The old implementation slurped the whole artefact into memory, and
did not ensure it remained allocated beyond the first call to write().
The new implementation uses mmap and ensures the mapping lasts until
the file has been delivered
Now that capnp/kj provides http and websocket functions, replace
the excellent websocketpp library with the kj functions. This
removes a dependency and allows for more consistent idiomatic
code. Thanks websocketpp, it was great to have you along!
This should enable parts of the refactor described in #49
Now explicitly closed connections on the client side are
closed with a clean error code. This is motivated by upcoming
work to detect broken websockets and automatically reconnect
Improve the boundary between RpcImpl and LaminarInterface such
that the Laminar class doesn't require any types from kj/async.h.
The necessary logic moved from Laminar to RpcImpl and the notification
now happens by abstract virtual callback instead of kj::Promise.
Also remove the fairly useless 'wait' RPC call and drop the wrappers
around kj::PromiseFulfillerPair
Oliver Giles