Dokku: Route subdomain to a path in a Dokku app using Nginx

[natanrolnik]

I have a few apps running in a aws instance with Dokku. I'm using virtual hostname, and together with some DNS configuration of my registered domain, I have the following for one of them: mydomain.com is a CNAME record pointing to the aws instance address, and Dokku+nginx take care of redirecting to the correct app/process.

The path for all API calls is /parse, as I'm using the open source Parse Server. The final server url is mydomain.com/parse.

What I want to achieve, ideally, is the following: api.mydomain.com gets redirected to mydomain.com/parse, api.mydomain.com/someFunction to mydomain.com/parse/someFunction and so on.

When researching to see how this may be possible, I found that this can be done easily with nginx, like explained here in this answer.

I can even change manually the nginx config file, but I'm afraid that it will be overwritten in future changes. How can this ideally be achieved with nginx on Dokku?

[josegonzalez]

You can use a customized nginx.conf.sigil in your application's repository root as explained in the nginx configuration documentation here. Short of us changing completely how we do custom nginx configuration - which we just recently did, so it's very unlikely - this is the safest route.

[natanrolnik]

@josegonzalez Thanks for the quick response, I appreciate, and apologize if this is not the ideal channel to ask. Also, thanks for all the efforts in Dokku, it's really useful.
I saw this page earlier today, but couldn't understand exactly how to do it. Is there a default nginx.conf.sigil I can start from?

[josegonzalez]

The example template on that page should give you the output you'd currently get with dokku's defaults.