publish-subscribe

I am in the beginning phases of designing a system that will be event-driven architecture (basic pub/sub). The actual tools and frameworks have not been selected yet, so this question is more conceptual than technology specific (though it will be done in .Net). A nearly perfect analogy for the situation is a financial trading system. Imagine a server that is constantly receiving market data (in real time or at intervals--it doesn't matter). The server will publish pricing updates for specific securities. For the purpose of this question, let's say there are 1000 securities that the server is

I am exploring redis to do pub/sub. I wanted to write a script that uses redis-cli to subscribe to a channel and dump whatever is published to a file. What I notice however is that redis-cli subscripe channel > output does not quite work. I'd appreciate any help very much. Regards, Kashyap This is because there is no automatic flush of stdout when redis-cli displays the messages associated to the subscription. So the last messages before stopping redis-cli do not appear in the output file. There is no option you can use to enforce a systematic flush, redis-cli.c needs to be patched. In Redis

Based on this answer about how to scale Orion Context Broker with load balancing https://stackoverflow.com/a/33068119/3706998 what should be the behavior of subscriptions and also notifications? Witch server should it come from? What is the workflow? Could it cause some disturbe or cloned subscriptions ? Let's consider different cases, depending on subscription cache usage. Let's consider two Orion nodes (A and B) without loss of generality, both sharing the same MongoDB instance. Using subscription cache (i.e. -noCache is not set) The subscription creation request is dispatched to some of the

I'm trying to figure out a good way to create tutorials for using Meteor apps. Visually, I've figured out a good approach, and packed this into a smart package: https://github.com/mizzao/meteor-tutorials . However, there is a second piece that turns out to be rather hard to figure out. In many cases, a tutorial app needs to be loaded with fake data, to demonstrate the interface to the user without requiring it to be populated with real data that may be hard to generate. (For example, see https://www.planapple.com/trip/demo/349/ which is a demo for PlanApple). In Meteor, since the content of an

Suppose I created a JMS Topic (PropertiesTopic) with one subscriber (PropertiesSubscriber). PropertiesSubscriber is running in a load balanced application server cluster as shown in the picture below. alt text http://www.freeimagehosting.net/uploads/be28c03781.png When a message is delivered to PropertiesTopic, do all the instances of PropertiesSubscriber running on different app servers get that message or does the message get delivered to only one PropertiesSubscriber instance running on an app server determined by the load balancer? JMS 2.0 introduces shared subscriptions . These allow

I have a C++ Windows application. I am dealing with a publisher-subscriber situation, where one of my classes (publisher) generates data periodically and hands it off to another class (subscriber) which is constantly waiting to receive notification from the publisher. I am new to design patterns, and I looked up common implementations for publisher subscriber models, I noticed they are usually quite old, and they usually involve maintaining lists of pointers to objects. I was wondering if there is a better way of coding publisher subscriber model using C++ 11. Or using an entirely different