At the moment, in MDC, the UI is communicating to the OpenShift API server directly. In order to support in, the master config of the OpenShift API server needs to be updated to allow the MDC UI requests to be accepted (due to CORS configurations). In OpenShift 3, it is supported, but we have to restart the master node, which could cause the cluster downtime. In OpenShift 4, this is not officially supported until 4.2 (which will be released at the end of this month).

This could be a blocker to demonstrate MDS work on OpenShift 4. The solution explorer was facing the same issue and the solution they had is to add a simple proxy route in the server which will proxy the requests to the API server. This removes the need to use CORS completely (see https://github.com/integr8ly/tutorial-web-app/commit/578bab81a31240e2329dc8622966ce75d0985997).

Given that it is relatively easy to add the proxy route, I think we should do the same for MDC. This will reduce the amount of work required in the future when MDC is available from the operator hub, and developers don't need to enable CORS in development mode.

ping mziccard.