Action operators

To close this chapter, we will cover some helpful operators that can assist in debugging as well as getting visibility into an Observable chain. These are the action or doOn operators.

doOnNext(), doOnComplete(), and doOnError()

These three operators: doOnNext(), doOnComplete(), and doOnError() are like putting a mini Observer right in the middle of the Observable chain.

The doOnNext() operator allows you to peek at each emission coming out of an operator and going into the next. This operator does not affect the operation or transform the emissions in any way. We just create a side-effect for each event that occurs at that point in the chain. For instance, we can perform an action with each string...