Merge branch 'v1.2.x' of https://github.com/grpc/grpc into upmerge-1.2.0

21 files changed, 1379 insertions, 69 deletions

diff --git a/src/ruby/.rubocop.yml b/src/ruby/.rubocop.yml
index 0f61ccfa81..7174f3b15a 100644
--- a/src/ruby/.rubocop.yml
+++ b/src/ruby/.rubocop.yml
@@ -9,6 +9,7 @@ AllCops:
     - 'bin/math_services_pb.rb'
     - 'pb/grpc/health/v1/*'
     - 'pb/test/**/*'
+    - 'end2end/lib/*'
 
 Metrics/CyclomaticComplexity:
   Max: 9
diff --git a/src/ruby/end2end/README.md b/src/ruby/end2end/README.md
new file mode 100644
index 0000000000..ea5ab6d4bc
--- /dev/null
+++ b/src/ruby/end2end/README.md
@@ -0,0 +1,18 @@
+This directory contains some grpc-ruby end to end tests.
+
+Each test here involves two files: a "driver" and a "client". For example,
+the "channel_closing" test involves channel_closing_driver.rb
+and channel_closing_client.rb.
+
+Typically, the "driver" will start up a simple "echo" server, and then
+spawn a client. It gives the client the address of the "echo" server as
+well as an address to listen on for control rpcs. Depending on the test, the
+client usually starts up a "ClientControl" grpc server for the driver to
+interact with (the driver can tell the client process to do strange things at
+different times, depending on the test).
+
+So far these tests are mostly useful for testing process-shutdown related
+situations, since the client's run in separate processes.
+
+These tests are invoked through the "tools/run_tests/run_tests.py" script (the
+Rakefile doesn't start these).
diff --git a/src/ruby/end2end/channel_closing_client.rb b/src/ruby/end2end/channel_closing_client.rb
new file mode 100755
index 0000000000..8449797360
--- /dev/null
+++ b/src/ruby/end2end/channel_closing_client.rb
@@ -0,0 +1,84 @@
+#!/usr/bin/env ruby
+
+# 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_relative './end2end_common'
+
+# Calls '#close' on a Channel when "shutdown" called. This tries to
+# trigger a hang or crash bug by closing a channel actively being watched
+class ChannelClosingClientController < ClientControl::ClientController::Service
+  def initialize(ch)
+    @ch = ch
+  end
+
+  def shutdown(_, _)
+    @ch.close
+    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!
+
+  ch = GRPC::Core::Channel.new("localhost:#{server_port}", {},
+                               :this_channel_is_insecure)
+
+  srv = GRPC::RpcServer.new
+  thd = Thread.new do
+    srv.add_http2_port("0.0.0.0:#{client_control_port}", :this_port_is_insecure)
+    srv.handle(ChannelClosingClientController.new(ch))
+    srv.run
+  end
+
+  # this should break out with an exception once the channel is closed
+  loop do
+    begin
+      state = ch.connectivity_state(true)
+      ch.watch_connectivity_state(state, Time.now + 360)
+    rescue RuntimeError => e
+      STDERR.puts "(expected) error occurred: #{e.inspect}"
+      break
+    end
+  end
+
+  srv.stop
+  thd.join
+end
+
+main
diff --git a/src/ruby/end2end/channel_closing_driver.rb b/src/ruby/end2end/channel_closing_driver.rb
new file mode 100755
index 0000000000..43e2fe8cbb
--- /dev/null
+++ b/src/ruby/end2end/channel_closing_driver.rb
@@ -0,0 +1,67 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016, 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.
+
+# make sure that the client doesn't hang when channel is closed
+# explictly while it's used
+
+require_relative './end2end_common'
+
+def main
+  STDERR.puts 'start server'
+  server_runner = ServerRunner.new
+  server_port = server_runner.run
+
+  sleep 1
+
+  STDERR.puts 'start client'
+  control_stub, client_pid = start_client('channel_closing_client.rb',
+                                          server_port)
+
+  sleep 3
+
+  begin
+    Timeout.timeout(10) do
+      control_stub.shutdown(ClientControl::Void.new)
+      Process.wait(client_pid)
+    end
+  rescue Timeout::Error
+    STDERR.puts "timeout wait for client pid #{client_pid}"
+    Process.kill('SIGKILL', client_pid)
+    Process.wait(client_pid)
+    STDERR.puts 'killed client child'
+    raise 'Timed out waiting for client process. It likely hangs when a ' \
+      'channel is closed while connectivity is watched'
+  end
+
+  server_runner.stop
+end
+
+main
diff --git a/src/ruby/end2end/channel_state_client.rb b/src/ruby/end2end/channel_state_client.rb
new file mode 100755
index 0000000000..08c21bbb8e
--- /dev/null
+++ b/src/ruby/end2end/channel_state_client.rb
@@ -0,0 +1,54 @@
+#!/usr/bin/env ruby
+
+# 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_relative './end2end_common'
+
+def main
+  server_port = ''
+  OptionParser.new do |opts|
+    opts.on('--client_control_port=P', String) do
+      STDERR.puts 'client_control_port ignored'
+    end
+    opts.on('--server_port=P', String) do |p|
+      server_port = p
+    end
+  end.parse!
+
+  ch = GRPC::Core::Channel.new("localhost:#{server_port}", {},
+                               :this_channel_is_insecure)
+
+  loop do
+    state = ch.connectivity_state
+    ch.watch_connectivity_state(state, Time.now + 360)
+  end
+end
+
+main
diff --git a/src/ruby/end2end/channel_state_driver.rb b/src/ruby/end2end/channel_state_driver.rb
new file mode 100755
index 0000000000..c3184bf939
--- /dev/null
+++ b/src/ruby/end2end/channel_state_driver.rb
@@ -0,0 +1,64 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016, 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.
+
+# make sure that the client doesn't hang when process ended abruptly
+
+require_relative './end2end_common'
+
+def main
+  STDERR.puts 'start server'
+  server_runner = ServerRunner.new
+  server_port = server_runner.run
+
+  sleep 1
+
+  STDERR.puts 'start client'
+  _, client_pid = start_client('channel_state_client.rb', server_port)
+
+  sleep 3
+
+  Process.kill('SIGTERM', client_pid)
+
+  begin
+    Timeout.timeout(10) { Process.wait(client_pid) }
+  rescue Timeout::Error
+    STDERR.puts "timeout wait for client pid #{client_pid}"
+    Process.kill('SIGKILL', client_pid)
+    Process.wait(client_pid)
+    STDERR.puts 'killed client child'
+    raise 'Timed out waiting for client process. ' \
+           'It likely hangs when ended abruptly'
+  end
+
+  server_runner.stop
+end
+
+main
diff --git a/src/ruby/end2end/end2end_common.rb b/src/ruby/end2end/end2end_common.rb
new file mode 100755
index 0000000000..9534bb2078
--- /dev/null
+++ b/src/ruby/end2end/end2end_common.rb
@@ -0,0 +1,109 @@
+#!/usr/bin/env ruby
+
+# 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.
+
+this_dir = File.expand_path(File.dirname(__FILE__))
+protos_lib_dir = File.join(this_dir, 'lib')
+grpc_lib_dir = File.join(File.dirname(this_dir), 'lib')
+$LOAD_PATH.unshift(grpc_lib_dir) unless $LOAD_PATH.include?(grpc_lib_dir)
+$LOAD_PATH.unshift(protos_lib_dir) unless $LOAD_PATH.include?(protos_lib_dir)
+$LOAD_PATH.unshift(this_dir) unless $LOAD_PATH.include?(this_dir)
+
+require 'grpc'
+require 'echo_services_pb'
+require 'client_control_services_pb'
+require 'socket'
+require 'optparse'
+require 'thread'
+require 'timeout'
+require 'English' # see https://github.com/bbatsov/rubocop/issues/1747
+
+# GreeterServer is simple server that implements the Helloworld Greeter server.
+class EchoServerImpl < Echo::EchoServer::Service
+  # say_hello implements the SayHello rpc method.
+  def echo(echo_req, _)
+    Echo::EchoReply.new(response: echo_req.request)
+  end
+end
+
+# ServerRunner starts an "echo server" that test clients can make calls to
+class ServerRunner
+  def initialize
+  end
+
+  def run
+    @srv = GRPC::RpcServer.new
+    port = @srv.add_http2_port('0.0.0.0:0', :this_port_is_insecure)
+    @srv.handle(EchoServerImpl)
+
+    @thd = Thread.new do
+      @srv.run
+    end
+    @srv.wait_till_running
+    port
+  end
+
+  def stop
+    @srv.stop
+    @thd.join
+    fail 'server not stopped' unless @srv.stopped?
+  end
+end
+
+def start_client(client_main, server_port)
+  this_dir = File.expand_path(File.dirname(__FILE__))
+
+  tmp_server = TCPServer.new(0)
+  client_control_port = tmp_server.local_address.ip_port
+  tmp_server.close
+
+  client_path = File.join(this_dir, client_main)
+  client_pid = Process.spawn(RbConfig.ruby,
+                             client_path,
+                             "--client_control_port=#{client_control_port}",
+                             "--server_port=#{server_port}")
+  sleep 1
+  control_stub = ClientControl::ClientController::Stub.new(
+    "localhost:#{client_control_port}", :this_channel_is_insecure)
+  [control_stub, client_pid]
+end
+
+def cleanup(control_stub, client_pid, server_runner)
+  control_stub.shutdown(ClientControl::Void.new)
+  Process.wait(client_pid)
+
+  client_exit_code = $CHILD_STATUS
+
+  if client_exit_code != 0
+    fail "term sig test failure: client exit code: #{client_exit_code}"
+  end
+
+  server_runner.stop
+end
diff --git a/src/ruby/end2end/gen_protos.sh b/src/ruby/end2end/gen_protos.sh
new file mode 100644
index 0000000000..f78d9ad394
--- /dev/null
+++ b/src/ruby/end2end/gen_protos.sh
@@ -0,0 +1,32 @@
+#!/bin/bash
+
+# Copyright 2016, 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.
+
+grpc_tools_ruby_protoc -I protos --ruby_out=lib --grpc_out=lib protos/echo.proto protos/client_control.proto
diff --git a/src/ruby/end2end/lib/client_control_pb.rb b/src/ruby/end2end/lib/client_control_pb.rb
new file mode 100644
index 0000000000..1a938f1b5a
--- /dev/null
+++ b/src/ruby/end2end/lib/client_control_pb.rb
@@ -0,0 +1,17 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: client_control.proto
+
+require 'google/protobuf'
+
+Google::Protobuf::DescriptorPool.generated_pool.build do
+  add_message "client_control.DoEchoRpcRequest" do
+    optional :request, :string, 1
+  end
+  add_message "client_control.Void" do
+  end
+end
+
+module ClientControl
+  DoEchoRpcRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("client_control.DoEchoRpcRequest").msgclass
+  Void = Google::Protobuf::DescriptorPool.generated_pool.lookup("client_control.Void").msgclass
+end
diff --git a/src/ruby/end2end/lib/client_control_services_pb.rb b/src/ruby/end2end/lib/client_control_services_pb.rb
new file mode 100644
index 0000000000..04b2291bc7
--- /dev/null
+++ b/src/ruby/end2end/lib/client_control_services_pb.rb
@@ -0,0 +1,53 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# Source: client_control.proto for package 'client_control'
+# Original file comments:
+# 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'
+require 'client_control_pb'
+
+module ClientControl
+  module ClientController
+    class Service
+
+      include GRPC::GenericService
+
+      self.marshal_class_method = :encode
+      self.unmarshal_class_method = :decode
+      self.service_name = 'client_control.ClientController'
+
+      rpc :DoEchoRpc, DoEchoRpcRequest, Void
+      rpc :Shutdown, Void, Void
+    end
+
+    Stub = Service.rpc_stub_class
+  end
+end
diff --git a/src/ruby/end2end/lib/echo_pb.rb b/src/ruby/end2end/lib/echo_pb.rb
new file mode 100644
index 0000000000..c62adc0753
--- /dev/null
+++ b/src/ruby/end2end/lib/echo_pb.rb
@@ -0,0 +1,18 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: echo.proto
+
+require 'google/protobuf'
+
+Google::Protobuf::DescriptorPool.generated_pool.build do
+  add_message "echo.EchoRequest" do
+    optional :request, :string, 1
+  end
+  add_message "echo.EchoReply" do
+    optional :response, :string, 1
+  end
+end
+
+module Echo
+  EchoRequest = Google::Protobuf::DescriptorPool.generated_pool.lookup("echo.EchoRequest").msgclass
+  EchoReply = Google::Protobuf::DescriptorPool.generated_pool.lookup("echo.EchoReply").msgclass
+end
diff --git a/src/ruby/end2end/lib/echo_services_pb.rb b/src/ruby/end2end/lib/echo_services_pb.rb
new file mode 100644
index 0000000000..c66e975bf3
--- /dev/null
+++ b/src/ruby/end2end/lib/echo_services_pb.rb
@@ -0,0 +1,52 @@
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# Source: echo.proto for package 'echo'
+# Original file comments:
+# 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'
+require 'echo_pb'
+
+module Echo
+  module EchoServer
+    class Service
+
+      include GRPC::GenericService
+
+      self.marshal_class_method = :encode
+      self.unmarshal_class_method = :decode
+      self.service_name = 'echo.EchoServer'
+
+      rpc :Echo, EchoRequest, EchoReply
+    end
+
+    Stub = Service.rpc_stub_class
+  end
+end
diff --git a/src/ruby/end2end/protos/client_control.proto b/src/ruby/end2end/protos/client_control.proto
new file mode 100644
index 0000000000..f985bb486d
--- /dev/null
+++ b/src/ruby/end2end/protos/client_control.proto
@@ -0,0 +1,43 @@
+// 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.
+
+syntax = "proto3";
+
+package client_control;
+
+service ClientController {
+  rpc DoEchoRpc (DoEchoRpcRequest) returns (Void) {}
+  rpc Shutdown(Void) returns (Void) {}
+}
+
+message DoEchoRpcRequest {
+  string request = 1;
+}
+
+message Void{}
diff --git a/src/ruby/end2end/protos/echo.proto b/src/ruby/end2end/protos/echo.proto
new file mode 100644
index 0000000000..d47afef70f
--- /dev/null
+++ b/src/ruby/end2end/protos/echo.proto
@@ -0,0 +1,46 @@
+// 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.
+
+syntax = "proto3";
+
+package echo;
+
+service EchoServer {
+  rpc Echo (EchoRequest) returns (EchoReply) {}
+}
+
+// The request message containing the user's name.
+message EchoRequest {
+  string request = 1;
+}
+
+// The response message containing the greetings
+message EchoReply {
+  string response = 1;
+}
diff --git a/src/ruby/end2end/sig_handling_client.rb b/src/ruby/end2end/sig_handling_client.rb
new file mode 100755
index 0000000000..5b1e54718e
--- /dev/null
+++ b/src/ruby/end2end/sig_handling_client.rb
@@ -0,0 +1,89 @@
+#!/usr/bin/env ruby
+
+# 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_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(_, _)
+    Thread.new do
+      # TODO(apolcyn) There is a race between stopping the
+      # server and the "shutdown" rpc completing,
+      # See if stop method on server can end active RPC cleanly, to
+      # avoid this sleep.
+      sleep 3
+      @srv.stop
+    end
+    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!
+
+  Signal.trap('TERM') do
+    STDERR.puts 'SIGTERM received'
+  end
+
+  Signal.trap('INT') do
+    STDERR.puts 'SIGINT received'
+  end
+
+  srv = GRPC::RpcServer.new
+  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)
+  srv.handle(SigHandlingClientController.new(srv, stub))
+  srv.run
+end
+
+main
diff --git a/src/ruby/end2end/sig_handling_driver.rb b/src/ruby/end2end/sig_handling_driver.rb
new file mode 100755
index 0000000000..c5d46e074c
--- /dev/null
+++ b/src/ruby/end2end/sig_handling_driver.rb
@@ -0,0 +1,61 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016, 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.
+
+# smoke test for a grpc-using app that receives and
+# handles process-ending signals
+
+require_relative './end2end_common'
+
+def main
+  STDERR.puts 'start server'
+  server_runner = ServerRunner.new
+  server_port = server_runner.run
+
+  sleep 1
+
+  STDERR.puts 'start client'
+  control_stub, client_pid = start_client('sig_handling_client.rb', server_port)
+
+  sleep 1
+
+  count = 0
+  while count < 5
+    control_stub.do_echo_rpc(
+      ClientControl::DoEchoRpcRequest.new(request: 'hello'))
+    Process.kill('SIGTERM', client_pid)
+    Process.kill('SIGINT', client_pid)
+    count += 1
+  end
+
+  cleanup(control_stub, client_pid, server_runner)
+end
+
+main
diff --git a/src/ruby/end2end/sig_int_during_channel_watch_client.rb b/src/ruby/end2end/sig_int_during_channel_watch_client.rb
new file mode 100755
index 0000000000..389fc5ba33
--- /dev/null
+++ b/src/ruby/end2end/sig_int_during_channel_watch_client.rb
@@ -0,0 +1,70 @@
+#!/usr/bin/env ruby
+
+# 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_relative './end2end_common'
+
+# Start polling the channel state in both the main thread
+# and a child thread. Try to get the driver to send process-ending
+# interrupt while both a child thread and the main thread are in the
+# middle of a blocking connectivity_state call.
+def main
+  server_port = ''
+  OptionParser.new do |opts|
+    opts.on('--client_control_port=P', String) do
+      STDERR.puts 'client_control_port not used'
+    end
+    opts.on('--server_port=P', String) do |p|
+      server_port = p
+    end
+  end.parse!
+
+  thd = Thread.new do
+    child_thread_channel = GRPC::Core::Channel.new("localhost:#{server_port}",
+                                                   {},
+                                                   :this_channel_is_insecure)
+    loop do
+      state = child_thread_channel.connectivity_state(false)
+      child_thread_channel.watch_connectivity_state(state, Time.now + 360)
+    end
+  end
+
+  main_channel = GRPC::Core::Channel.new("localhost:#{server_port}",
+                                         {},
+                                         :this_channel_is_insecure)
+  loop do
+    state = main_channel.connectivity_state(false)
+    main_channel.watch_connectivity_state(state, Time.now + 360)
+  end
+
+  thd.join
+end
+
+main
diff --git a/src/ruby/end2end/sig_int_during_channel_watch_driver.rb b/src/ruby/end2end/sig_int_during_channel_watch_driver.rb
new file mode 100755
index 0000000000..84d039bf19
--- /dev/null
+++ b/src/ruby/end2end/sig_int_during_channel_watch_driver.rb
@@ -0,0 +1,69 @@
+#!/usr/bin/env ruby
+
+# Copyright 2016, 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.
+
+# abruptly end a process that has active calls to
+# Channel.watch_connectivity_state
+
+require_relative './end2end_common'
+
+def main
+  STDERR.puts 'start server'
+  server_runner = ServerRunner.new
+  server_port = server_runner.run
+
+  sleep 1
+
+  STDERR.puts 'start client'
+  _, client_pid = start_client('sig_int_during_channel_watch_client.rb',
+                               server_port)
+
+  # give time for the client to get into the middle
+  # of a channel state watch call
+  sleep 1
+  Process.kill('SIGINT', client_pid)
+
+  begin
+    Timeout.timeout(10) do
+      Process.wait(client_pid)
+    end
+  rescue Timeout::Error
+    STDERR.puts "timeout wait for client pid #{client_pid}"
+    Process.kill('SIGKILL', client_pid)
+    Process.wait(client_pid)
+    STDERR.puts 'killed client child'
+    raise 'Timed out waiting for client process. It likely hangs when a ' \
+      'SIGINT is sent while there is an active connectivity_state call'
+  end
+
+  server_runner.stop
+end
+
+main
diff --git a/src/ruby/ext/grpc/rb_channel.c b/src/ruby/ext/grpc/rb_channel.c
index 84e43d3f7b..1c20c8813f 100644
--- a/src/ruby/ext/grpc/rb_channel.c
+++ b/src/ruby/ext/grpc/rb_channel.c
@@ -32,21 +32,22 @@
  */
 
 #include <ruby/ruby.h>
+#include <ruby/thread.h>
 
 #include "rb_grpc_imports.generated.h"
-#include "rb_channel.h"
 #include "rb_byte_buffer.h"
+#include "rb_channel.h"
 
 #include <grpc/grpc.h>
 #include <grpc/grpc_security.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 #include <grpc/support/time.h>
-#include "rb_grpc.h"
 #include "rb_call.h"
 #include "rb_channel_args.h"
 #include "rb_channel_credentials.h"
 #include "rb_completion_queue.h"
+#include "rb_grpc.h"
 #include "rb_server.h"
 
 /* id_channel is the name of the hidden ivar that preserves a reference to the
@@ -73,9 +74,26 @@ typedef struct grpc_rb_channel {
 
   /* The actual channel */
   grpc_channel *wrapped;
-  grpc_completion_queue *queue;
+  int request_safe_destroy;
+  int safe_to_destroy;
+  grpc_connectivity_state current_connectivity_state;
+
+  int mu_init_done;
+  int abort_watch_connectivity_state;
+  gpr_mu channel_mu;
+  gpr_cv channel_cv;
 } grpc_rb_channel;
 
+/* Forward declarations of functions involved in temporary fix to
+ * https://github.com/grpc/grpc/issues/9941 */
+static void grpc_rb_channel_try_register_connection_polling(
+    grpc_rb_channel *wrapper);
+static void grpc_rb_channel_safe_destroy(grpc_rb_channel *wrapper);
+
+static grpc_completion_queue *channel_polling_cq;
+static gpr_mu global_connection_polling_mu;
+static int abort_channel_polling = 0;
+
 /* Destroys Channel instances. */
 static void grpc_rb_channel_free(void *p) {
   grpc_rb_channel *ch = NULL;
@@ -85,8 +103,13 @@ static void grpc_rb_channel_free(void *p) {
   ch = (grpc_rb_channel *)p;
 
   if (ch->wrapped != NULL) {
-    grpc_channel_destroy(ch->wrapped);
-    grpc_rb_completion_queue_destroy(ch->queue);
+    grpc_rb_channel_safe_destroy(ch);
+    ch->wrapped = NULL;
+  }
+
+  if (ch->mu_init_done) {
+    gpr_mu_destroy(&ch->channel_mu);
+    gpr_cv_destroy(&ch->channel_cv);
   }
 
   xfree(p);
@@ -104,13 +127,15 @@ static void grpc_rb_channel_mark(void *p) {
   }
 }
 
-static rb_data_type_t grpc_channel_data_type = {
-    "grpc_channel",
-    {grpc_rb_channel_mark, grpc_rb_channel_free, GRPC_RB_MEMSIZE_UNAVAILABLE,
-     {NULL, NULL}},
-    NULL, NULL,
+static rb_data_type_t grpc_channel_data_type = {"grpc_channel",
+                                                {grpc_rb_channel_mark,
+                                                 grpc_rb_channel_free,
+                                                 GRPC_RB_MEMSIZE_UNAVAILABLE,
+                                                 {NULL, NULL}},
+                                                NULL,
+                                                NULL,
 #ifdef RUBY_TYPED_FREE_IMMEDIATELY
-    RUBY_TYPED_FREE_IMMEDIATELY
+                                                RUBY_TYPED_FREE_IMMEDIATELY
 #endif
 };
 
@@ -145,6 +170,7 @@ static VALUE grpc_rb_channel_init(int argc, VALUE *argv, VALUE self) {
   rb_scan_args(argc, argv, "3", &target, &channel_args, &credentials);
 
   TypedData_Get_Struct(self, grpc_rb_channel, &grpc_channel_data_type, wrapper);
+  wrapper->mu_init_done = 0;
   target_chars = StringValueCStr(target);
   grpc_rb_hash_convert_to_channel_args(channel_args, &args);
   if (TYPE(credentials) == T_SYMBOL) {
@@ -159,6 +185,27 @@ static VALUE grpc_rb_channel_init(int argc, VALUE *argv, VALUE self) {
     creds = grpc_rb_get_wrapped_channel_credentials(credentials);
     ch = grpc_secure_channel_create(creds, target_chars, &args, NULL);
   }
+
+  GPR_ASSERT(ch);
+
+  wrapper->wrapped = ch;
+
+  gpr_mu_init(&wrapper->channel_mu);
+  gpr_cv_init(&wrapper->channel_cv);
+  wrapper->mu_init_done = 1;
+
+  gpr_mu_lock(&wrapper->channel_mu);
+  wrapper->abort_watch_connectivity_state = 0;
+  wrapper->current_connectivity_state = grpc_channel_check_connectivity_state(wrapper->wrapped, 0);
+  wrapper->safe_to_destroy = 0;
+  wrapper->request_safe_destroy = 0;
+
+  gpr_cv_broadcast(&wrapper->channel_cv);
+  gpr_mu_unlock(&wrapper->channel_mu);
+
+
+  grpc_rb_channel_try_register_connection_polling(wrapper);
+
   if (args.args != NULL) {
     xfree(args.args); /* Allocated by grpc_rb_hash_convert_to_channel_args */
   }
@@ -169,25 +216,28 @@ static VALUE grpc_rb_channel_init(int argc, VALUE *argv, VALUE self) {
   }
   rb_ivar_set(self, id_target, target);
   wrapper->wrapped = ch;
-  wrapper->queue = grpc_completion_queue_create(NULL);
   return self;
 }
 
 /*
   call-seq:
-    insecure_channel = Channel:new("myhost:8080", {'arg1': 'value1'})
-    creds = ...
-    secure_channel = Channel:new("myhost:443", {'arg1': 'value1'}, creds)
+    ch.connectivity_state       -> state
+    ch.connectivity_state(true) -> state
 
-  Creates channel instances. */
+  Indicates the current state of the channel, whose value is one of the
+  constants defined in GRPC::Core::ConnectivityStates.
+
+  It also tries to connect if the chennel is idle in the second form. */
 static VALUE grpc_rb_channel_get_connectivity_state(int argc, VALUE *argv,
                                                     VALUE self) {
-  VALUE try_to_connect = Qfalse;
+  VALUE try_to_connect_param = Qfalse;
+  int grpc_try_to_connect = 0;
   grpc_rb_channel *wrapper = NULL;
   grpc_channel *ch = NULL;
 
   /* "01" == 0 mandatory args, 1 (try_to_connect) is optional */
-  rb_scan_args(argc, argv, "01", try_to_connect);
+  rb_scan_args(argc, argv, "01", &try_to_connect_param);
+  grpc_try_to_connect = RTEST(try_to_connect_param) ? 1 : 0;
 
   TypedData_Get_Struct(self, grpc_rb_channel, &grpc_channel_data_type, wrapper);
   ch = wrapper->wrapped;
@@ -195,57 +245,88 @@ static VALUE grpc_rb_channel_get_connectivity_state(int argc, VALUE *argv,
     rb_raise(rb_eRuntimeError, "closed!");
     return Qnil;
   }
-  return NUM2LONG(
-      grpc_channel_check_connectivity_state(ch, (int)try_to_connect));
+  return LONG2NUM(grpc_channel_check_connectivity_state(wrapper->wrapped, grpc_try_to_connect));
 }
 
-/* Watch for a change in connectivity state.
+typedef struct watch_state_stack {
+  grpc_rb_channel *wrapper;
+  gpr_timespec deadline;
+  int last_state;
+} watch_state_stack;
+
+static void *watch_channel_state_without_gvl(void *arg) {
+  watch_state_stack *stack = (watch_state_stack*)arg;
+  gpr_timespec deadline = stack->deadline;
+  grpc_rb_channel *wrapper = stack->wrapper;
+  int last_state = stack->last_state;
+  void *return_value = (void*)0;
+
+  gpr_mu_lock(&wrapper->channel_mu);
+  while(wrapper->current_connectivity_state == last_state &&
+        !wrapper->request_safe_destroy &&
+        !wrapper->safe_to_destroy &&
+        !wrapper->abort_watch_connectivity_state &&
+        gpr_time_cmp(deadline, gpr_now(GPR_CLOCK_REALTIME)) > 0) {
+    gpr_cv_wait(&wrapper->channel_cv, &wrapper->channel_mu, deadline);
+  }
+  if (wrapper->current_connectivity_state != last_state) {
+    return_value = (void*)1;
+  }
+  gpr_mu_unlock(&wrapper->channel_mu);
+
+  return return_value;
+}
 
-   Once the channel connectivity state is different from the last observed
-   state, tag will be enqueued on cq with success=1
+static void watch_channel_state_unblocking_func(void *arg) {
+  grpc_rb_channel *wrapper = (grpc_rb_channel*)arg;
+  gpr_log(GPR_DEBUG, "GRPC_RUBY: watch channel state unblocking func called");
+  gpr_mu_lock(&wrapper->channel_mu);
+  wrapper->abort_watch_connectivity_state = 1;
+  gpr_cv_broadcast(&wrapper->channel_cv);
+  gpr_mu_unlock(&wrapper->channel_mu);
+}
 
-   If deadline expires BEFORE the state is changed, tag will be enqueued on
-   the completion queue with success=0 */
+/* Wait until the channel's connectivity state becomes different from
+ * "last_state", or "deadline" expires.
+ * Returns true if the the channel's connectivity state becomes
+ * different from "last_state" within "deadline".
+ * Returns false if "deadline" expires before the channel's connectivity
+ * state changes from "last_state".
+ * */
 static VALUE grpc_rb_channel_watch_connectivity_state(VALUE self,
                                                       VALUE last_state,
                                                       VALUE deadline) {
   grpc_rb_channel *wrapper = NULL;
-  grpc_channel *ch = NULL;
-  grpc_completion_queue *cq = NULL;
-
-  void *tag = wrapper;
-
-  grpc_event event;
+  watch_state_stack stack;
+  void* out;
 
   TypedData_Get_Struct(self, grpc_rb_channel, &grpc_channel_data_type, wrapper);
-  ch = wrapper->wrapped;
-  cq = wrapper->queue;
-  if (ch == NULL) {
+
+  if (wrapper->wrapped == NULL) {
     rb_raise(rb_eRuntimeError, "closed!");
     return Qnil;
   }
-  grpc_channel_watch_connectivity_state(
-      ch,
-      (grpc_connectivity_state)NUM2LONG(last_state),
-      grpc_rb_time_timeval(deadline, /* absolute time */ 0),
-      cq,
-      tag);
 
-  event = rb_completion_queue_pluck(cq, tag,
-                                    gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
+  if (!FIXNUM_P(last_state)) {
+    rb_raise(rb_eTypeError, "bad type for last_state. want a GRPC::Core::ChannelState constant");
+    return Qnil;
+  }
 
-  if (event.success) {
+  stack.wrapper = wrapper;
+  stack.deadline = grpc_rb_time_timeval(deadline, 0);
+  stack.last_state = NUM2LONG(last_state);
+  out = rb_thread_call_without_gvl(watch_channel_state_without_gvl, &stack, watch_channel_state_unblocking_func, wrapper);
+  if (out) {
     return Qtrue;
-  } else {
-    return Qfalse;
   }
+  return Qfalse;
 }
 
 /* Create a call given a grpc_channel, in order to call method. The request
    is not sent until grpc_call_invoke is called. */
-static VALUE grpc_rb_channel_create_call(VALUE self, VALUE parent,
-                                         VALUE mask, VALUE method,
-                                         VALUE host, VALUE deadline) {
+static VALUE grpc_rb_channel_create_call(VALUE self, VALUE parent, VALUE mask,
+                                         VALUE method, VALUE host,
+                                         VALUE deadline) {
   VALUE res = Qnil;
   grpc_rb_channel *wrapper = NULL;
   grpc_call *call = NULL;
@@ -256,10 +337,11 @@ static VALUE grpc_rb_channel_create_call(VALUE self, VALUE parent,
   grpc_slice method_slice;
   grpc_slice host_slice;
   grpc_slice *host_slice_ptr = NULL;
-  char* tmp_str = NULL;
+  char *tmp_str = NULL;
 
   if (host != Qnil) {
-    host_slice = grpc_slice_from_copied_buffer(RSTRING_PTR(host), RSTRING_LEN(host));
+    host_slice =
+        grpc_slice_from_copied_buffer(RSTRING_PTR(host), RSTRING_LEN(host));
     host_slice_ptr = &host_slice;
   }
   if (mask != Qnil) {
@@ -277,17 +359,18 @@ static VALUE grpc_rb_channel_create_call(VALUE self, VALUE parent,
     return Qnil;
   }
 
-  method_slice = grpc_slice_from_copied_buffer(RSTRING_PTR(method), RSTRING_LEN(method));
+  method_slice =
+      grpc_slice_from_copied_buffer(RSTRING_PTR(method), RSTRING_LEN(method));
 
   call = grpc_channel_create_call(ch, parent_call, flags, cq, method_slice,
-                                  host_slice_ptr, grpc_rb_time_timeval(
-                                      deadline,
-                                      /* absolute time */ 0), NULL);
+                                  host_slice_ptr,
+                                  grpc_rb_time_timeval(deadline,
+                                                       /* absolute time */ 0),
+                                  NULL);
 
   if (call == NULL) {
     tmp_str = grpc_slice_to_c_string(method_slice);
-    rb_raise(rb_eRuntimeError, "cannot create call with method %s",
-             tmp_str);
+    rb_raise(rb_eRuntimeError, "cannot create call with method %s", tmp_str);
     return Qnil;
   }
 
@@ -304,7 +387,6 @@ static VALUE grpc_rb_channel_create_call(VALUE self, VALUE parent,
   return res;
 }
 
-
 /* Closes the channel, calling it's destroy method */
 static VALUE grpc_rb_channel_destroy(VALUE self) {
   grpc_rb_channel *wrapper = NULL;
@@ -313,19 +395,18 @@ static VALUE grpc_rb_channel_destroy(VALUE self) {
   TypedData_Get_Struct(self, grpc_rb_channel, &grpc_channel_data_type, wrapper);
   ch = wrapper->wrapped;
   if (ch != NULL) {
-    grpc_channel_destroy(ch);
+    grpc_rb_channel_safe_destroy(wrapper);
     wrapper->wrapped = NULL;
   }
 
   return Qnil;
 }
 
-
 /* Called to obtain the target that this channel accesses. */
 static VALUE grpc_rb_channel_get_target(VALUE self) {
   grpc_rb_channel *wrapper = NULL;
   VALUE res = Qnil;
-  char* target = NULL;
+  char *target = NULL;
 
   TypedData_Get_Struct(self, grpc_rb_channel, &grpc_channel_data_type, wrapper);
   target = grpc_channel_get_target(wrapper->wrapped);
@@ -335,10 +416,122 @@ static VALUE grpc_rb_channel_get_target(VALUE self) {
   return res;
 }
 
+// Either start polling channel connection state or signal that it's free to
+// destroy.
+// Not safe to call while a channel's connection state is polled.
+static void grpc_rb_channel_try_register_connection_polling(
+  grpc_rb_channel *wrapper) {
+  grpc_connectivity_state conn_state;
+  gpr_timespec sleep_time = gpr_time_add(
+      gpr_now(GPR_CLOCK_REALTIME), gpr_time_from_millis(20, GPR_TIMESPAN));
+
+  GPR_ASSERT(wrapper);
+  GPR_ASSERT(wrapper->wrapped);
+  gpr_mu_lock(&wrapper->channel_mu);
+  if (wrapper->request_safe_destroy) {
+    wrapper->safe_to_destroy = 1;
+    gpr_cv_broadcast(&wrapper->channel_cv);
+    gpr_mu_unlock(&wrapper->channel_mu);
+    return;
+  }
+  gpr_mu_lock(&global_connection_polling_mu);
+
+  conn_state = grpc_channel_check_connectivity_state(wrapper->wrapped, 0);
+  if (conn_state != wrapper->current_connectivity_state) {
+    wrapper->current_connectivity_state = conn_state;
+    gpr_cv_broadcast(&wrapper->channel_cv);
+  }
+  // avoid posting work to the channel polling cq if it's been shutdown
+  if (!abort_channel_polling && conn_state != GRPC_CHANNEL_SHUTDOWN) {
+    grpc_channel_watch_connectivity_state(
+        wrapper->wrapped, conn_state, sleep_time, channel_polling_cq, wrapper);
+  } else {
+    wrapper->safe_to_destroy = 1;
+    gpr_cv_broadcast(&wrapper->channel_cv);
+  }
+  gpr_mu_unlock(&global_connection_polling_mu);
+  gpr_mu_unlock(&wrapper->channel_mu);
+}
+
+// Note requires wrapper->wrapped, wrapper->channel_mu/cv initialized
+static void grpc_rb_channel_safe_destroy(grpc_rb_channel *wrapper) {
+  gpr_mu_lock(&wrapper->channel_mu);
+  wrapper->request_safe_destroy = 1;
+
+  while (!wrapper->safe_to_destroy) {
+    gpr_cv_wait(&wrapper->channel_cv, &wrapper->channel_mu,
+                gpr_inf_future(GPR_CLOCK_REALTIME));
+  }
+  GPR_ASSERT(wrapper->safe_to_destroy);
+  gpr_mu_unlock(&wrapper->channel_mu);
+
+  grpc_channel_destroy(wrapper->wrapped);
+}
+
+// Note this loop breaks out with a single call of
+// "grpc_rb_event_unblocking_func".
+// This assumes that a ruby call the unblocking func
+// indicates process shutdown.
+// In the worst case, this stops polling channel connectivity
+// early and falls back to current behavior.
+static void *run_poll_channels_loop_no_gil(void *arg) {
+  grpc_event event;
+  (void)arg;
+  for (;;) {
+    event = grpc_completion_queue_next(
+        channel_polling_cq, gpr_inf_future(GPR_CLOCK_REALTIME), NULL);
+    if (event.type == GRPC_QUEUE_SHUTDOWN) {
+      break;
+    }
+    if (event.type == GRPC_OP_COMPLETE) {
+      grpc_rb_channel_try_register_connection_polling((grpc_rb_channel *)event.tag);
+    }
+  }
+  grpc_completion_queue_destroy(channel_polling_cq);
+  gpr_log(GPR_DEBUG, "GRPC_RUBY: run_poll_channels_loop_no_gil - exit connection polling loop");
+  return NULL;
+}
+
+// Notify the channel polling loop to cleanup and shutdown.
+static void grpc_rb_event_unblocking_func(void *arg) {
+  (void)arg;
+  gpr_mu_lock(&global_connection_polling_mu);
+  gpr_log(GPR_DEBUG, "GRPC_RUBY: grpc_rb_event_unblocking_func - begin aborting connection polling");
+  abort_channel_polling = 1;
+  grpc_completion_queue_shutdown(channel_polling_cq);
+  gpr_mu_unlock(&global_connection_polling_mu);
+}
+
+// Poll channel connectivity states in background thread without the GIL.
+static VALUE run_poll_channels_loop(VALUE arg) {
+  (void)arg;
+  gpr_log(GPR_DEBUG, "GRPC_RUBY: run_poll_channels_loop - create connection polling thread");
+  rb_thread_call_without_gvl(run_poll_channels_loop_no_gil, NULL,
+                             grpc_rb_event_unblocking_func, NULL);
+  return Qnil;
+}
+
+/* Temporary fix for
+ * https://github.com/GoogleCloudPlatform/google-cloud-ruby/issues/899.
+ * Transports in idle channels can get destroyed. Normally c-core re-connects,
+ * but in grpc-ruby core never gets a thread until an RPC is made, because ruby
+ * only calls c-core's "completion_queu_pluck" API.
+ * This uses a global background thread that calls
+ * "completion_queue_next" on registered "watch_channel_connectivity_state"
+ * calls - so that c-core can reconnect if needed, when there aren't any RPC's.
+ * TODO(apolcyn) remove this when core handles new RPCs on dead connections.
+ */
+static void start_poll_channels_loop() {
+  channel_polling_cq = grpc_completion_queue_create(NULL);
+  gpr_mu_init(&global_connection_polling_mu);
+  abort_channel_polling = 0;
+  rb_thread_create(run_poll_channels_loop, NULL);
+}
+
 static void Init_grpc_propagate_masks() {
   /* Constants representing call propagation masks in grpc.h */
-  VALUE grpc_rb_mPropagateMasks = rb_define_module_under(
-      grpc_rb_mGrpcCore, "PropagateMasks");
+  VALUE grpc_rb_mPropagateMasks =
+      rb_define_module_under(grpc_rb_mGrpcCore, "PropagateMasks");
   rb_define_const(grpc_rb_mPropagateMasks, "DEADLINE",
                   UINT2NUM(GRPC_PROPAGATE_DEADLINE));
   rb_define_const(grpc_rb_mPropagateMasks, "CENSUS_STATS_CONTEXT",
@@ -353,8 +546,8 @@ static void Init_grpc_propagate_masks() {
 
 static void Init_grpc_connectivity_states() {
   /* Constants representing call propagation masks in grpc.h */
-  VALUE grpc_rb_mConnectivityStates = rb_define_module_under(
-      grpc_rb_mGrpcCore, "ConnectivityStates");
+  VALUE grpc_rb_mConnectivityStates =
+      rb_define_module_under(grpc_rb_mGrpcCore, "ConnectivityStates");
   rb_define_const(grpc_rb_mConnectivityStates, "IDLE",
                   LONG2NUM(GRPC_CHANNEL_IDLE));
   rb_define_const(grpc_rb_mConnectivityStates, "CONNECTING",
@@ -382,12 +575,11 @@ void Init_grpc_channel() {
 
   /* Add ruby analogues of the Channel methods. */
   rb_define_method(grpc_rb_cChannel, "connectivity_state",
-                   grpc_rb_channel_get_connectivity_state,
-                   -1);
+                   grpc_rb_channel_get_connectivity_state, -1);
   rb_define_method(grpc_rb_cChannel, "watch_connectivity_state",
-                   grpc_rb_channel_watch_connectivity_state, 4);
-  rb_define_method(grpc_rb_cChannel, "create_call",
-                   grpc_rb_channel_create_call, 5);
+                   grpc_rb_channel_watch_connectivity_state, 2);
+  rb_define_method(grpc_rb_cChannel, "create_call", grpc_rb_channel_create_call,
+                   5);
   rb_define_method(grpc_rb_cChannel, "target", grpc_rb_channel_get_target, 0);
   rb_define_method(grpc_rb_cChannel, "destroy", grpc_rb_channel_destroy, 0);
   rb_define_alias(grpc_rb_cChannel, "close", "destroy");
@@ -405,6 +597,7 @@ void Init_grpc_channel() {
   id_insecure_channel = rb_intern("this_channel_is_insecure");
   Init_grpc_propagate_masks();
   Init_grpc_connectivity_states();
+  start_poll_channels_loop();
 }
 
 /* Gets the wrapped channel from the ruby wrapper */
diff --git a/src/ruby/spec/channel_connection_spec.rb b/src/ruby/spec/channel_connection_spec.rb
new file mode 100644
index 0000000000..940d68b9b0
--- /dev/null
+++ b/src/ruby/spec/channel_connection_spec.rb
@@ -0,0 +1,141 @@
+# 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'
+
+# A test message
+class EchoMsg
+  def self.marshal(_o)
+    ''
+  end
+
+  def self.unmarshal(_o)
+    EchoMsg.new
+  end
+end
+
+# A test service with an echo implementation.
+class EchoService
+  include GRPC::GenericService
+  rpc :an_rpc, EchoMsg, EchoMsg
+  attr_reader :received_md
+
+  def initialize(**kw)
+    @trailing_metadata = kw
+    @received_md = []
+  end
+
+  def an_rpc(req, call)
+    GRPC.logger.info('echo service received a request')
+    call.output_metadata.update(@trailing_metadata)
+    @received_md << call.metadata unless call.metadata.nil?
+    req
+  end
+end
+
+EchoStub = EchoService.rpc_stub_class
+
+def start_server(port = 0)
+  @srv = GRPC::RpcServer.new
+  server_port = @srv.add_http2_port("localhost:#{port}", :this_port_is_insecure)
+  @srv.handle(EchoService)
+  @server_thd = Thread.new { @srv.run }
+  @srv.wait_till_running
+  server_port
+end
+
+def stop_server
+  expect(@srv.stopped?).to be(false)
+  @srv.stop
+  @server_thd.join
+  expect(@srv.stopped?).to be(true)
+end
+
+describe 'channel connection behavior' do
+  it 'the client channel handles temporary loss of a transport' do
+    port = start_server
+    stub = EchoStub.new("localhost:#{port}", :this_channel_is_insecure)
+    req = EchoMsg.new
+    expect(stub.an_rpc(req)).to be_a(EchoMsg)
+    stop_server
+    sleep 1
+    # TODO(apolcyn) grabbing the same port might fail, is this stable enough?
+    start_server(port)
+    expect(stub.an_rpc(req)).to be_a(EchoMsg)
+    stop_server
+  end
+
+  it 'observably connects and reconnects to transient server' \
+    ' when using the channel state API' do
+    port = start_server
+    ch = GRPC::Core::Channel.new("localhost:#{port}", {},
+                                 :this_channel_is_insecure)
+
+    expect(ch.connectivity_state).to be(GRPC::Core::ConnectivityStates::IDLE)
+
+    state = ch.connectivity_state(true)
+
+    count = 0
+    while count < 20 && state != GRPC::Core::ConnectivityStates::READY
+      ch.watch_connectivity_state(state, Time.now + 60)
+      state = ch.connectivity_state(true)
+      count += 1
+    end
+
+    expect(state).to be(GRPC::Core::ConnectivityStates::READY)
+
+    stop_server
+
+    state = ch.connectivity_state
+
+    count = 0
+    while count < 20 && state == GRPC::Core::ConnectivityStates::READY
+      ch.watch_connectivity_state(state, Time.now + 60)
+      state = ch.connectivity_state
+      count += 1
+    end
+
+    expect(state).to_not be(GRPC::Core::ConnectivityStates::READY)
+
+    start_server(port)
+
+    state = ch.connectivity_state(true)
+
+    count = 0
+    while count < 20 && state != GRPC::Core::ConnectivityStates::READY
+      ch.watch_connectivity_state(state, Time.now + 60)
+      state = ch.connectivity_state(true)
+      count += 1
+    end
+
+    expect(state).to be(GRPC::Core::ConnectivityStates::READY)
+
+    stop_server
+  end
+end
diff --git a/src/ruby/spec/channel_spec.rb b/src/ruby/spec/channel_spec.rb
index 740eac631a..a289a00f04 100644
--- a/src/ruby/spec/channel_spec.rb
+++ b/src/ruby/spec/channel_spec.rb
@@ -153,6 +153,35 @@ describe GRPC::Core::Channel do
     end
   end
 
+  describe '#connectivity_state' do
+    it 'returns an enum' do
+      ch = GRPC::Core::Channel.new(fake_host, nil, :this_channel_is_insecure)
+      valid_states = [
+        GRPC::Core::ConnectivityStates::IDLE,
+        GRPC::Core::ConnectivityStates::CONNECTING,
+        GRPC::Core::ConnectivityStates::READY,
+        GRPC::Core::ConnectivityStates::TRANSIENT_FAILURE,
+        GRPC::Core::ConnectivityStates::FATAL_FAILURE
+      ]
+
+      expect(valid_states).to include(ch.connectivity_state)
+    end
+
+    it 'returns an enum when trying to connect' do
+      ch = GRPC::Core::Channel.new(fake_host, nil, :this_channel_is_insecure)
+      ch.connectivity_state(true)
+      valid_states = [
+        GRPC::Core::ConnectivityStates::IDLE,
+        GRPC::Core::ConnectivityStates::CONNECTING,
+        GRPC::Core::ConnectivityStates::READY,
+        GRPC::Core::ConnectivityStates::TRANSIENT_FAILURE,
+        GRPC::Core::ConnectivityStates::FATAL_FAILURE
+      ]
+
+      expect(valid_states).to include(ch.connectivity_state)
+    end
+  end
+
   describe '::SSL_TARGET' do
     it 'is a symbol' do
       expect(GRPC::Core::Channel::SSL_TARGET).to be_a(Symbol)