Before, a fallback http server was created to handle requests for
unknown virtual hosts even when `HTTPS_METHOD=nohttp`. (In this case,
all http vhosts would be unknown.) Likewise, a catch-all fallback
https server was still created even if `HTTPS_METHOD=nohttps`.
Now the fallback servers are created only if needed. This brings the
behavior in line with the documentation and user expectation. It will
also make it easier to implement a planned feature: different servers
on different ports.
Before, if neither the vhost-specific cert nor `default.crt` existed,
nginx-proxy would not create the https vhost. This resulted in nginx
either refusing the connection or serving the wrong vhost depending on
whether there was another https vhost with a certificate.
Now nginx-proxy always creates an https server for a vhost, even if
the vhost-specific certificate and the default certificate are both
missing. When both certs are missing, nginx is given empty
certificate data to make it possible for it to start up without an
error. The empty certificate data causes the user to see a TLS error,
which is much easier to troubleshoot than a connection refused error
or serving the wrong vhost.
In particular, reduce the nesting depth to make it easier to
understand what the code is doing by:
* converting an $O(nm)$ nested loop into two serial $O(n)+O(m)$
loops, and
* consolidating similar nested `if` cases.
to ensure that the version is always the first output line.
Also, always output `# nginx-proxy`, even if the version isn't known.
This makes it easier to find the start of the generated config in the
output of `nginx -T`.
Rationale for eliminating the check to see if the `DEBUG` environment
variable holds a true value:
* The `DEBUG` environment variable might be set on a container (for
purposes specific to that container, not `nginx-proxy`) to a value
that cannot be parsed as a bool, which would break `nginx-proxy`.
* It simplifies the template.
* It eliminates a cold code path.
* It avoids heisenbugs.
* It makes debugging easier for users.
Also delete the debug info tests, as they are fragile and they provide
limited value.
Alternatively, we could avoid collision with the container's use of
the `DEBUG` environment variable by using a container label [1] such
as `com.google.nginx-proxy.nginx-proxy.debug`. I think doing so has
dubious value, especially if we want to attempt backwards
compatibility with the `DEBUG` environment variable.
Fixes#2139
[1] https://docs.docker.com/engine/reference/commandline/run/#-set-metadata-on-container--l---label---label-file
Co-authored-by: Nicolas Duchon <nicolas.duchon@gmail.com>
