Etherpad widget creation breaks if the pad name is too long

[jaywink]

Reported at https://github.com/vector-im/riot-web/issues/6039#issuecomment-517270591 by @florianjacob

I experience similar behaviour when when I use etherpad names that are too long: ABCDEFGHIJKLMNOPQRS as pad name, i.e. 20 chars long works just fine, but ABCDEFGHIJKLMNOPQRST, i.e. 21 chars long, break. I do get a 502 bad gateway and the not embeddable banana like in element-hq/element-web#9098, though, not such a padname is forbidden.

[Half-Shot]

The pad name is based upon the room_id so e.g. padName=!JKJFaFaqxqvnchMjfF:half-shot.uk_lalalala. If you are using matrix.org or half-shot.uk you are probably okay. If you are using vector.modular.im or wibblefibbledibble.ems.host, you're probably screwed.

[jaller94]

I suggest hashing the room id to get strings of a consistent length.

[Half-Shot]

The limit is imposed over at https://github.com/ether/etherpad-lite/blob/develop/src/node/db/PadManager.js#L195-L198, should we want to fix it there.

[jaywink]

Still an issue with etherpad 1.8.6

[fooness]

As it’s probably impossible to somehow work around this, because there’s no way to access the code of the scalar integration manager, this should please urgently be fixed. It’s a somewhat critical (usability-wise) bug and it’s open for more than a year.

On a side note, defining our own URL per widget manager would even be greater (like it is possible for BigBlueButton).

[emorrp1]

To flesh this out a little, I created an Etherpad named "Minutes" which gave the below URL. "Widget saved" was shown in green.

https://scalar.vector.im/etherpad/p/!qLhNfILESSCaasbRWB:freedombox.emorrp1.name_Minutes

Until you actually go to view that widget in the sidebar, at which point "Sorry, this content is not embeddable in Matrix" is shown with no way to figure out why. Visiting the URL directly says "Such a padname is forbidden" again without saying it's the custom name that's too long.

So apparently any rooms first created on my homeserver are forevermore limited to Etherpad names of 6 characters or fewer.

[sim6]

What about limit the form input length?

[t3chguy]

Given the ID includes the room ID, a pad name of 0 character could even be too long

[rcastelo]

Please, I'd appreciate if this bug with Etherpad name length limit is fixed somehow.

[justinbot]

Pad names are now UUIDs instead of the room name.