This is exactly what I needed.Thanks guys. On Thu, Aug 6, 2015 at 4:14 PM, Joseph Beard <jos...@josephbeard.net> wrote:
> One approach that I can think of would be to place an event in Kafka (or > similar) every time you add or remove an IP from the DB. Then have a > second spout in your topology that listens for those events and sends them > along to your bolt. Your bolt would then listen to messages as normal for > filtering purposes but also listen for these blacklist events to in order > to update its in-memory blacklist state. You’ll need to initialize the > in-memory state of the blacklist when starting the bolt (in the prepare(…) > method). > > You will also need to use the ALL grouping for the blacklist events to > ensure that all of your bolt instances get the memo that the blacklist has > changed. Because of this, this approach would only be effective if the > volume of blacklist updates is significantly less than the volume of > messages that you’re processing. > > I hope that helps. Good luck! > > > Joe > — > Joseph Beard > jos...@josephbeard.net > > > On Aug 6, 2015, at 4:41 AM, Ritesh Sinha < > kumarriteshranjansi...@gmail.com> wrote: > > > > I need to write a bolt which processes the messages on the basis of IP. > Basically , i have a list of IP's stored in mongoDB.All the messages i get > will contain IP's, So , i need to check if that particular IP is present in > the list or not if it is present then i need to ignore the message else > process it. > > > > The list of IP is dynamic .There can be addition or deletion of IPs > after the topology has been deployed to storm. > > > > The problem is either I need to keep the IP is memory(but the changes > can't be reflected once the list is updated) or read it every time from > mongoDB, which makes the processing slow. > > > > Is there any way to implement it efficiently ? > > Is it possible to trigger any event if addition or deletion of IP has > happened in mongoDB ? > >
