sync up with master

15 files changed, 263 insertions, 274 deletions

diff --git a/src/ruby/README.md b/src/ruby/README.md
index 7f7558dc67..7ece7e2706 100755
--- a/src/ruby/README.md
+++ b/src/ruby/README.md
@@ -14,9 +14,10 @@ INSTALLING
 ----------
 
 - Install the gRPC core library
-TODO: describe this, once the core distribution mechanism is defined.
-
+  TODO: describe this, once the core distribution mechanism is defined.
+```
 $ gem install grpc
+```
 
 
 Installing from source
@@ -24,37 +25,47 @@ Installing from source
 
 - Build or Install the gRPC core
 E.g, from the root of the grpc [git repo](https://github.com/google/grpc)
+```
 $ cd ../..
 $ make && sudo make install
+```
 
 - Install Ruby 2.x. Consider doing this with [RVM](http://rvm.io), it's a nice way of controlling
   the exact ruby version that's used.
+```
 $ command curl -sSL https://rvm.io/mpapis.asc | gpg --import -
 $ \curl -sSL https://get.rvm.io | bash -s stable --ruby
 $
 $ # follow the instructions to ensure that your're using the latest stable version of Ruby
 $ # and that the rvm command is installed
+```
 
 - Install [bundler](http://bundler.io/)
+```
 $ gem install bundler
+```
 
 - Finally, install grpc ruby locally.
+```
 $ cd <install_dir>
 $ bundle install
 $ rake  # compiles the extension, runs the unit tests, see rake -T for other options
-
+```
 
 CONTENTS
 --------
 
 Directory structure is the layout for [ruby extensions](http://guides.rubygems.org/gems-with-extensions/)
 
- * ext: the extension code
- * lib: the entrypoint grpc ruby library to be used in a 'require' statement
- * spec: tests
- * bin: example gRPC clients and servers, e.g,
+- ext:
+  the gRPC ruby extension
+- lib:
+  the entrypoint grpc ruby library to be used in a 'require' statement
+- spec:
+  Rspec unittest
+- bin:
+  example gRPC clients and servers, e.g,
 ```ruby
-# client
 stub = Math::Math::Stub.new('my.test.math.server.com:8080')
 req = Math::DivArgs.new(dividend: 7, divisor: 3)
 logger.info("div(7/3): req=#{req.inspect}")
diff --git a/src/ruby/bin/interop/interop_client.rb b/src/ruby/bin/interop/interop_client.rb
index 0ea7f376be..86739b7b67 100755
--- a/src/ruby/bin/interop/interop_client.rb
+++ b/src/ruby/bin/interop/interop_client.rb
@@ -54,6 +54,8 @@ require 'test/cpp/interop/test_services'
 require 'test/cpp/interop/messages'
 require 'test/cpp/interop/empty'
 
+require 'signet/ssl_config'
+
 # loads the certificates used to access the test server securely.
 def load_test_certs
   this_dir = File.expand_path(File.dirname(__FILE__))
@@ -62,21 +64,49 @@ def load_test_certs
   files.map { |f| File.open(File.join(data_dir, f)).read }
 end
 
+# loads the certificates used to access the test server securely.
+def load_prod_cert
+  fail 'could not find a production cert' if ENV['SSL_CERT_FILE'].nil?
+  p "loading prod certs from #{ENV['SSL_CERT_FILE']}"
+  File.open(ENV['SSL_CERT_FILE']).read
+end
+
 # creates a Credentials from the test certificates.
 def test_creds
   certs = load_test_certs
   GRPC::Core::Credentials.new(certs[0])
 end
 
+RX_CERT = /-----BEGIN CERTIFICATE-----\n.*?-----END CERTIFICATE-----\n/m
+
+
+# creates a Credentials from the production certificates.
+def prod_creds
+  cert_text = load_prod_cert
+  GRPC::Core::Credentials.new(cert_text)
+end
+
 # creates a test stub that accesses host:port securely.
-def create_stub(host, port)
+def create_stub(host, port, is_secure, host_override, use_test_ca)
   address = "#{host}:#{port}"
-  stub_opts = {
-    :creds => test_creds,
-    GRPC::Core::Channel::SSL_TARGET => 'foo.test.google.com'
-  }
-  logger.info("... connecting securely to #{address}")
-  Grpc::Testing::TestService::Stub.new(address, **stub_opts)
+  if is_secure
+    creds = nil
+    if use_test_ca
+      creds = test_creds
+    else
+      creds = prod_creds
+    end
+
+    stub_opts = {
+      :creds => creds,
+      GRPC::Core::Channel::SSL_TARGET => host_override
+    }
+    logger.info("... connecting securely to #{address}")
+    Grpc::Testing::TestService::Stub.new(address, **stub_opts)
+  else
+    logger.info("... connecting insecurely to #{address}")
+    Grpc::Testing::TestService::Stub.new(address)
+  end
 end
 
 # produces a string of null chars (\0) of length l.
@@ -133,20 +163,12 @@ class NamedTests
     @stub = stub
   end
 
-  # TESTING
-  # PASSED
-  # FAIL
-  #   ruby server: fails protobuf-ruby can't pass an empty message
   def empty_unary
     resp = @stub.empty_call(Empty.new)
     assert resp.is_a?(Empty), 'empty_unary: invalid response'
     p 'OK: empty_unary'
   end
 
-  # TESTING
-  # PASSED
-  #   ruby server
-  # FAILED
   def large_unary
     req_size, wanted_response_size = 271_828, 314_159
     payload = Payload.new(type: :COMPRESSABLE, body: nulls(req_size))
@@ -163,10 +185,6 @@ class NamedTests
     p 'OK: large_unary'
   end
 
-  # TESTING:
-  # PASSED
-  #   ruby server
-  # FAILED
   def client_streaming
     msg_sizes = [27_182, 8, 1828, 45_904]
     wanted_aggregate_size = 74_922
@@ -180,10 +198,6 @@ class NamedTests
     p 'OK: client_streaming'
   end
 
-  # TESTING:
-  # PASSED
-  #   ruby server
-  # FAILED
   def server_streaming
     msg_sizes = [31_415, 9, 2653, 58_979]
     response_spec = msg_sizes.map { |s| ResponseParameters.new(size: s) }
@@ -200,10 +214,6 @@ class NamedTests
     p 'OK: server_streaming'
   end
 
-  # TESTING:
-  # PASSED
-  #   ruby server
-  # FAILED
   def ping_pong
     msg_sizes = [[27_182, 31_415], [8, 9], [1828, 2653], [45_904, 58_979]]
     ppp = PingPongPlayer.new(msg_sizes)
@@ -211,12 +221,23 @@ class NamedTests
     resps.each { |r| ppp.queue.push(r) }
     p 'OK: ping_pong'
   end
+
+  def all
+    all_methods = NamedTests.instance_methods(false).map(&:to_s)
+    all_methods.each do |m|
+      next if m == 'all' || m.start_with?('assert')
+      p "TESTCASE: #{m}"
+      method(m).call
+    end
+  end
 end
 
 # validates the the command line options, returning them as a Hash.
 def parse_options
   options = {
+    'secure' => false,
     'server_host' => nil,
+    'server_host_override' => nil,
     'server_port' => nil,
     'test_case' => nil
   }
@@ -225,6 +246,10 @@ def parse_options
     opts.on('--server_host SERVER_HOST', 'server hostname') do |v|
       options['server_host'] = v
     end
+    opts.on('--server_host_override HOST_OVERRIDE',
+            'override host via a HTTP header') do |v|
+      options['server_host_override'] = v
+    end
     opts.on('--server_port SERVER_PORT', 'server port') do |v|
       options['server_port'] = v
     end
@@ -235,19 +260,33 @@ def parse_options
             "  (#{test_case_list})") do |v|
       options['test_case'] = v
     end
+    opts.on('-s', '--use_tls', 'require a secure connection?') do |v|
+      options['secure'] = v
+    end
+    opts.on('-t', '--use_test_ca',
+            'if secure, use the test certificate?') do |v|
+      options['use_test_ca'] = v
+    end
   end.parse!
+  _check_options(options)
+end
 
+def _check_options(opts)
   %w(server_host server_port test_case).each do |arg|
-    if options[arg].nil?
+    if opts[arg].nil?
       fail(OptionParser::MissingArgument, "please specify --#{arg}")
     end
   end
-  options
+  if opts['server_host_override'].nil?
+    opts['server_host_override'] = opts['server_host']
+  end
+  opts
 end
 
 def main
   opts = parse_options
-  stub = create_stub(opts['server_host'], opts['server_port'])
+  stub = create_stub(opts['server_host'], opts['server_port'], opts['secure'],
+                     opts['server_host_override'], opts['use_test_ca'])
   NamedTests.new(stub).method(opts['test_case']).call
 end
 
diff --git a/src/ruby/bin/interop/interop_server.rb b/src/ruby/bin/interop/interop_server.rb
index 83212823f6..cc4d260879 100755
--- a/src/ruby/bin/interop/interop_server.rb
+++ b/src/ruby/bin/interop/interop_server.rb
@@ -154,13 +154,17 @@ end
 # validates the the command line options, returning them as a Hash.
 def parse_options
   options = {
-    'port' => nil
+    'port' => nil,
+    'secure' => false
   }
   OptionParser.new do |opts|
     opts.banner = 'Usage: --port port'
     opts.on('--port PORT', 'server port') do |v|
       options['port'] = v
     end
+    opts.on('-s', '--use_tls', 'require a secure connection?') do |v|
+      options['secure'] = v
+    end
   end.parse!
 
   if options['port'].nil?
@@ -172,10 +176,15 @@ end
 def main
   opts = parse_options
   host = "0.0.0.0:#{opts['port']}"
-  s = GRPC::RpcServer.new(creds: test_server_creds)
-  s.add_http2_port(host, true)
-  logger.info("... running securely on #{host}")
-
+  if opts['secure']
+    s = GRPC::RpcServer.new(creds: test_server_creds)
+    s.add_http2_port(host, true)
+    logger.info("... running securely on #{host}")
+  else
+    s = GRPC::RpcServer.new
+    s.add_http2_port(host)
+    logger.info("... running insecurely on #{host}")
+  end
   s.handle(TestTarget)
   s.run
 end
diff --git a/src/ruby/ext/grpc/rb_credentials.c b/src/ruby/ext/grpc/rb_credentials.c
index 50426dece8..87a5d0a299 100644
--- a/src/ruby/ext/grpc/rb_credentials.c
+++ b/src/ruby/ext/grpc/rb_credentials.c
@@ -84,7 +84,6 @@ static void grpc_rb_credentials_mark(void *p) {
 }
 
 /* Allocates Credential instances.
-
    Provides safe initial defaults for the instance fields. */
 static VALUE grpc_rb_credentials_alloc(VALUE cls) {
   grpc_rb_credentials *wrapper = ALLOC(grpc_rb_credentials);
@@ -95,7 +94,6 @@ static VALUE grpc_rb_credentials_alloc(VALUE cls) {
 }
 
 /* Clones Credentials instances.
-
    Gives Credentials a consistent implementation of Ruby's object copy/dup
    protocol. */
 static VALUE grpc_rb_credentials_init_copy(VALUE copy, VALUE orig) {
@@ -124,7 +122,6 @@ static VALUE grpc_rb_credentials_init_copy(VALUE copy, VALUE orig) {
 /*
   call-seq:
     creds = Credentials.default()
-
     Creates the default credential instances. */
 static VALUE grpc_rb_default_credentials_create(VALUE cls) {
   grpc_rb_credentials *wrapper = ALLOC(grpc_rb_credentials);
@@ -143,7 +140,6 @@ static VALUE grpc_rb_default_credentials_create(VALUE cls) {
 /*
   call-seq:
     creds = Credentials.compute_engine()
-
     Creates the default credential instances. */
 static VALUE grpc_rb_compute_engine_credentials_create(VALUE cls) {
   grpc_rb_credentials *wrapper = ALLOC(grpc_rb_credentials);
@@ -164,7 +160,6 @@ static VALUE grpc_rb_compute_engine_credentials_create(VALUE cls) {
     creds1 = ...
     creds2 = ...
     creds3 = creds1.add(creds2)
-
     Creates the default credential instances. */
 static VALUE grpc_rb_composite_credentials_create(VALUE self, VALUE other) {
   grpc_rb_credentials *self_wrapper = NULL;
@@ -202,11 +197,9 @@ static ID id_pem_cert_chain;
     ...
     creds2 = Credentials.new(pem_root_certs, pem_private_key,
                              pem_cert_chain)
-
     pem_root_certs: (required) PEM encoding of the server root certificate
     pem_private_key: (optional) PEM encoding of the client's private key
     pem_cert_chain: (optional) PEM encoding of the client's cert chain
-
     Initializes Credential instances. */
 static VALUE grpc_rb_credentials_init(int argc, VALUE *argv, VALUE self) {
   VALUE pem_root_certs = Qnil;
@@ -214,6 +207,8 @@ static VALUE grpc_rb_credentials_init(int argc, VALUE *argv, VALUE self) {
   VALUE pem_cert_chain = Qnil;
   grpc_rb_credentials *wrapper = NULL;
   grpc_credentials *creds = NULL;
+  grpc_ssl_pem_key_cert_pair key_cert_pair;
+  MEMZERO(&key_cert_pair, grpc_ssl_pem_key_cert_pair, 1);
   /* TODO: Remove mandatory arg when we support default roots. */
   /* "12" == 1 mandatory arg, 2 (credentials) is optional */
   rb_scan_args(argc, argv, "12", &pem_root_certs, &pem_private_key,
@@ -228,10 +223,10 @@ static VALUE grpc_rb_credentials_init(int argc, VALUE *argv, VALUE self) {
   if (pem_private_key == Qnil && pem_cert_chain == Qnil) {
     creds = grpc_ssl_credentials_create(RSTRING_PTR(pem_root_certs), NULL);
   } else {
-    grpc_ssl_pem_key_cert_pair key_cert_pair = {RSTRING_PTR(pem_private_key),
-                                                RSTRING_PTR(pem_cert_chain)};
-    creds = grpc_ssl_credentials_create(RSTRING_PTR(pem_root_certs),
-                                        &key_cert_pair);
+    key_cert_pair.private_key = RSTRING_PTR(pem_private_key);
+    key_cert_pair.cert_chain = RSTRING_PTR(pem_cert_chain);
+    creds = grpc_ssl_credentials_create(
+        RSTRING_PTR(pem_root_certs), &key_cert_pair);
   }
   if (creds == NULL) {
     rb_raise(rb_eRuntimeError, "could not create a credentials, not sure why");
diff --git a/src/ruby/ext/grpc/rb_server.c b/src/ruby/ext/grpc/rb_server.c
index ef2a9f107b..436d006760 100644
--- a/src/ruby/ext/grpc/rb_server.c
+++ b/src/ruby/ext/grpc/rb_server.c
@@ -223,7 +223,7 @@ static VALUE grpc_rb_server_add_http2_port(int argc, VALUE *argv, VALUE self) {
   VALUE port = Qnil;
   VALUE is_secure = Qnil;
   grpc_rb_server *s = NULL;
-  int added_ok = 0;
+  int recvd_port = 0;
 
   /* "11" == 1 mandatory args, 1 (is_secure) is optional */
   rb_scan_args(argc, argv, "11", &port, &is_secure);
@@ -233,22 +233,22 @@ static VALUE grpc_rb_server_add_http2_port(int argc, VALUE *argv, VALUE self) {
     rb_raise(rb_eRuntimeError, "closed!");
     return Qnil;
   } else if (is_secure == Qnil || TYPE(is_secure) != T_TRUE) {
-    added_ok = grpc_server_add_http2_port(s->wrapped, StringValueCStr(port));
-    if (added_ok == 0) {
+    recvd_port = grpc_server_add_http2_port(s->wrapped, StringValueCStr(port));
+    if (recvd_port == 0) {
       rb_raise(rb_eRuntimeError,
                "could not add port %s to server, not sure why",
                StringValueCStr(port));
     }
   } else if (TYPE(is_secure) != T_FALSE) {
-    added_ok =
+    recvd_port =
         grpc_server_add_secure_http2_port(s->wrapped, StringValueCStr(port));
-    if (added_ok == 0) {
+    if (recvd_port == 0) {
       rb_raise(rb_eRuntimeError,
                "could not add secure port %s to server, not sure why",
                StringValueCStr(port));
     }
   }
-  return Qnil;
+  return INT2NUM(recvd_port);
 }
 
 void Init_google_rpc_server() {
diff --git a/src/ruby/grpc.gemspec b/src/ruby/grpc.gemspec
index 450362f5a8..ffd084dc91 100755
--- a/src/ruby/grpc.gemspec
+++ b/src/ruby/grpc.gemspec
@@ -22,6 +22,7 @@ Gem::Specification.new do |s|
   s.add_dependency 'xray'
   s.add_dependency 'logging', '~> 1.8'
   s.add_dependency 'google-protobuf', '~> 3.0.0alpha.1.1'
+  s.add_dependency 'signet', '~> 0.5.1'
   s.add_dependency 'minitest', '~> 5.4'  # reqd for interop tests
 
   s.add_development_dependency 'bundler', '~> 1.7'
diff --git a/src/ruby/lib/grpc/generic/active_call.rb b/src/ruby/lib/grpc/generic/active_call.rb
index 1cdc168bfe..6c2b6e91c2 100644
--- a/src/ruby/lib/grpc/generic/active_call.rb
+++ b/src/ruby/lib/grpc/generic/active_call.rb
@@ -67,7 +67,7 @@ module Google
           fail(ArgumentError, 'not a CompletionQueue')
         end
         call.add_metadata(kw) if kw.length > 0
-        invoke_accepted, client_metadata_read = Object.new, Object.new
+        client_metadata_read = Object.new
         finished_tag = Object.new
         call.invoke(q, client_metadata_read, finished_tag)
         [finished_tag, client_metadata_read]
diff --git a/src/ruby/spec/call_spec.rb b/src/ruby/spec/call_spec.rb
index 9a510df1f3..c793284488 100644
--- a/src/ruby/spec/call_spec.rb
+++ b/src/ruby/spec/call_spec.rb
@@ -28,7 +28,6 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 require 'grpc'
-require 'port_picker'
 
 include GRPC::Core::StatusCodes
 
@@ -71,16 +70,8 @@ describe GRPC::Core::Call do
   before(:each) do
     @tag = Object.new
     @client_queue = GRPC::Core::CompletionQueue.new
-    @server_queue = GRPC::Core::CompletionQueue.new
-    port = find_unused_tcp_port
-    host = "localhost:#{port}"
-    @server = GRPC::Core::Server.new(@server_queue, nil)
-    @server.add_http2_port(host)
-    @ch = GRPC::Core::Channel.new(host, nil)
-  end
-
-  after(:each) do
-    @server.close
+    fake_host = 'localhost:10101'
+    @ch = GRPC::Core::Channel.new(fake_host, nil)
   end
 
   describe '#start_read' do
@@ -122,19 +113,6 @@ describe GRPC::Core::Call do
     end
   end
 
-  describe '#start_write' do
-    it 'should cause the WRITE_ACCEPTED event' do
-      call = make_test_call
-      call.invoke(@client_queue, @tag, @tag)
-      expect(call.start_write(GRPC::Core::ByteBuffer.new('test_start_write'),
-                              @tag)).to be_nil
-      ev = @client_queue.next(deadline)
-      expect(ev.call).to be_a(GRPC::Core::Call)
-      expect(ev.type).to be(GRPC::Core::CompletionType::WRITE_ACCEPTED)
-      expect(ev.tag).to be(@tag)
-    end
-  end
-
   describe '#status' do
     it 'can save the status and read it back' do
       call = make_test_call
diff --git a/src/ruby/spec/channel_spec.rb b/src/ruby/spec/channel_spec.rb
index 820dbd39e9..189d1c67ab 100644
--- a/src/ruby/spec/channel_spec.rb
+++ b/src/ruby/spec/channel_spec.rb
@@ -28,7 +28,8 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 require 'grpc'
-require 'port_picker'
+
+FAKE_HOST='localhost:0'
 
 def load_test_certs
   test_root = File.join(File.dirname(__FILE__), 'testdata')
@@ -114,8 +115,7 @@ describe GRPC::Core::Channel do
 
   describe '#create_call' do
     it 'creates a call OK' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
 
       deadline = Time.now + 5
@@ -127,8 +127,7 @@ describe GRPC::Core::Channel do
     end
 
     it 'raises an error if called on a closed channel' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
       ch.close
 
@@ -142,16 +141,14 @@ describe GRPC::Core::Channel do
 
   describe '#destroy' do
     it 'destroys a channel ok' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
       blk = proc { ch.destroy }
       expect(&blk).to_not raise_error
     end
 
     it 'can be called more than once without error' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
       blk = proc { ch.destroy }
       blk.call
@@ -167,16 +164,14 @@ describe GRPC::Core::Channel do
 
   describe '#close' do
     it 'closes a channel ok' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
       blk = proc { ch.close }
       expect(&blk).to_not raise_error
     end
 
     it 'can be called more than once without error' do
-      port = find_unused_tcp_port
-      host = "localhost:#{port}"
+      host = FAKE_HOST
       ch = GRPC::Core::Channel.new(host, nil)
       blk = proc { ch.close }
       blk.call
diff --git a/src/ruby/spec/client_server_spec.rb b/src/ruby/spec/client_server_spec.rb
index b2afb0581e..96b8ef4300 100644
--- a/src/ruby/spec/client_server_spec.rb
+++ b/src/ruby/spec/client_server_spec.rb
@@ -28,7 +28,6 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 require 'grpc'
-require 'port_picker'
 require 'spec_helper'
 
 include GRPC::Core::CompletionType
@@ -44,12 +43,13 @@ shared_context 'setup: tags' do
   before(:example) do
     @server_finished_tag = Object.new
     @client_finished_tag = Object.new
+    @client_metadata_tag = Object.new
     @server_tag = Object.new
     @tag = Object.new
   end
 
   def deadline
-    Time.now + 0.05
+    Time.now + 2
   end
 
   def expect_next_event_on(queue, type, tag)
@@ -63,27 +63,30 @@ shared_context 'setup: tags' do
     ev
   end
 
-  def server_receives_and_responds_with(reply_text)
-    reply = ByteBuffer.new(reply_text)
+  def server_allows_client_to_proceed
     @server.request_call(@server_tag)
-    ev = @server_queue.pluck(@server_tag, TimeConsts::INFINITE_FUTURE)
+    ev = @server_queue.pluck(@server_tag, deadline)
     expect(ev).not_to be_nil
     expect(ev.type).to be(SERVER_RPC_NEW)
-    ev.call.server_accept(@server_queue, @server_finished_tag)
-    ev.call.server_end_initial_metadata
-    ev.call.start_read(@server_tag)
+    server_call = ev.call
+    server_call.server_accept(@server_queue, @server_finished_tag)
+    server_call.server_end_initial_metadata
+    server_call
+  end
+
+  def server_responds_with(server_call, reply_text)
+    reply = ByteBuffer.new(reply_text)
+    server_call.start_read(@server_tag)
     ev = @server_queue.pluck(@server_tag, TimeConsts::INFINITE_FUTURE)
     expect(ev.type).to be(READ)
-    ev.call.start_write(reply, @server_tag)
+    server_call.start_write(reply, @server_tag)
     ev = @server_queue.pluck(@server_tag, TimeConsts::INFINITE_FUTURE)
     expect(ev).not_to be_nil
     expect(ev.type).to be(WRITE_ACCEPTED)
-    ev.call
   end
 
   def client_sends(call, sent = 'a message')
     req = ByteBuffer.new(sent)
-    call.invoke(@client_queue,  @tag, @client_finished_tag)
     call.start_write(req, @tag)
     ev = @client_queue.pluck(@tag, TimeConsts::INFINITE_FUTURE)
     expect(ev).not_to be_nil
@@ -102,16 +105,20 @@ shared_examples 'basic GRPC message delivery is OK' do
   it 'servers receive requests from clients and start responding' do
     reply = ByteBuffer.new('the server payload')
     call = new_client_call
-    msg = client_sends(call)
+    call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
     # check the server rpc new was received
-    @server.request_call(@server_tag)
-    ev = expect_next_event_on(@server_queue, SERVER_RPC_NEW, @server_tag)
+    # @server.request_call(@server_tag)
+    # ev = expect_next_event_on(@server_queue, SERVER_RPC_NEW, @server_tag)
 
     # accept the call
-    server_call = ev.call
-    server_call.server_accept(@server_queue, @server_finished_tag)
-    server_call.server_end_initial_metadata
+    # server_call = ev.call
+    # server_call.server_accept(@server_queue, @server_finished_tag)
+    # server_call.server_end_initial_metadata
+    server_call = server_allows_client_to_proceed
+
+    # client sends a message
+    msg = client_sends(call)
 
     # confirm the server can read the inbound message
     server_call.start_read(@server_tag)
@@ -125,18 +132,19 @@ shared_examples 'basic GRPC message delivery is OK' do
 
   it 'responses written by servers are received by the client' do
     call = new_client_call
+    call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
+    server_call = server_allows_client_to_proceed
     client_sends(call)
-    server_receives_and_responds_with('server_response')
+    server_responds_with(server_call, 'server_response')
 
     call.start_read(@tag)
-    expect_next_event_on(@client_queue, CLIENT_METADATA_READ, @tag)
     ev = expect_next_event_on(@client_queue, READ, @tag)
     expect(ev.result.to_s).to eq('server_response')
   end
 
   it 'servers can ignore a client write and send a status' do
     call = new_client_call
-    client_sends(call)
+    call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
     # check the server rpc new was received
     @server.request_call(@server_tag)
@@ -150,9 +158,13 @@ shared_examples 'basic GRPC message delivery is OK' do
     server_call.start_write_status(StatusCodes::NOT_FOUND, 'not found',
                                    @server_tag)
 
+    # Client sends some data
+    client_sends(call)
+
     # client gets an empty response for the read, preceeded by some metadata.
     call.start_read(@tag)
-    expect_next_event_on(@client_queue, CLIENT_METADATA_READ, @tag)
+    expect_next_event_on(@client_queue, CLIENT_METADATA_READ,
+                         @client_metadata_tag)
     ev = expect_next_event_on(@client_queue, READ, @tag)
     expect(ev.tag).to be(@tag)
     expect(ev.result.to_s).to eq('')
@@ -166,13 +178,14 @@ shared_examples 'basic GRPC message delivery is OK' do
 
   it 'completes calls by sending status to client and server' do
     call = new_client_call
+    call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
+    server_call = server_allows_client_to_proceed
     client_sends(call)
-    server_call = server_receives_and_responds_with('server_response')
+    server_responds_with(server_call, 'server_response')
     server_call.start_write_status(10_101, 'status code is 10101', @server_tag)
 
     # first the client says writes are done
     call.start_read(@tag)
-    expect_next_event_on(@client_queue, CLIENT_METADATA_READ, @tag)
     expect_next_event_on(@client_queue, READ, @tag)
     call.writes_done(@tag)
 
@@ -215,22 +228,13 @@ shared_examples 'GRPC metadata delivery works OK' do
       end
     end
 
-    it 'sends an empty hash when no metadata is added' do
-      call = new_client_call
-      client_sends(call)
-
-      # Server gets a response
-      @server.request_call(@server_tag)
-      expect_next_event_on(@server_queue, SERVER_RPC_NEW, @server_tag)
-    end
-
     it 'sends all the metadata pairs when keys and values are valid' do
       @valid_metadata.each do |md|
         call = new_client_call
         call.add_metadata(md)
 
         # Client begins a call OK
-        call.invoke(@client_queue, @tag, @client_finished_tag)
+        call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
         # ... server has all metadata available even though the client did not
         # send a write
@@ -262,7 +266,7 @@ shared_examples 'GRPC metadata delivery works OK' do
     it 'raises an exception if a metadata key is invalid' do
       @bad_keys.each do |md|
         call = new_client_call
-        client_sends(call)
+        call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
         # server gets the invocation
         @server.request_call(@server_tag)
@@ -273,7 +277,7 @@ shared_examples 'GRPC metadata delivery works OK' do
 
     it 'sends a hash that contains the status when no metadata is added' do
       call = new_client_call
-      client_sends(call)
+      call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
       # server gets the invocation
       @server.request_call(@server_tag)
@@ -284,21 +288,17 @@ shared_examples 'GRPC metadata delivery works OK' do
       server_call.server_accept(@server_queue, @server_finished_tag)
       server_call.server_end_initial_metadata
 
-      # ... these server sends some data, allowing the metadata read
-      server_call.start_write(ByteBuffer.new('reply with metadata'),
-                              @server_tag)
-      expect_next_event_on(@server_queue, WRITE_ACCEPTED, @server_tag)
-
       # there is the HTTP status metadata, though there should not be any
       # TODO: update this with the bug number to be resolved
-      ev = expect_next_event_on(@client_queue, CLIENT_METADATA_READ, @tag)
+      ev = expect_next_event_on(@client_queue, CLIENT_METADATA_READ,
+                                @client_metadata_tag)
       expect(ev.result).to eq(':status' => '200')
     end
 
     it 'sends all the pairs and status:200 when keys and values are valid' do
       @valid_metadata.each do |md|
         call = new_client_call
-        client_sends(call)
+        call.invoke(@client_queue, @client_metadata_tag, @client_finished_tag)
 
         # server gets the invocation
         @server.request_call(@server_tag)
@@ -311,7 +311,8 @@ shared_examples 'GRPC metadata delivery works OK' do
         server_call.server_end_initial_metadata
 
         # Now the client can read the metadata
-        ev = expect_next_event_on(@client_queue, CLIENT_METADATA_READ, @tag)
+        ev = expect_next_event_on(@client_queue, CLIENT_METADATA_READ,
+                                  @client_metadata_tag)
         replace_symbols = Hash[md.each_pair.collect { |x, y| [x.to_s, y] }]
         replace_symbols[':status'] = '200'
         expect(ev.result).to eq(replace_symbols)
@@ -322,17 +323,17 @@ end
 
 describe 'the http client/server' do
   before(:example) do
-    port = find_unused_tcp_port
-    host = "localhost:#{port}"
+    server_host = '0.0.0.0:0'
     @client_queue = GRPC::Core::CompletionQueue.new
     @server_queue = GRPC::Core::CompletionQueue.new
     @server = GRPC::Core::Server.new(@server_queue, nil)
-    @server.add_http2_port(host)
+    server_port = @server.add_http2_port(server_host)
     @server.start
-    @ch = Channel.new(host, nil)
+    @ch = Channel.new("0.0.0.0:#{server_port}", nil)
   end
 
   after(:example) do
+    @ch.close
     @server.close
   end
 
@@ -346,16 +347,15 @@ end
 describe 'the secure http client/server' do
   before(:example) do
     certs = load_test_certs
-    port = find_unused_tcp_port
-    host = "localhost:#{port}"
+    server_host = 'localhost:0'
     @client_queue = GRPC::Core::CompletionQueue.new
     @server_queue = GRPC::Core::CompletionQueue.new
     server_creds = GRPC::Core::ServerCredentials.new(nil, certs[1], certs[2])
     @server = GRPC::Core::Server.new(@server_queue, nil, server_creds)
-    @server.add_http2_port(host, true)
+    server_port = @server.add_http2_port(server_host, true)
     @server.start
     args = { Channel::SSL_TARGET => 'foo.test.google.com' }
-    @ch = Channel.new(host, args,
+    @ch = Channel.new("0.0.0.0:#{server_port}", args,
                       GRPC::Core::Credentials.new(certs[0], nil, nil))
   end
 
diff --git a/src/ruby/spec/generic/active_call_spec.rb b/src/ruby/spec/generic/active_call_spec.rb
index 443ba3d192..e81b2168b0 100644
--- a/src/ruby/spec/generic/active_call_spec.rb
+++ b/src/ruby/spec/generic/active_call_spec.rb
@@ -28,7 +28,6 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 require 'grpc'
-require_relative '../port_picker'
 
 include GRPC::Core::StatusCodes
 
@@ -45,12 +44,11 @@ describe GRPC::ActiveCall do
 
     @client_queue = GRPC::Core::CompletionQueue.new
     @server_queue = GRPC::Core::CompletionQueue.new
-    port = find_unused_tcp_port
-    host = "localhost:#{port}"
+    host = '0.0.0.0:0'
     @server = GRPC::Core::Server.new(@server_queue, nil)
-    @server.add_http2_port(host)
+    server_port = @server.add_http2_port(host)
     @server.start
-    @ch = GRPC::Core::Channel.new(host, nil)
+    @ch = GRPC::Core::Channel.new("localhost:#{server_port}", nil)
   end
 
   after(:each) do
@@ -206,7 +204,7 @@ describe GRPC::ActiveCall do
     it 'get a nil msg before a status when an OK status is sent' do
       call = make_test_call
       done_tag, meta_tag = ActiveCall.client_invoke(call, @client_queue,
-                                                          deadline)
+                                                    deadline)
       client_call = ActiveCall.new(call, @client_queue, @pass_through,
                                    @pass_through, deadline,
                                    finished_tag: done_tag,
diff --git a/src/ruby/spec/generic/client_stub_spec.rb b/src/ruby/spec/generic/client_stub_spec.rb
index 8ebe48bc4c..f1500fbd44 100644
--- a/src/ruby/spec/generic/client_stub_spec.rb
+++ b/src/ruby/spec/generic/client_stub_spec.rb
@@ -29,9 +29,9 @@
 
 require 'grpc'
 require 'xray/thread_dump_signal_handler'
-require_relative '../port_picker'
 
 NOOP = proc { |x| x }
+FAKE_HOST = 'localhost:0'
 
 def wakey_thread(&blk)
   awake_mutex, awake_cond = Mutex.new, ConditionVariable.new
@@ -67,7 +67,7 @@ describe 'ClientStub' do
 
   describe '#new' do
     it 'can be created from a host and args' do
-      host = new_test_host
+      host = FAKE_HOST
       opts = { a_channel_arg: 'an_arg' }
       blk = proc do
         GRPC::ClientStub.new(host, @cq, **opts)
@@ -76,7 +76,7 @@ describe 'ClientStub' do
     end
 
     it 'can be created with a default deadline' do
-      host = new_test_host
+      host = FAKE_HOST
       opts = { a_channel_arg: 'an_arg', deadline: 5 }
       blk = proc do
         GRPC::ClientStub.new(host, @cq, **opts)
@@ -85,7 +85,7 @@ describe 'ClientStub' do
     end
 
     it 'can be created with an channel override' do
-      host = new_test_host
+      host = FAKE_HOST
       opts = { a_channel_arg: 'an_arg', channel_override: @ch }
       blk = proc do
         GRPC::ClientStub.new(host, @cq, **opts)
@@ -94,7 +94,7 @@ describe 'ClientStub' do
     end
 
     it 'cannot be created with a bad channel override' do
-      host = new_test_host
+      host = FAKE_HOST
       blk = proc do
         opts = { a_channel_arg: 'an_arg', channel_override: Object.new }
         GRPC::ClientStub.new(host, @cq, **opts)
@@ -103,7 +103,7 @@ describe 'ClientStub' do
     end
 
     it 'cannot be created with bad credentials' do
-      host = new_test_host
+      host = FAKE_HOST
       blk = proc do
         opts = { a_channel_arg: 'an_arg', creds: Object.new }
         GRPC::ClientStub.new(host, @cq, **opts)
@@ -113,7 +113,7 @@ describe 'ClientStub' do
 
     it 'can be created with test test credentials' do
       certs = load_test_certs
-      host = new_test_host
+      host = FAKE_HOST
       blk = proc do
         opts = {
           GRPC::Core::Channel::SSL_TARGET => 'foo.test.google.com',
@@ -133,16 +133,17 @@ describe 'ClientStub' do
 
     shared_examples 'request response' do
       it 'should send a request to/receive a reply from a server' do
-        host = new_test_host
-        th = run_request_response(host, @sent_msg, @resp, @pass)
-        stub = GRPC::ClientStub.new(host, @cq)
+        server_port = create_test_server
+        th = run_request_response(@sent_msg, @resp, @pass)
+        stub = GRPC::ClientStub.new("localhost:#{server_port}", @cq)
         expect(get_response(stub)).to eq(@resp)
         th.join
       end
 
       it 'should send metadata to the server ok' do
-        host = new_test_host
-        th = run_request_response(host, @sent_msg, @resp, @pass,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_request_response(@sent_msg, @resp, @pass,
                                   k1: 'v1', k2: 'v2')
         stub = GRPC::ClientStub.new(host, @cq)
         expect(get_response(stub)).to eq(@resp)
@@ -150,8 +151,9 @@ describe 'ClientStub' do
       end
 
       it 'should update the sent metadata with a provided metadata updater' do
-        host = new_test_host
-        th = run_request_response(host, @sent_msg, @resp, @pass,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_request_response(@sent_msg, @resp, @pass,
                                   k1: 'updated-v1', k2: 'v2')
         update_md = proc do |md|
           md[:k1] = 'updated-v1'
@@ -163,8 +165,9 @@ describe 'ClientStub' do
       end
 
       it 'should send a request when configured using an override channel' do
-        alt_host = new_test_host
-        th = run_request_response(alt_host, @sent_msg, @resp, @pass)
+        server_port = create_test_server
+        alt_host = "localhost:#{server_port}"
+        th = run_request_response(@sent_msg, @resp, @pass)
         ch = GRPC::Core::Channel.new(alt_host, nil)
         stub = GRPC::ClientStub.new('ignored-host', @cq, channel_override: ch)
         expect(get_response(stub)).to eq(@resp)
@@ -172,8 +175,9 @@ describe 'ClientStub' do
       end
 
       it 'should raise an error if the status is not OK' do
-        host = new_test_host
-        th = run_request_response(host, @sent_msg, @resp, @fail)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_request_response(@sent_msg, @resp, @fail)
         stub = GRPC::ClientStub.new(host, @cq)
         blk = proc { get_response(stub) }
         expect(&blk).to raise_error(GRPC::BadStatus)
@@ -210,16 +214,18 @@ describe 'ClientStub' do
       end
 
       it 'should send requests to/receive a reply from a server' do
-        host = new_test_host
-        th = run_client_streamer(host, @sent_msgs, @resp, @pass)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_client_streamer(@sent_msgs, @resp, @pass)
         stub = GRPC::ClientStub.new(host, @cq)
         expect(get_response(stub)).to eq(@resp)
         th.join
       end
 
       it 'should send metadata to the server ok' do
-        host = new_test_host
-        th = run_client_streamer(host, @sent_msgs, @resp, @pass,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_client_streamer(@sent_msgs, @resp, @pass,
                                  k1: 'v1', k2: 'v2')
         stub = GRPC::ClientStub.new(host, @cq)
         expect(get_response(stub)).to eq(@resp)
@@ -227,8 +233,9 @@ describe 'ClientStub' do
       end
 
       it 'should update the sent metadata with a provided metadata updater' do
-        host = new_test_host
-        th = run_client_streamer(host, @sent_msgs, @resp, @pass,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_client_streamer(@sent_msgs, @resp, @pass,
                                  k1: 'updated-v1', k2: 'v2')
         update_md = proc do |md|
           md[:k1] = 'updated-v1'
@@ -240,8 +247,9 @@ describe 'ClientStub' do
       end
 
       it 'should raise an error if the status is not ok' do
-        host = new_test_host
-        th = run_client_streamer(host, @sent_msgs, @resp, @fail)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_client_streamer(@sent_msgs, @resp, @fail)
         stub = GRPC::ClientStub.new(host, @cq)
         blk = proc { get_response(stub) }
         expect(&blk).to raise_error(GRPC::BadStatus)
@@ -278,16 +286,18 @@ describe 'ClientStub' do
       end
 
       it 'should send a request to/receive replies from a server' do
-        host = new_test_host
-        th = run_server_streamer(host, @sent_msg, @replys, @pass)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_server_streamer(@sent_msg, @replys, @pass)
         stub = GRPC::ClientStub.new(host, @cq)
         expect(get_responses(stub).collect { |r| r }).to eq(@replys)
         th.join
       end
 
       it 'should raise an error if the status is not ok' do
-        host = new_test_host
-        th = run_server_streamer(host, @sent_msg, @replys, @fail)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_server_streamer(@sent_msg, @replys, @fail)
         stub = GRPC::ClientStub.new(host, @cq)
         e = get_responses(stub)
         expect { e.collect { |r| r } }.to raise_error(GRPC::BadStatus)
@@ -295,8 +305,9 @@ describe 'ClientStub' do
       end
 
       it 'should send metadata to the server ok' do
-        host = new_test_host
-        th = run_server_streamer(host, @sent_msg, @replys, @fail,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_server_streamer(@sent_msg, @replys, @fail,
                                  k1: 'v1', k2: 'v2')
         stub = GRPC::ClientStub.new(host, @cq)
         e = get_responses(stub)
@@ -305,8 +316,9 @@ describe 'ClientStub' do
       end
 
       it 'should update the sent metadata with a provided metadata updater' do
-        host = new_test_host
-        th = run_server_streamer(host, @sent_msg, @replys, @pass,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_server_streamer(@sent_msg, @replys, @pass,
                                  k1: 'updated-v1', k2: 'v2')
         update_md = proc do |md|
           md[:k1] = 'updated-v1'
@@ -352,8 +364,9 @@ describe 'ClientStub' do
       end
 
       it 'supports sending all the requests first', bidi: true do
-        host = new_test_host
-        th = run_bidi_streamer_handle_inputs_first(host, @sent_msgs, @replys,
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_bidi_streamer_handle_inputs_first(@sent_msgs, @replys,
                                                    @pass)
         stub = GRPC::ClientStub.new(host, @cq)
         e = get_responses(stub)
@@ -362,8 +375,9 @@ describe 'ClientStub' do
       end
 
       it 'supports client-initiated ping pong', bidi: true do
-        host = new_test_host
-        th = run_bidi_streamer_echo_ping_pong(host, @sent_msgs, @pass, true)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_bidi_streamer_echo_ping_pong(@sent_msgs, @pass, true)
         stub = GRPC::ClientStub.new(host, @cq)
         e = get_responses(stub)
         expect(e.collect { |r| r }).to eq(@sent_msgs)
@@ -377,8 +391,9 @@ describe 'ClientStub' do
       # they receive a message from the client.  Without receiving all the
       # metadata, the server does not accept the call, so this test hangs.
       xit 'supports a server-initiated ping pong', bidi: true do
-        host = new_test_host
-        th = run_bidi_streamer_echo_ping_pong(host, @sent_msgs, @pass, false)
+        server_port = create_test_server
+        host = "localhost:#{server_port}"
+        th = run_bidi_streamer_echo_ping_pong(@sent_msgs, @pass, false)
         stub = GRPC::ClientStub.new(host, @cq)
         e = get_responses(stub)
         expect(e.collect { |r| r }).to eq(@sent_msgs)
@@ -410,10 +425,10 @@ describe 'ClientStub' do
     end
   end
 
-  def run_server_streamer(hostname, expected_input, replys, status, **kw)
+  def run_server_streamer(expected_input, replys, status, **kw)
     wanted_metadata = kw.clone
     wakey_thread do |mtx, cnd|
-      c = expect_server_to_be_invoked(hostname, mtx, cnd)
+      c = expect_server_to_be_invoked(mtx, cnd)
       wanted_metadata.each do |k, v|
         expect(c.metadata[k.to_s]).to eq(v)
       end
@@ -423,20 +438,19 @@ describe 'ClientStub' do
     end
   end
 
-  def run_bidi_streamer_handle_inputs_first(hostname, expected_inputs, replys,
+  def run_bidi_streamer_handle_inputs_first(expected_inputs, replys,
                                             status)
     wakey_thread do |mtx, cnd|
-      c = expect_server_to_be_invoked(hostname, mtx, cnd)
+      c = expect_server_to_be_invoked(mtx, cnd)
       expected_inputs.each { |i| expect(c.remote_read).to eq(i) }
       replys.each { |r| c.remote_send(r) }
       c.send_status(status, status == @pass ? 'OK' : 'NOK', true)
     end
   end
 
-  def run_bidi_streamer_echo_ping_pong(hostname, expected_inputs, status,
-                                       client_starts)
+  def run_bidi_streamer_echo_ping_pong(expected_inputs, status, client_starts)
     wakey_thread do |mtx, cnd|
-      c = expect_server_to_be_invoked(hostname, mtx, cnd)
+      c = expect_server_to_be_invoked(mtx, cnd)
       expected_inputs.each do |i|
         if client_starts
           expect(c.remote_read).to eq(i)
@@ -450,10 +464,10 @@ describe 'ClientStub' do
     end
   end
 
-  def run_client_streamer(hostname, expected_inputs, resp, status, **kw)
+  def run_client_streamer(expected_inputs, resp, status, **kw)
     wanted_metadata = kw.clone
     wakey_thread do |mtx, cnd|
-      c = expect_server_to_be_invoked(hostname, mtx, cnd)
+      c = expect_server_to_be_invoked(mtx, cnd)
       expected_inputs.each { |i| expect(c.remote_read).to eq(i) }
       wanted_metadata.each do |k, v|
         expect(c.metadata[k.to_s]).to eq(v)
@@ -463,10 +477,10 @@ describe 'ClientStub' do
     end
   end
 
-  def run_request_response(hostname, expected_input, resp, status, **kw)
+  def run_request_response(expected_input, resp, status, **kw)
     wanted_metadata = kw.clone
     wakey_thread do |mtx, cnd|
-      c = expect_server_to_be_invoked(hostname, mtx, cnd)
+      c = expect_server_to_be_invoked(mtx, cnd)
       expect(c.remote_read).to eq(expected_input)
       wanted_metadata.each do |k, v|
         expect(c.metadata[k.to_s]).to eq(v)
@@ -476,32 +490,30 @@ describe 'ClientStub' do
     end
   end
 
-  def start_test_server(hostname, awake_mutex, awake_cond)
-    server_queue = GRPC::Core::CompletionQueue.new
-    @server = GRPC::Core::Server.new(server_queue, nil)
-    @server.add_http2_port(hostname)
+  def create_test_server
+    @server_queue = GRPC::Core::CompletionQueue.new
+    @server = GRPC::Core::Server.new(@server_queue, nil)
+    @server.add_http2_port('0.0.0.0:0')
+  end
+
+  def start_test_server(awake_mutex, awake_cond)
     @server.start
     @server_tag = Object.new
     @server.request_call(@server_tag)
     awake_mutex.synchronize { awake_cond.signal }
-    server_queue
   end
 
-  def expect_server_to_be_invoked(hostname, awake_mutex, awake_cond)
-    server_queue = start_test_server(hostname, awake_mutex, awake_cond)
-    ev = server_queue.pluck(@server_tag, INFINITE_FUTURE)
+  def expect_server_to_be_invoked(awake_mutex, awake_cond)
+    start_test_server(awake_mutex, awake_cond)
+    ev = @server_queue.pluck(@server_tag, INFINITE_FUTURE)
     fail OutOfTime if ev.nil?
     server_call = ev.call
     server_call.metadata = ev.result.metadata
     finished_tag = Object.new
-    server_call.server_accept(server_queue, finished_tag)
+    server_call.server_accept(@server_queue, finished_tag)
     server_call.server_end_initial_metadata
-    GRPC::ActiveCall.new(server_call, server_queue, NOOP, NOOP, INFINITE_FUTURE,
+    GRPC::ActiveCall.new(server_call, @server_queue, NOOP, NOOP,
+                         INFINITE_FUTURE,
                          finished_tag: finished_tag)
   end
-
-  def new_test_host
-    port = find_unused_tcp_port
-    "localhost:#{port}"
-  end
 end
diff --git a/src/ruby/spec/generic/rpc_server_spec.rb b/src/ruby/spec/generic/rpc_server_spec.rb
index cd4888a3b4..e083bc1e9d 100644
--- a/src/ruby/spec/generic/rpc_server_spec.rb
+++ b/src/ruby/spec/generic/rpc_server_spec.rb
@@ -29,7 +29,6 @@
 
 require 'grpc'
 require 'xray/thread_dump_signal_handler'
-require_relative '../port_picker'
 
 def load_test_certs
   test_root = File.join(File.dirname(File.dirname(__FILE__)), 'testdata')
@@ -104,10 +103,10 @@ describe GRPC::RpcServer do
     @noop = proc { |x| x }
 
     @server_queue = GRPC::Core::CompletionQueue.new
-    port = find_unused_tcp_port
-    @host = "localhost:#{port}"
+    server_host = '0.0.0.0:0'
     @server = GRPC::Core::Server.new(@server_queue, nil)
-    @server.add_http2_port(@host)
+    server_port = @server.add_http2_port(server_host)
+    @host = "localhost:#{server_port}"
     @ch = GRPC::Core::Channel.new(@host, nil)
   end
 
diff --git a/src/ruby/spec/port_picker.rb b/src/ruby/spec/port_picker.rb
deleted file mode 100644
index 98ffbacc1b..0000000000
--- a/src/ruby/spec/port_picker.rb
+++ /dev/null
@@ -1,45 +0,0 @@
-# Copyright 2014, 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 'socket'
-
-# @param [Fixnum] the minimum port number to accept
-# @param [Fixnum] the maximum port number to accept
-# @return [Fixnum ]a free tcp port
-def find_unused_tcp_port(min = 32_768, max = 60_000)
-  # Allow the system to assign a port, by specifying 0.
-  # Loop until a port is assigned in the required range
-  loop do
-    socket = Socket.new(:INET, :STREAM, 0)
-    socket.bind(Addrinfo.tcp('127.0.0.1', 0))
-    p = socket.local_address.ip_port
-    socket.close
-    return p if p > min && p < max
-  end
-end
diff --git a/src/ruby/spec/server_spec.rb b/src/ruby/spec/server_spec.rb
index 6e5bb523de..1550ba6566 100644
--- a/src/ruby/spec/server_spec.rb
+++ b/src/ruby/spec/server_spec.rb
@@ -28,7 +28,6 @@
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 require 'grpc'
-require 'port_picker'
 
 def load_test_certs
   test_root = File.join(File.dirname(__FILE__), 'testdata')
@@ -205,10 +204,8 @@ describe Server do
   end
 
   def start_a_server
-    port = find_unused_tcp_port
-    host = "localhost:#{port}"
     s = Server.new(@cq, nil)
-    s.add_http2_port(host)
+    s.add_http2_port('0.0.0.0:0')
     s.start
     s
   end