This is necessary to eliminate confusing naming conventions, since now
we have Manager types, having an issuer called ACMEManager was
confusing.
CertificateManager is a redundant name as this package is called
CertMagic, so that a Manager manages certificates should be obvious.
It's also more succinct. Plus, it's consistent with Issuer which is not
named CertificateIssuer.
Breaking changes; thank goodness we're not 1.0 yet 😅 - read on!
This change completely separates ACME-specific code from the rest of the
certificate management process, allowing pluggable sources for certs
that aren't ACME.
Notably, most of Config was spliced into ACMEManager. Similarly, there's
now Default and DefaultACME.
Storage structure had to be reconfigured. Certificates are no longer in
the acme/ subfolder since they can be obtained by ways other than ACME!
Certificates moved to a new certificates/ subfolder. The subfolders in
that folder use the path of the ACME endpoint instead of just the host,
so that also changed. Be aware that unless you move your certs over,
CertMagic will not find them and will attempt to get new ones. That is
usually fine for most users, but for extremely large deployments, you
will want to move them over first.
Old certs path:
acme/acme-staging-v02.api.letsencrypt.org/...
New certs path:
certificates/acme-staging-v02.api.letsencrypt.org-directory/...
That's all for significant storage changes!
But this refactor also vastly improves performance, especially at scale,
and makes CertMagic way more resilient to errors. Retries are done on
the staging endpoint by default, so they won't count against your rate
limit. If your hardware can handle it, I'm now pretty confident that you
can give CertMagic a million domain names and it will gracefully manage
them, as fast as it can within internal and external rate limits, even
in the presence of errors. Errors will of course slow some things down,
but you should be good to go if you're monitoring logs and can fix any
misconfigurations or other external errors!
Several other mostly-minor enhancements fix bugs, especially at scale.
For example, duplicated renewal tasks (that continuously fail) will not
pile up on each other: only one will operate, under exponential backoff.
Closes#50 and fixes#55
Also adjust clients so that they use the configured HTTPPort or
HTTPSPort for solving challenges, if different from the default
challenge port (not as preferred as the Alt*Port values, of course)
