nginx responding "301 moved permanently"

Consider the following nginx config file:

server {
    listen 443;
    ssl    on;
    ssl_certificate     /etc/tls/cert.pem;
    ssl_certificate_key /etc/tls/key.pem;
    location / {
        proxy_pass http://api.default.svc.cluster.local;
    }
}

All incoming TCP requests on 443 should redirect to my server running on api.default.svc.cluster.local:80 (which is a node REST-Api btw). This works fine, I can curl https://<nginx-IP>/ nginx and get a correct response, as expected.

Now, I'd like to change the location from / to /api, so I can fire a curl https://<nginx-IP>/api in order to get the same response as before.

1. Attempt

So I change the location line in the config to:

location /api {

Unfortunately this won't work, instead I get an error Cannot GET /api which is a node error, so obviously it gets routed to the api but something's still smelly.

2. Attempt

It seems as the trailing slash in an URI is required so I added it to the location:

location /api/ {

Now something changed. I won't get the same error as before, instead I get an "301 moved permanently". How can I fix my nginx config file?

Additional information regarding the environment

I'm using a kubernetes deployment that deploys the nginx reverse proxy incl. the config introduced. I then expose nginx using a kubernetes service. Also, I tried using kubernetes ingress to deal with this situation, using the same routes, however, the ingress service would respond with a default backend - 404 message.

via Ronin