HTTPS to a relay board could not work. Nearly every board that offers it signs
its own certificate — there is no authority anywhere that could have signed it —
so the request failed verification before it left.
A checkbox, per board, off by default. Not a blanket switch, because the other
HTTPS case is real and opposite: a board reached from outside through a proxy
with a genuine certificate, where verification is the only thing standing
between an antenna switch and the internet. Same setting, two boards, different
answers.
Off by default is only safe if the failure explains itself, so a certificate
error now names the box to tick. Go's own "x509: certificate signed by unknown
authority" is accurate and tells an operator nothing about what to do next.
Shown only once an https:// URL is actually in the board's configuration. A
board on plain HTTP has no certificate to argue about, and an option that cannot
matter yet is one more thing to wonder about.
The flag joins the driver cache key: ticking it has to rebuild the driver, or
the cached one would go on refusing the certificate with the verifying client it
already holds.
The boards that take a bare host — WebSwitch, KMTronic — keep verification. An
https:// typed there is the proxy case by construction, since they default to
plain HTTP on the LAN.
Three tests against a real self-signed TLS server: accepted with the box,
refused with a message naming it without the box, and one board's setting not
leaking into another's.
Network relay boards (WebSwitch/KMTronic/Dingtian) were always reached at
http://<host>, so a board on the LAN behind a reverse proxy — the common remote
setup where the operator's 80/443 already go to Nginx Proxy Manager — couldn't be
reached from outside. relayBase() now keeps a scheme the operator supplies
(https://relay.example.com, optional sub-path) and only defaults to http:// for a
bare host/host:port. UI hint + test added.
The station-control code rebuilt a fresh driver on every status poll and every
relay set. Stateful boards (Denkovi FTDI D2XX, USB-serial) hold an OS handle only
one opener can own, so the first poll opened the board and leaked the handle, and
every poll after failed with 'device in use' — the relays greyed out a second
after Save and auto-control never switched. Drivers are now cached per device and
reused, closed on config change. Adds a Test-connection button + detect feedback
in the device editor (reported by VK4MA).
rouggy