open webapplication from desktop application

Question

Doctor is end user of this application Doctor opens desktop application on his pc which is not developed by us. We provide interface to desktop application via interop dll's. Desktop application call interface and through it they call our integration exe which includes some services which sits on doctors pc. This integration exe further creates session id, validates certificate on doctors pc with our database and at last it open browser with our webapplication created in angularjs.

Now i will explain what issues we face due to this..

previously this was working because webapplication was in http and so was wcf service aka localhost service in http. Client told we cannot host webapplication in http and we had to use https. But https webapplication cannot talk to local service hosted in http , so we had to change to use https for communicating with localhost services. So we had to introduce self signed certificates. This was also working ok till last month when chrome came with policy that it will not allow localhost certificate and suddenly on browser we get error about accepting certifcate.

what does localhost service do?

a. Get access token by passing the session Id to login the application from desktop application .

b. Pass XML message to desktop application to Sign

c. Get Available Printers in the network.

d. Intimate browser close event to desktop application to close the session.

What we need to do now

Find a way to totally avoid localhost service so we need to change architecture or first come up with approach

Answer 1

We ran into a similar issue in the software that I work on. We ended up using the same approach as Spotify (the important part is bolded):

With the requirement to use HTTPS, a valid SSL certificate is needed to avoid browsers complaining. Spotify has worked around this problem by registering a domain (*.spotilocal.com) that merely points to 127.0.0.1. But rather than connecting to the top domain, they use a wildcard domain and connect to a random subdomain each time (for example abcrjdknsa.spotilocal.com). The reason for this is to avoid the browser’s max connection limit per domain, enabling more tabs in the browser to concurrently use their API at the cost of an extra DNS lookup.

Implementing this approach requires two steps:

1. Register a domain and purchase a certificate for it.
2. In the installer for your local service, modify the hosts file to point the domain to 127.0.0.1.

As you can see, this does not require any changes to either your client or server code, just the installer.