Ensure delivery of bind success response before further messages sent

[github-actions]

• Keep a flag in @bindings hash, set the flag as success message has been sent
• Notify update gets subscription, checks @bindings for flag and waits on channel if not ready

rest-api/src/placeos-rest-api/websocket/session.cr

Lines 118 to 161 in aa815ec

	# Bind a websocket to a module subscription
	#
	def bind(
	request_id : Int64,
	system_id : String,
	module_name : String,
	index : Int32,
	name : String
	)
	Log.debug { "binding to module" }
	begin
	# Check if module previously bound
	unless has_binding?(system_id, module_name, index, name)
	return unless create_binding(request_id, system_id, module_name, index, name)
	end
	rescue error
	Log.warn(exception: error) { "websocket binding could not find system" }
	respond(error_response(request_id, :module_not_found, "could not find module: sys=#{system_id} mod=#{module_name}"))
	return
	end
	# Notify success
	# TODO: Ensure delivery of success before messages
	# - keep a flag in @bindings hash, set flag once success sent and send message on channel
	# - notify update gets subscription, checks binding hash for flag, otherwise wait on channel
	# Could use a promise
	response = Response.new(
	id: request_id,
	type: :success,
	metadata: {
	sys: system_id,
	mod: module_name,
	index: index,
	name: name,
	},
	)
	respond(response)
	rescue e
	Log.error(exception: e) { {
	message: "failed to bind",
	error: e.message,
	} }
	respond(error_response(request_id, :unexpected_failure, "failed to bind"))
	end