Filter problematic characters

hackerspace-bootstrap / strichliste-web

DEPRECATED - frontend for the strichliste api

http://demo.strichliste.org/

MIT License

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Filter problematic characters #48

Closed izzy closed 9 years ago

izzy commented 9 years ago

Whitespace chars like U+200B should not be allowed as they allow the creation of optically identical usernames.

selection_014

schinken commented 9 years ago

Do you have a good method to filter those characters? I don't want to maintain a whitelist

Maybe this?

userInput = userInput.replace(/[\u200B-\u200D\uFEFF]/g, '');

izzy commented 9 years ago

Of course, a whitelist of UTF8 chars would be too tedious. Generally, there is no reason to block chars, except for a simple, small list of really bad characters. But I'm not sure which characters you would want to replace that are not already handled by your app. But for a general Idea:

All whitespace chars - the only needed char is a standard, breaking space (ASCII horizontal space, 0x20)
control characters

For those whitespaces: The German Wikipedia has a nice list.

schinken commented 9 years ago

I'm currently thinking about integrating this functionality to the server instead to the frontend.

This is just for me as a reminder: ;)

[\xA0\u1680\u2002-\u200b\u202F\u205F\u2060\u3000\uFEFF]+