Validating username field

[wlingke]

Is there any way to specify a validation function for the username field (similar to password field)? For instance, if I wanted only emails, is there a way to check that the input is actually an email?

If not, I can write a middleware before it but would prefer the to use a passport local mongoose option if available.

[saintedlama]

Validating the username with some username rules should be best done in a http/express/koa/whatever middleware and not in this plugin.