusercontent.com | reply

11 comments

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[+] GeneralMayhem|12 years ago|reply
Looks like you've already learned the most important lesson of software engineering: don't reinvent the wheel. Offloading the real work to Google probably is the best way to build this app in most cases, but it makes the headline a little misleading, because you didn't actually write a QR generator, you just wrote a text box that proxies to a web API.
[+] shirkey|12 years ago|reply
Another important lesson: be careful in trusting your main functionality to a third party, as Google has already announced the infographics portion (including the QR code generator) has been deprecated, see: https://developers.google.com/chart/infographics/
[+] danielrmay|12 years ago|reply
Good effort, but you should go for sanitizing the user input before you go ahead and use it.

For example, if you enter "'/> Hellooooo!" into your textarea, you can see the result shows the text "Helloooo!'/>" being shown next to the QR code for "'/>".

This is hugely important when writing web applications - you can read a bit more from this stack overflow question: http://stackoverflow.com/questions/2794137/sanitizing-user-i...

You may also want to read up about XSS: http://en.wikipedia.org/wiki/Cross-site_scripting

EDIT: I realise this was just a small, simple, learning project, but it's important to learn and be mindful of these considerations.

[+] udhb|12 years ago|reply
Thank you very much!
[+] Sae5waip|12 years ago|reply
Yet another Google Chart APIs QR code "generator". Come on, seriously, its not so hard to generate it yourself.

(Since there is even a JavaScript library to do it for you there is absolutely no excuse to use Googles API)