@startuml
title Notification
|Server|
partition Event {
    start
        :Article is modified;
        :Send message to "notification" exchange (RabbitMQ);
        :RabbitMQ send message to "push" and "email" queue;
    stop
}
split
    partition Email {
        -[hidden]->
        :Consume "email" queue<
        repeat :get next notification;
        :Get followers of article from DB;
        while (loop on followers)
             :Send email to the citizen>
        endwhile
        :ACK>
        repeat while()
        detach
    }
splitagain
    partition Push {
        -[hidden]->
        :Consume "email" queue<
        repeat :get next notification;
        :Get followers of article from DB;
        while (loop on followers)
             :Send notification message to redis>
        endwhile
        :ACK>
        repeat while()
        detach
    }
splitagain
    partition "Notification direct" {
        -[hidden]->
        |Client|
        start
        :Client arrive on the web site;
        :Connect to the websocket;
        |Server|
        :Get citizen notification
        from redis;
        while (on each notifications)
            :Send notification to websocket>
        endwhile(no notification left)
        |Client|
        :show notification;
        |Server|
        :Subscribe to redis event;
        repeat :On new notification;
        :Get new notification from redis;
        :Send notification to websocket>
        |Client|
        :show notification;
        |Server|
        repeat while (wait notification)
        detach
    }
endsplit


@enduml