Move default nginx root outside of first location

[nbauernfeind]

According to https://www.nginx.com/resources/wiki/start/topics/tutorials/config_pitfalls/#root-inside-location-block

It is bad practice to declare the primary root inside of each location of an nginx.conf.

Note that this block does not specify a location, but should share the same location as the / location.

    location ~* \.chunk.(?:css|js)$ {
        expires 1y;
        add_header Cache-Control 'public, immutable, max-age=31536000';
    }

Took me a hot minute to find out why I couldn't fetch static resources from a non-default location.

[devinrsmith]

LGTM, but I'll defer to @mofojed

[mofojed]

What error are you getting right now? What's the use case for serving up static files outside of our specified locations?

[nbauernfeind]

The error is a 404.

I've written up a blog post on how to deploy our setup without docker. It still relies on nginx (specifically because of the dependency on webdav). In my post I cluster all deephaven related items into a single folder. jsapi and the ide end up in /deephaven/html. The deephaven-core jars end up in /deephaven/lib. The logging configuration in /deephaven/resources. Storage for notebooks and layouts in /deephaven/storage. Envoy and SSL configuration ends up in /deephaven/config. I felt that this was more clear to a reader; whether or not they choose to set it up like this is up to them.

In particular the relevant piece of configuration is this:

    location / {
        root   /usr/share/nginx/html;
        index  index.html index.htm;

        # Caching is taken care of by etags
        # Settings expires -1 also sets the 'no-cache' Cache-Control header (http://nginx.org/en/docs/http/ngx_http_headers_module.html)
        expires -1;
        add_header Cache-Control 'must-revalidate, max-age=0';
    }

    # .chunk.* files are safe to cache, as they contain a sha in their file name
    location ~* \.chunk.(?:css|js)$ {
        expires 1y;
        add_header Cache-Control 'public, immutable, max-age=31536000';
    }

Notice how the second location block does not specify a root. It is root less. On Ubuntu this default is /usr/share/nginx/html -- which is why this works inside of the docker environment. But, IMO is inconsistent with how the first location is configured. There are three valid options forward: 1) drop the root in the first location block (as it is being set to the default), 2) specify the root in both locations, or 3) set a default root for the entire server block.

Nginx recommends the third option.

If you read the linked "config pitfalls" article -- specifically the section I've linked to, it actually says that it's a common mistake to add the root config option to each location. Instead it recommends doing as I've done in the PR; creating a default root and only overwriting if necessary (Note: it is overwritten for notebooks and layouts).