CODEWITHSUNDEEP
ruby
Mudassir Ali
Mudassir Ali

Reputation: 8041

Implement real-time updating notification feature

I'd like to implement some visual indicator of various sections for the items whose status is pending in my app similar to facebook's / google plus unread notification indicator...I have written an API to fetch the count to be displayed, but I am stuck at updating it everytime an item gets added or deleted, I could think of two approaches which I am not satisfied with,

  • first one being making an API call related to the count whenever a POST or DELETE operation is performed
  • Second one being refreshing the page after some time span...

    I think there should be much better way of doing this from server side, any suggestion or any gem to do so?

    Upvotes: 0

    Views: 85

    • Answers (1)

    Matzi
    Matzi

    Reputation: 13925

    Even in gmail it is refreshed on client request. The server calculates the amount of new items, and the client initiates a request (probably with AJAX). This requires an almost negligible amount of data and process time, so probably you can get away with it. Various cache gems even can store the part of the page refreshed if no data changed since last request, which even solves the problem of calculating only when something changed.

    UPDATE:

    You can solve the problem basically two ways: server side push, and a client side query. The push is problematic, for various reasons, rarely used in web environment, at least as far as I know. Most of the pages (if not all) uses timed query to refresh such information. You can check it with the right tool, like firebug for firefox. You can see as individual requests initiated towards the server.

    When you fire a request trough AJAX, the server replies you. Normally it generates a page fragment to replace the old content with the new, but some cache mechanism can intervene, and if nothing changed, you may get the previously stored cache fragment. See some tutorial here, for various gems, one of them may fit your needs.

    If you would prefer a complete solution, check Faye (tutorial here). I haven't used it, but may worth a try, seems simple enough.

    Upvotes: 1

    Related Questions