This is easy since we did the option parsing cleanup, but it has the
effect that plugins are launched from the lightning-dir. Now
we have dynamic plugins, this means startup and post-startup plugins
experience the same environment.
This is absolutely a desirable thing: they can just drop files in
their cwd rather than having to move (including, I might note, core
files!).
We also highlight the change in various places (and a drive-up update
of PLUGINS.md which says you have to use --plugin).
The next patch adds a backwards compatibility wedge for old users of
relative plugin paths.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This was deeply surprising to me; there's a difference between a value not being
specified, and it being specified as "".
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This also allows plugins to do "hold invoices" a-la LND, useful for
just-in-time inventory handling.
We're careful to handle the invoice getting paid behind our backs, and
the incoming HTLC going away.
Once @cdecker's sphinx rework is in, we can also hand the raw payload
to the invoice_payment_hook, for special effects.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
In theory we could allow a db_write-using plugin to have other
hooks/commands by embargoing their other responses until the exclusive
period is over. That would be nice for a 'dbmirrorinfo' command, for
example.
The other option would be to *always* go exclusive on a db_write-using
plugin, so responses can never get intermingled.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>