3 ms·

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

10 points by udhb 13y ago

udhb 13y ago
and here is the first one - https://news.ycombinator.com/item?id=6392134 https://news.ycombinator.com/item?id=6392134
GeneralMayhem 13y ago
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 13y ago
  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/ https://developers.google.com/chart/infographics/
  - udhb 13y ago
    Thanks.
mconstable 13y ago
http://www.itwiz.co.uk/search/index.php http://www.itwiz.co.uk/search/index.php Just type "QR" then a space and whatever you want QR'd Loads of other services too Integrates with your browser's search bar too with http://www.itwiz.co.uk/search/index.php?search=%s http://www.itwiz.co.uk/search/index.php?search=%s
jorangreef 13y ago
I was hoping you had a much shorter embedded version of http://d-project.googlecode.com/svn/trunk/misc/qrcode/js/ http://d-project.googlecode.com/svn/trunk/misc/qrcode/js/
- udhb 13y ago
  Thanks for the link!
ismaelc 13y ago
https://www.mashape.com/search?query=qr https://www.mashape.com/search?query=qr
danielrmay 13y ago
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-input-before-adding-it-to-the-dom-in-javascript 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 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 13y ago
  Thank you very much!
Sae5waip 13y ago
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)

10 points by udhb 13y ago

udhb 13y ago

and here is the first one - https://news.ycombinator.com/item?id=6392134 https://news.ycombinator.com/item?id=6392134

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 13y ago
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/ https://developers.google.com/chart/infographics/
- udhb 13y ago
  Thanks.

mconstable 13y ago

http://www.itwiz.co.uk/search/index.php http://www.itwiz.co.uk/search/index.php Just type "QR" then a space and whatever you want QR'd Loads of other services too Integrates with your browser's search bar too with http://www.itwiz.co.uk/search/index.php?search=%s http://www.itwiz.co.uk/search/index.php?search=%s

jorangreef 13y ago

I was hoping you had a much shorter embedded version of http://d-project.googlecode.com/svn/trunk/misc/qrcode/js/ http://d-project.googlecode.com/svn/trunk/misc/qrcode/js/

udhb 13y ago
Thanks for the link!

ismaelc 13y ago

https://www.mashape.com/search?query=qr https://www.mashape.com/search?query=qr

danielrmay 13y ago

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-input-before-adding-it-to-the-dom-in-javascript 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 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 13y ago
Thank you very much!

Sae5waip 13y ago

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)