Cloud Native Programming with Golang

Enabling CORS in the backend services

Before testing the frontend application, you will need to make sure that the backend services (more precisely, both the event service and the booking service) support Cross-Origin Resource Sharing (CORS). Otherwise, your browser will not execute HTTP requests to any of your backend services, when the frontend is served on http://localhost:8080 and the backend services run on other TCP ports.

In principle, CORS consists of nothing more than a few additional headers that need to be present in the HTTP response. For example, to allow AJAX requests from another domain, the HTTP response needs to contain an Access-Control-Allow-Origin header. An HTTP response with such a header might look like this:

HTTP/1.1 ...