Retry failed HTTP calls with RxJS

In this recipe, you're going to learn how to retry HTTP calls smartly with RxJS operators. We're going to use a technique called Exponential Backoff technique. Which means that we retry the http calls but with each next call having a delay more than the previous time for the attempt. And we stop after a number of maximum tries. Sounds exciting? Let's get into it

Getting ready

The app that we are going to work with resides in start/apps/chapter05/rx-retry-http-calls inside the cloned repository:

1. Open the code repository in your Code Editor.
2. Open the terminal, navigate to the code repository directory and run npm run serve rx-retry-http-calls with-server to serve the project with the backend server

This should open the app in a new browser tab and you should see the following:

Figure 5.13 – The rx-retry-http-calls running on http://localhost.4200

Let's jump into the recipe steps in the next section.

How to do it…...