| # Copyright 2015, Google Inc. |
| # All rights reserved. |
| # |
| # Redistribution and use in source and binary forms, with or without |
| # modification, are permitted provided that the following conditions are |
| # met: |
| # |
| # * Redistributions of source code must retain the above copyright |
| # notice, this list of conditions and the following disclaimer. |
| # * Redistributions in binary form must reproduce the above |
| # copyright notice, this list of conditions and the following disclaimer |
| # in the documentation and/or other materials provided with the |
| # distribution. |
| # * Neither the name of Google Inc. nor the names of its |
| # contributors may be used to endorse or promote products derived from |
| # this software without specific prior written permission. |
| # |
| # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| require 'grpc/grpc' |
| |
| # GRPC contains the General RPC module. |
| module GRPC |
| # RpcDesc is a Descriptor of an RPC method. |
| class RpcDesc < Struct.new(:name, :input, :output, :marshal_method, |
| :unmarshal_method) |
| include Core::StatusCodes |
| |
| # Used to wrap a message class to indicate that it needs to be streamed. |
| class Stream |
| attr_accessor :type |
| |
| def initialize(type) |
| @type = type |
| end |
| end |
| |
| # @return [Proc] { |instance| marshalled(instance) } |
| def marshal_proc |
| proc { |o| o.class.method(marshal_method).call(o).to_s } |
| end |
| |
| # @param [:input, :output] target determines whether to produce the an |
| # unmarshal Proc for the rpc input parameter or |
| # its output parameter |
| # |
| # @return [Proc] An unmarshal proc { |marshalled(instance)| instance } |
| def unmarshal_proc(target) |
| fail ArgumentError unless [:input, :output].include?(target) |
| unmarshal_class = method(target).call |
| unmarshal_class = unmarshal_class.type if unmarshal_class.is_a? Stream |
| proc { |o| unmarshal_class.method(unmarshal_method).call(o) } |
| end |
| |
| def run_server_method(active_call, mth) |
| # While a server method is running, it might be cancelled, its deadline |
| # might be reached, the handler could throw an unknown error, or a |
| # well-behaved handler could throw a StatusError. |
| if request_response? |
| req = active_call.remote_read |
| resp = mth.call(req, active_call.single_req_view) |
| active_call.remote_send(resp) |
| elsif client_streamer? |
| resp = mth.call(active_call.multi_req_view) |
| active_call.remote_send(resp) |
| elsif server_streamer? |
| req = active_call.remote_read |
| replys = mth.call(req, active_call.single_req_view) |
| replys.each { |r| active_call.remote_send(r) } |
| else # is a bidi_stream |
| active_call.run_server_bidi(mth) |
| end |
| send_status(active_call, OK, 'OK') |
| rescue BadStatus => e |
| # this is raised by handlers that want GRPC to send an application |
| # error code and detail message. |
| logger.debug("app err: #{active_call}, status:#{e.code}:#{e.details}") |
| send_status(active_call, e.code, e.details) |
| rescue Core::CallError => e |
| # This is raised by GRPC internals but should rarely, if ever happen. |
| # Log it, but don't notify the other endpoint.. |
| logger.warn("failed call: #{active_call}\n#{e}") |
| rescue OutOfTime |
| # This is raised when active_call#method.call exceeeds the deadline |
| # event. Send a status of deadline exceeded |
| logger.warn("late call: #{active_call}") |
| send_status(active_call, DEADLINE_EXCEEDED, 'late') |
| rescue Core::EventError => e |
| # This is raised by GRPC internals but should rarely, if ever happen. |
| # Log it, but don't notify the other endpoint.. |
| logger.warn("failed call: #{active_call}\n#{e}") |
| rescue StandardError => e |
| # This will usuaally be an unhandled error in the handling code. |
| # Send back a UNKNOWN status to the client |
| logger.warn("failed handler: #{active_call}; sending status:UNKNOWN") |
| logger.warn(e) |
| send_status(active_call, UNKNOWN, 'no reason given') |
| end |
| |
| def assert_arity_matches(mth) |
| if request_response? || server_streamer? |
| if mth.arity != 2 |
| fail arity_error(mth, 2, "should be #{mth.name}(req, call)") |
| end |
| else |
| if mth.arity != 1 |
| fail arity_error(mth, 1, "should be #{mth.name}(call)") |
| end |
| end |
| end |
| |
| def request_response? |
| !input.is_a?(Stream) && !output.is_a?(Stream) |
| end |
| |
| def client_streamer? |
| input.is_a?(Stream) && !output.is_a?(Stream) |
| end |
| |
| def server_streamer? |
| !input.is_a?(Stream) && output.is_a?(Stream) |
| end |
| |
| def bidi_streamer? |
| input.is_a?(Stream) && output.is_a?(Stream) |
| end |
| |
| def arity_error(mth, want, msg) |
| "##{mth.name}: bad arg count; got:#{mth.arity}, want:#{want}, #{msg}" |
| end |
| |
| def send_status(active_client, code, details) |
| details = 'Not sure why' if details.nil? |
| active_client.send_status(code, details) |
| rescue StandardError => e |
| logger.warn("Could not send status #{code}:#{details}") |
| logger.warn(e) |
| end |
| end |
| end |