Mostly comments and docs: some places are actually paths, which
I have avoided changing. We may migrate them slowly, particularly
when they're user-visible.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
So far we were papering over the actual error with a generic string
that isn't very useful. Now we decode the error and forward it through
the grpc layer as well (though still as a string).
This is likely inherited from bitcoind, and a bit awkward for us, so
we parse it into a classic struct, but serialize it back into the
bitcoind format when talking to the RPC.
We are inferring the field numbers on the fly, which isn't really
compatible with the way GRPC field numbers work, i.e., they must be
stable while the IDL file evolves. So far when a field was added in
the middle of a struct or removed all subsequent fields would get
renumbered, essentially breaking any client that was using the old
scheme.
We now add a meta file `.msggen.json` that keeps track of the numbers
assigned so far, so they can be reused, and new ones can be generated
not to conflict with existing ones. This file is intentionally kept
generic, so other generators can add more information that has to be
managed across runs.
Changelog-None
We wrap emitted messages into a JSON-RPC notification envelope and
write them to stdout. We use an indirection over an mpsc channel in
order to avoid deadlocks if we emit logs while holding the writer lock
on stdout.