Allow graceful TLS key rotation

[jech]

This was initially reported by @tohojo.

Galène will automatically pick up any changes to its configuration files. It will not pick up a change to the TLS keys — the only way to rotate keys is to restart the server.

I can see two ways of doing graceful key rotation. The simple one is to stop the TLS listener and then start a new one; this will involve a couple of seconds of downtime, but will not interrupt currently connected users. The other one would be mutate the TLS configuration of the current listener (see (*tls.Certificate).GetCertificate), as is done by the letsencrypt library.

[athoune]

GetCertificate method, for just in time certificate read will only be used for new connections. Websocket will keep the connection opened for a long time.

Why do you care about certificate reload? paid certifcate are valid for years.
If you choose to use LE, using a proxy like Traefik or Caddy (and sharing web with other applications) will be more simple.
Integrating lego lib in galene is more robust than cron+certbot+kill -HUP.

[tohojo]

Mathieu Lecarme <notifications@github.com> writes:

`GetCertificate` method, for just in time certificate read will only be used for new connections. Websocket will keep the connection opened for a long time. Why do you care about certificate reload? paid certifcate are valid for years. If you choose to use LE, using a proxy like Traefik or Caddy (and sharing web with other applications) will be more simple.

But if you're *not* sharing the IP with other applications, that just means another service to configure...

Integrating lego lib in galene is more robust than cron+certbot+kill -HUP.

Why would that be more robust?

[athoune]

But if you're not sharing the IP with other applications, that just
means another service to configure...
You are using one IP per service ? ipv6 was done for you!

Using a complete HTTP server for handling multihosting, throtlling, bot ban … is just a standard. Few call it ingress.

Integrating lego lib in galene is more robust than cron+certbot+kill
-HUP.

Why would that be more robust?

that just means another service to configure, and a cron to miss.

[jech]

Galène is meant to work both behind a reverse proxy and directly exposed to the Internet. This is not open to discussion.

[athoune]

Sure, the discussion was more about lego integration (inside) vs certbot integration (outside).

[jech]

Fixed in b1babf5.