Allow plus (+) character in username

[skroczek]

Steps to reproduce

1. Create user with username containing plus char

Expected behaviour

User should be created

Actual behaviour

An error message with text "Only the following characters are allowed in a username: "a-z", "A-Z", "0-9", and "_.@-'"" occured.

[MorrisJobke]

cc @blizzz @nickvergessen @rullzer Opinion on this?

[nickvergessen]

causes behaviour problems, because " " is replaced with "+" on urlencode, so we would need to change this everywhere with the full trail of problems.

[MorrisJobke]

causes behaviour problems, because " " is replaced with "+" on urlencode, so we would need to change this everywhere with the full trail of problems.

Full ack.

[skroczek]

urlencode encodes " " as +, that's true. But it encodes '+' as '%2B', so I'm not sure if it would be such a big problem. A real problem exists, if you mix urldecode and rawurlencode. In this case, the already allowed white space leads to a problem:

<?php
// Result: [email protected]
echo rawurldecode(urlencode('foo [email protected]'));

All other combinations of rawurldecode and urlencode with '+' and ' ' are fine. And this problem already exists in the current code, so allowing the plus character is not that bad.

[blizzz]

👎 No fan of adding strange characters there. It's not supposed to be a user facing value anyhow.

[skroczek]

@blizzz I understand, that for commonly used usernames plus must sound as a strange character. But if you allow email addresses as usernames, what you are doing right now, it isn't. Even gmail allows + as a delimiter to tag mail addresses.
But I think it would actually be the best if the characters could be configured. However, I fear that it would take a much greater effort to implement this.

[nickvergessen]

But I think it would actually be the best if the characters could be configured.

No, that does not help at all. Apps need to know what they have to expect. So they would always have to implement for the biggest result set anyway. The thing is if we all of a sudden allow new characters that might cause undefined big problems for apps.

Counting all the Nops in here I see 4 so far, so I'm closing this for now.

[skroczek]

Well, that's a pity. Now I have to think about a workaround 🤔. Maybe next time. ☺️

[nickvergessen]

Workaround: $uid = str_replace('+', '-', $uid); in the right place.
If you have 2 people with the same email just one using + and the other one - that's bad luck

[Escubaer]

Some of my users really require this for google emails as user names ... maybe time to reconsider: owncloud/core#36613