Storm-topology-specific terminologies
A topology is a logical separation of programming work into many small-scale processing units called spout and bolt, which is similar to MapReduce in Hadoop. A topology can be written in many languages, including Java, Python, and lot more supported languages. In visual depictions, a topology is shown as a graph of connecting spouts and bolts. Spouts and bolts execute tasks across the cluster. Storm has two modes of operation, called local mode and distributed mode:
- In local mode, all processes of Storm and workers run within your code development environment. This is good for testing and development of topologies.
- In distributed mode, Storm operates as a cluster of machines. When you submit topology code to the Nimbus, Nimbus takes care of distributing the code and allocating workers to run your topology based on your configuration.
In the following figure, we have purple bolts; these receive a tuple or records from the spout above them. A tuple supports...