ruby-sigint ready to be merged!

8 files changed, 355 insertions, 2 deletions

diff --git a/examples/ruby/greeter_server.rb b/examples/ruby/greeter_server.rb
index dca61714b8..5290429742 100755
--- a/examples/ruby/greeter_server.rb
+++ b/examples/ruby/greeter_server.rb
@@ -39,7 +39,10 @@ def main
   s = GRPC::RpcServer.new
   s.add_http2_port('0.0.0.0:50051', :this_port_is_insecure)
   s.handle(GreeterServer)
-  s.run_till_terminated
+  # Runs the server with SIGHUP, SIGINT and SIGQUIT signal handlers to 
+  #   gracefully shutdown.
+  # User could also choose to run server via call to run_till_terminated
+  s.run_till_terminated_or_interrupted([1, 'int', 'SIGQUIT'])
 end
 
 main
diff --git a/examples/ruby/route_guide/route_guide_server.rb b/examples/ruby/route_guide/route_guide_server.rb
index 5eb268b533..ffcebd8418 100755
--- a/examples/ruby/route_guide/route_guide_server.rb
+++ b/examples/ruby/route_guide/route_guide_server.rb
@@ -172,7 +172,10 @@ def main
   s.add_http2_port(port, :this_port_is_insecure)
   GRPC.logger.info("... running insecurely on #{port}")
   s.handle(ServerImpl.new(feature_db))
-  s.run_till_terminated
+  # Runs the server with SIGHUP, SIGINT and SIGQUIT signal handlers to 
+  #   gracefully shutdown.
+  # User could also choose to run server via call to run_till_terminated
+  s.run_till_terminated_or_interrupted([1, 'int', 'SIGQUIT'])
 end
 
 main
diff --git a/src/ruby/end2end/graceful_sig_handling_client.rb b/src/ruby/end2end/graceful_sig_handling_client.rb
new file mode 100755
index 0000000000..14a67a62cc
--- /dev/null
+++ b/src/ruby/end2end/graceful_sig_handling_client.rb
@@ -0,0 +1,61 @@
+#!/usr/bin/env ruby
+
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require_relative './end2end_common'
+
+# Test client. Sends RPC's as normal but process also has signal handlers
+class SigHandlingClientController < ClientControl::ClientController::Service
+  def initialize(stub)
+    @stub = stub
+  end
+
+  def do_echo_rpc(req, _)
+    response = @stub.echo(Echo::EchoRequest.new(request: req.request))
+    fail 'bad response' unless response.response == req.request
+    ClientControl::Void.new
+  end
+end
+
+def main
+  client_control_port = ''
+  server_port = ''
+  OptionParser.new do |opts|
+    opts.on('--client_control_port=P', String) do |p|
+      client_control_port = p
+    end
+    opts.on('--server_port=P', String) do |p|
+      server_port = p
+    end
+  end.parse!
+
+  # Allow a few seconds to be safe.
+  srv = new_rpc_server_for_testing
+  srv.add_http2_port("0.0.0.0:#{client_control_port}",
+                     :this_port_is_insecure)
+  stub = Echo::EchoServer::Stub.new("localhost:#{server_port}",
+                                    :this_channel_is_insecure)
+  control_service = SigHandlingClientController.new(stub)
+  srv.handle(control_service)
+  server_thread = Thread.new do
+    srv.run_till_terminated_or_interrupted(['int'])
+  end
+  srv.wait_till_running
+  # send a first RPC to notify the parent process that we've started
+  stub.echo(Echo::EchoRequest.new(request: 'client/child started'))
+  server_thread.join
+end
+
+main
diff --git a/src/ruby/end2end/graceful_sig_handling_driver.rb b/src/ruby/end2end/graceful_sig_handling_driver.rb
new file mode 100755
index 0000000000..e12ae28485
--- /dev/null
+++ b/src/ruby/end2end/graceful_sig_handling_driver.rb
@@ -0,0 +1,83 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# smoke test for a grpc-using app that receives and
+# handles process-ending signals
+
+require_relative './end2end_common'
+
+# A service that calls back it's received_rpc_callback
+# upon receiving an RPC. Used for synchronization/waiting
+# for child process to start.
+class ClientStartedService < Echo::EchoServer::Service
+  def initialize(received_rpc_callback)
+    @received_rpc_callback = received_rpc_callback
+  end
+
+  def echo(echo_req, _)
+    @received_rpc_callback.call unless @received_rpc_callback.nil?
+    @received_rpc_callback = nil
+    Echo::EchoReply.new(response: echo_req.request)
+  end
+end
+
+def main
+  STDERR.puts 'start server'
+  client_started = false
+  client_started_mu = Mutex.new
+  client_started_cv = ConditionVariable.new
+  received_rpc_callback = proc do
+    client_started_mu.synchronize do
+      client_started = true
+      client_started_cv.signal
+    end
+  end
+
+  client_started_service = ClientStartedService.new(received_rpc_callback)
+  server_runner = ServerRunner.new(client_started_service)
+  server_port = server_runner.run
+  STDERR.puts 'start client'
+  control_stub, client_pid = start_client('graceful_sig_handling_client.rb', server_port)
+
+  client_started_mu.synchronize do
+    client_started_cv.wait(client_started_mu) until client_started
+  end
+
+  control_stub.do_echo_rpc(
+    ClientControl::DoEchoRpcRequest.new(request: 'hello'))
+
+  STDERR.puts 'killing client'
+  Process.kill('SIGINT', client_pid)
+  Process.wait(client_pid)
+  client_exit_status = $CHILD_STATUS
+
+  if client_exit_status.exited?
+    if client_exit_status.exitstatus != 0
+      STDERR.puts 'Client did not close gracefully'
+      exit(1)
+    end
+  else
+    STDERR.puts 'Client did not close gracefully'
+    exit(1)
+  end
+
+  STDERR.puts 'Client ended gracefully'
+
+  # no need to call cleanup, client should already be dead
+  server_runner.stop
+end
+
+main
diff --git a/src/ruby/end2end/graceful_sig_stop_client.rb b/src/ruby/end2end/graceful_sig_stop_client.rb
new file mode 100755
index 0000000000..b672dc3f2a
--- /dev/null
+++ b/src/ruby/end2end/graceful_sig_stop_client.rb
@@ -0,0 +1,78 @@
+#!/usr/bin/env ruby
+
+# Copyright 2015 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require_relative './end2end_common'
+
+# Test client. Sends RPC's as normal but process also has signal handlers
+class SigHandlingClientController < ClientControl::ClientController::Service
+  def initialize(srv, stub)
+    @srv = srv
+    @stub = stub
+  end
+
+  def do_echo_rpc(req, _)
+    response = @stub.echo(Echo::EchoRequest.new(request: req.request))
+    fail 'bad response' unless response.response == req.request
+    ClientControl::Void.new
+  end
+
+  def shutdown(_, _)
+    # Spawn a new thread because RpcServer#stop is
+    # synchronous and blocks until either this RPC has finished,
+    # or the server's "poll_period" seconds have passed.
+    @shutdown_thread = Thread.new do
+      @srv.stop
+    end
+    ClientControl::Void.new
+  end
+
+  def join_shutdown_thread
+    @shutdown_thread.join
+  end
+end
+
+def main
+  client_control_port = ''
+  server_port = ''
+  OptionParser.new do |opts|
+    opts.on('--client_control_port=P', String) do |p|
+      client_control_port = p
+    end
+    opts.on('--server_port=P', String) do |p|
+      server_port = p
+    end
+  end.parse!
+
+  # The "shutdown" RPC should end very quickly.
+  # Allow a few seconds to be safe.
+  srv = new_rpc_server_for_testing(poll_period: 3)
+  srv.add_http2_port("0.0.0.0:#{client_control_port}",
+                     :this_port_is_insecure)
+  stub = Echo::EchoServer::Stub.new("localhost:#{server_port}",
+                                    :this_channel_is_insecure)
+  control_service = SigHandlingClientController.new(srv, stub)
+  srv.handle(control_service)
+  server_thread = Thread.new do
+    srv.run_till_terminated_or_interrupted(['int'])
+  end
+  srv.wait_till_running
+  # send a first RPC to notify the parent process that we've started
+  stub.echo(Echo::EchoRequest.new(request: 'client/child started'))
+  server_thread.join
+  control_service.join_shutdown_thread
+end
+
+main
diff --git a/src/ruby/end2end/graceful_sig_stop_driver.rb b/src/ruby/end2end/graceful_sig_stop_driver.rb
new file mode 100755
index 0000000000..7a132403eb
--- /dev/null
+++ b/src/ruby/end2end/graceful_sig_stop_driver.rb
@@ -0,0 +1,62 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016 gRPC authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# smoke test for a grpc-using app that receives and
+# handles process-ending signals
+
+require_relative './end2end_common'
+
+# A service that calls back it's received_rpc_callback
+# upon receiving an RPC. Used for synchronization/waiting
+# for child process to start.
+class ClientStartedService < Echo::EchoServer::Service
+  def initialize(received_rpc_callback)
+    @received_rpc_callback = received_rpc_callback
+  end
+
+  def echo(echo_req, _)
+    @received_rpc_callback.call unless @received_rpc_callback.nil?
+    @received_rpc_callback = nil
+    Echo::EchoReply.new(response: echo_req.request)
+  end
+end
+
+def main
+  STDERR.puts 'start server'
+  client_started = false
+  client_started_mu = Mutex.new
+  client_started_cv = ConditionVariable.new
+  received_rpc_callback = proc do
+    client_started_mu.synchronize do
+      client_started = true
+      client_started_cv.signal
+    end
+  end
+
+  client_started_service = ClientStartedService.new(received_rpc_callback)
+  server_runner = ServerRunner.new(client_started_service)
+  server_port = server_runner.run
+  STDERR.puts 'start client'
+  control_stub, client_pid = start_client('./graceful_sig_stop_client.rb', server_port)
+
+  client_started_mu.synchronize do
+    client_started_cv.wait(client_started_mu) until client_started
+  end
+
+  cleanup(control_stub, client_pid, server_runner)
+end
+
+main
diff --git a/src/ruby/lib/grpc/generic/rpc_server.rb b/src/ruby/lib/grpc/generic/rpc_server.rb
index 3b5a0ce27f..f0f73dc56e 100644
--- a/src/ruby/lib/grpc/generic/rpc_server.rb
+++ b/src/ruby/lib/grpc/generic/rpc_server.rb
@@ -240,6 +240,13 @@ module GRPC
     # the call has no impact if the server is already stopped, otherwise
     # server's current call loop is it's last.
     def stop
+      # if called via run_till_terminated_or_interrupted,
+      #   signal stop_server_thread and dont do anything
+      if @stop_server.nil? == false && @stop_server == false
+        @stop_server = true
+        @stop_server_cv.broadcast
+        return
+      end
       @run_mutex.synchronize do
         fail 'Cannot stop before starting' if @running_state == :not_started
         return if @running_state != :running
@@ -354,6 +361,60 @@ module GRPC
 
     alias_method :run_till_terminated, :run
 
+    # runs the server with signal handlers
+    # @param signals
+    #     List of String, Integer or both representing signals that the user
+    #     would like to send to the server for graceful shutdown
+    # @param wait_interval (optional)
+    #     Integer seconds that user would like stop_server_thread to poll
+    #     stop_server
+    def run_till_terminated_or_interrupted(signals, wait_interval = 60)
+      @stop_server = false
+      @stop_server_mu = Mutex.new
+      @stop_server_cv = ConditionVariable.new
+
+      @stop_server_thread = Thread.new do
+        loop do
+          break if @stop_server
+          @stop_server_mu.synchronize do
+            @stop_server_cv.wait(@stop_server_mu, wait_interval)
+          end
+        end
+
+        # stop is surrounded by mutex, should handle multiple calls to stop
+        #   correctly
+        stop
+      end
+
+      valid_signals = Signal.list
+
+      # register signal handlers
+      signals.each do |sig|
+        # input validation
+        if sig.class == String
+          sig.upcase!
+          if sig.start_with?('SIG')
+            # cut out the SIG prefix to see if valid signal
+            sig = sig[3..-1]
+          end
+        end
+
+        # register signal traps for all valid signals
+        if valid_signals.value?(sig) || valid_signals.key?(sig)
+          Signal.trap(sig) do
+            @stop_server = true
+            @stop_server_cv.broadcast
+          end
+        else
+          fail "#{sig} not a valid signal"
+        end
+      end
+
+      run
+
+      @stop_server_thread.join
+    end
+
     # Sends RESOURCE_EXHAUSTED if there are too many unprocessed jobs
     def available?(an_rpc)
       return an_rpc if @pool.ready_for_work?
diff --git a/tools/run_tests/helper_scripts/run_ruby_end2end_tests.sh b/tools/run_tests/helper_scripts/run_ruby_end2end_tests.sh
index 7ff877e830..1c48ed20ba 100755
--- a/tools/run_tests/helper_scripts/run_ruby_end2end_tests.sh
+++ b/tools/run_tests/helper_scripts/run_ruby_end2end_tests.sh
@@ -30,4 +30,6 @@ time ruby src/ruby/end2end/multiple_killed_watching_threads_driver.rb || EXIT_CO
 time ruby src/ruby/end2end/load_grpc_with_gc_stress_driver.rb || EXIT_CODE=1
 time ruby src/ruby/end2end/client_memory_usage_driver.rb || EXIT_CODE=1
 time ruby src/ruby/end2end/package_with_underscore_checker.rb || EXIT_CODE=1
+time ruby src/ruby/end2end/graceful_sig_handling_driver.rb || EXIT_CODE=1
+time ruby src/ruby/end2end/graceful_sig_stop_driver.rb || EXIT_CODE=1
 exit $EXIT_CODE