When user reaches “soft” of “hard” limit of requests per period, plugin checks, if user is a member of one of the groups, defined in configuration. If yes, plugin sends notification email to user email address.
Email example, when user reaches “soft” limit:
[Gerrit Code Review] User "username" reached the warning limit of "uploadpackperhourwarn" upload pack per "timelapseinminutes" minutes. This email is to inform that a user with "email@address" has exceeded a rate limit. Log: User "username" reached the warning limit of "uploadpackperhourwarn" upload pack per "timelapseinminutes" minutes. This is a send-only email address. Replies to this message will not be read or answered.
Email example, when user reaches “hard” limit:
[Gerrit Code Review] User "username" was blocked due to exceeding the limit of "uploadpackperhour" upload pack per "timelapseinminutes" minutes. XX min YY sec remaining to permits replenishing. This email is to inform that a user with "email@address" has exceeded a rate limit. Log: User "username" was blocked due to exceeding the limit of "uploadpackperhour" upload pack per "timelapseinminutes" minutes. XX min YY sec remaining to permits replenishing. This is a send-only email address. Replies to this message will not be read or answered.
Notification email module is encapsulated in com.googlesource.gerrit.plugins.ratelimiter.RateLimitReachedSender class. It uses RateLimiterEmailFormat.soy and RateLimiterEmailFormatHTML.soy templates. Templates are located in resources. It's designed to minimize user impact to email templates.