Merge pull request #4161 from shaedrich/pubsub

Create topic "Publish-subscribe pattern"

topics/pubsub/index.md

@@ -0,0 +1,10 @@
+---
+aliases: publish-subscribe-pattern, publish-subscribe
+topic: pubsub
+display_name: Publish-subscribe pattern
+short_description: The publish-subscribe pattern is a messaging pattern where the consumer subscribes to the provider.
+related: message-queue, message-oriented-middleware, message-passing, event-bus, event-handlers, event-listener, message-bus, event-sourcing, observer-pattern, event-driven-programming
+released: 1987
+wikipedia_url: https://en.wikipedia.org/wiki/Publish%E2%80%93subscribe_pattern
+---
+The **publish-subscribe pattern** (short: **pubsub**) is an event handling and messaging pattern where the consumer _subscribes_ to the provider, which in return can then _publish_ a message that can be picked up and processed by each subscribed consumer.