TIPS client implementation.

12 files changed, 1641 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 7668ca8b74..db835c8f7a 100644
--- a/Makefile
+++ b/Makefile
@@ -363,6 +363,8 @@ qps_client: bins/$(CONFIG)/qps_client
 qps_server: bins/$(CONFIG)/qps_server
 interop_server: bins/$(CONFIG)/interop_server
 interop_client: bins/$(CONFIG)/interop_client
+tips_client: bins/$(CONFIG)/tips_client
+tips_client_test: bins/$(CONFIG)/tips_client_test
 end2end_test: bins/$(CONFIG)/end2end_test
 channel_arguments_test: bins/$(CONFIG)/channel_arguments_test
 credentials_test: bins/$(CONFIG)/credentials_test
@@ -539,13 +541,13 @@ privatelibs: privatelibs_c privatelibs_cxx
 
 privatelibs_c:  libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libend2end_fixture_chttp2_fake_security.a libs/$(CONFIG)/libend2end_fixture_chttp2_fullstack.a libs/$(CONFIG)/libend2end_fixture_chttp2_simple_ssl_fullstack.a libs/$(CONFIG)/libend2end_fixture_chttp2_simple_ssl_with_oauth2_fullstack.a libs/$(CONFIG)/libend2end_fixture_chttp2_socket_pair.a libs/$(CONFIG)/libend2end_fixture_chttp2_socket_pair_one_byte_at_a_time.a libs/$(CONFIG)/libend2end_test_cancel_after_accept.a libs/$(CONFIG)/libend2end_test_cancel_after_accept_and_writes_closed.a libs/$(CONFIG)/libend2end_test_cancel_after_invoke.a libs/$(CONFIG)/libend2end_test_cancel_before_invoke.a libs/$(CONFIG)/libend2end_test_cancel_in_a_vacuum.a libs/$(CONFIG)/libend2end_test_census_simple_request.a libs/$(CONFIG)/libend2end_test_disappearing_server.a libs/$(CONFIG)/libend2end_test_early_server_shutdown_finishes_inflight_calls.a libs/$(CONFIG)/libend2end_test_early_server_shutdown_finishes_tags.a libs/$(CONFIG)/libend2end_test_graceful_server_shutdown.a libs/$(CONFIG)/libend2end_test_invoke_large_request.a libs/$(CONFIG)/libend2end_test_max_concurrent_streams.a libs/$(CONFIG)/libend2end_test_no_op.a libs/$(CONFIG)/libend2end_test_ping_pong_streaming.a libs/$(CONFIG)/libend2end_test_request_response_with_binary_metadata_and_payload.a libs/$(CONFIG)/libend2end_test_request_response_with_metadata_and_payload.a libs/$(CONFIG)/libend2end_test_request_response_with_payload.a libs/$(CONFIG)/libend2end_test_request_response_with_trailing_metadata_and_payload.a libs/$(CONFIG)/libend2end_test_simple_delayed_request.a libs/$(CONFIG)/libend2end_test_simple_request.a libs/$(CONFIG)/libend2end_test_thread_stress.a libs/$(CONFIG)/libend2end_test_writes_done_hangs_with_pending_read.a libs/$(CONFIG)/libend2end_certs.a
 
-privatelibs_cxx:  libs/$(CONFIG)/libgrpc++_test_util.a
+privatelibs_cxx:  libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libtips_client_lib.a
 
 buildtests: buildtests_c buildtests_cxx
 
 buildtests_c: privatelibs_c bins/$(CONFIG)/grpc_byte_buffer_reader_test bins/$(CONFIG)/gpr_cancellable_test bins/$(CONFIG)/gpr_log_test bins/$(CONFIG)/gpr_useful_test bins/$(CONFIG)/gpr_cmdline_test bins/$(CONFIG)/gpr_histogram_test bins/$(CONFIG)/gpr_host_port_test bins/$(CONFIG)/gpr_slice_buffer_test bins/$(CONFIG)/gpr_slice_test bins/$(CONFIG)/gpr_string_test bins/$(CONFIG)/gpr_sync_test bins/$(CONFIG)/gpr_thd_test bins/$(CONFIG)/gpr_time_test bins/$(CONFIG)/murmur_hash_test bins/$(CONFIG)/grpc_stream_op_test bins/$(CONFIG)/alpn_test bins/$(CONFIG)/time_averaged_stats_test bins/$(CONFIG)/chttp2_stream_encoder_test bins/$(CONFIG)/hpack_table_test bins/$(CONFIG)/chttp2_stream_map_test bins/$(CONFIG)/hpack_parser_test bins/$(CONFIG)/transport_metadata_test bins/$(CONFIG)/chttp2_status_conversion_test bins/$(CONFIG)/chttp2_transport_end2end_test bins/$(CONFIG)/tcp_posix_test bins/$(CONFIG)/dualstack_socket_test bins/$(CONFIG)/no_server_test bins/$(CONFIG)/resolve_address_test bins/$(CONFIG)/sockaddr_utils_test bins/$(CONFIG)/tcp_server_posix_test bins/$(CONFIG)/tcp_client_posix_test bins/$(CONFIG)/grpc_channel_stack_test bins/$(CONFIG)/metadata_buffer_test bins/$(CONFIG)/grpc_completion_queue_test bins/$(CONFIG)/census_window_stats_test bins/$(CONFIG)/census_statistics_quick_test bins/$(CONFIG)/census_statistics_small_log_test bins/$(CONFIG)/census_statistics_performance_test bins/$(CONFIG)/census_statistics_multiple_writers_test bins/$(CONFIG)/census_statistics_multiple_writers_circular_buffer_test bins/$(CONFIG)/census_stub_test bins/$(CONFIG)/census_hash_table_test bins/$(CONFIG)/fling_server bins/$(CONFIG)/fling_client bins/$(CONFIG)/fling_test bins/$(CONFIG)/echo_server bins/$(CONFIG)/echo_client bins/$(CONFIG)/echo_test bins/$(CONFIG)/message_compress_test bins/$(CONFIG)/bin_encoder_test bins/$(CONFIG)/secure_endpoint_test bins/$(CONFIG)/httpcli_format_request_test bins/$(CONFIG)/httpcli_parser_test bins/$(CONFIG)/httpcli_test bins/$(CONFIG)/grpc_credentials_test bins/$(CONFIG)/grpc_base64_test bins/$(CONFIG)/grpc_json_token_test bins/$(CONFIG)/timeout_encoding_test bins/$(CONFIG)/fd_posix_test bins/$(CONFIG)/fling_stream_test bins/$(CONFIG)/lame_client_test bins/$(CONFIG)/alarm_test bins/$(CONFIG)/alarm_list_test bins/$(CONFIG)/alarm_heap_test bins/$(CONFIG)/time_test bins/$(CONFIG)/chttp2_fake_security_cancel_after_accept_test bins/$(CONFIG)/chttp2_fake_security_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_fake_security_cancel_after_invoke_test bins/$(CONFIG)/chttp2_fake_security_cancel_before_invoke_test bins/$(CONFIG)/chttp2_fake_security_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_fake_security_census_simple_request_test bins/$(CONFIG)/chttp2_fake_security_disappearing_server_test bins/$(CONFIG)/chttp2_fake_security_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_fake_security_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_fake_security_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_fake_security_invoke_large_request_test bins/$(CONFIG)/chttp2_fake_security_max_concurrent_streams_test bins/$(CONFIG)/chttp2_fake_security_no_op_test bins/$(CONFIG)/chttp2_fake_security_ping_pong_streaming_test bins/$(CONFIG)/chttp2_fake_security_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_fake_security_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_fake_security_request_response_with_payload_test bins/$(CONFIG)/chttp2_fake_security_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_fake_security_simple_delayed_request_test bins/$(CONFIG)/chttp2_fake_security_simple_request_test bins/$(CONFIG)/chttp2_fake_security_thread_stress_test bins/$(CONFIG)/chttp2_fake_security_writes_done_hangs_with_pending_read_test bins/$(CONFIG)/chttp2_fullstack_cancel_after_accept_test bins/$(CONFIG)/chttp2_fullstack_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_fullstack_cancel_after_invoke_test bins/$(CONFIG)/chttp2_fullstack_cancel_before_invoke_test bins/$(CONFIG)/chttp2_fullstack_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_fullstack_census_simple_request_test bins/$(CONFIG)/chttp2_fullstack_disappearing_server_test bins/$(CONFIG)/chttp2_fullstack_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_fullstack_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_fullstack_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_fullstack_invoke_large_request_test bins/$(CONFIG)/chttp2_fullstack_max_concurrent_streams_test bins/$(CONFIG)/chttp2_fullstack_no_op_test bins/$(CONFIG)/chttp2_fullstack_ping_pong_streaming_test bins/$(CONFIG)/chttp2_fullstack_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_fullstack_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_fullstack_request_response_with_payload_test bins/$(CONFIG)/chttp2_fullstack_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_fullstack_simple_delayed_request_test bins/$(CONFIG)/chttp2_fullstack_simple_request_test bins/$(CONFIG)/chttp2_fullstack_thread_stress_test bins/$(CONFIG)/chttp2_fullstack_writes_done_hangs_with_pending_read_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_cancel_after_accept_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_cancel_after_invoke_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_cancel_before_invoke_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_census_simple_request_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_disappearing_server_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_invoke_large_request_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_max_concurrent_streams_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_no_op_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_ping_pong_streaming_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_request_response_with_payload_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_simple_delayed_request_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_simple_request_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_thread_stress_test bins/$(CONFIG)/chttp2_simple_ssl_fullstack_writes_done_hangs_with_pending_read_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_cancel_after_accept_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_cancel_after_invoke_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_cancel_before_invoke_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_census_simple_request_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_disappearing_server_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_invoke_large_request_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_max_concurrent_streams_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_no_op_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_ping_pong_streaming_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_request_response_with_payload_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_simple_delayed_request_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_simple_request_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_thread_stress_test bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_writes_done_hangs_with_pending_read_test bins/$(CONFIG)/chttp2_socket_pair_cancel_after_accept_test bins/$(CONFIG)/chttp2_socket_pair_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_socket_pair_cancel_after_invoke_test bins/$(CONFIG)/chttp2_socket_pair_cancel_before_invoke_test bins/$(CONFIG)/chttp2_socket_pair_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_socket_pair_census_simple_request_test bins/$(CONFIG)/chttp2_socket_pair_disappearing_server_test bins/$(CONFIG)/chttp2_socket_pair_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_socket_pair_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_socket_pair_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_socket_pair_invoke_large_request_test bins/$(CONFIG)/chttp2_socket_pair_max_concurrent_streams_test bins/$(CONFIG)/chttp2_socket_pair_no_op_test bins/$(CONFIG)/chttp2_socket_pair_ping_pong_streaming_test bins/$(CONFIG)/chttp2_socket_pair_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_request_response_with_payload_test bins/$(CONFIG)/chttp2_socket_pair_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_simple_delayed_request_test bins/$(CONFIG)/chttp2_socket_pair_simple_request_test bins/$(CONFIG)/chttp2_socket_pair_thread_stress_test bins/$(CONFIG)/chttp2_socket_pair_writes_done_hangs_with_pending_read_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_cancel_after_accept_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_cancel_after_accept_and_writes_closed_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_cancel_after_invoke_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_cancel_before_invoke_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_cancel_in_a_vacuum_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_census_simple_request_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_disappearing_server_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_early_server_shutdown_finishes_inflight_calls_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_early_server_shutdown_finishes_tags_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_graceful_server_shutdown_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_invoke_large_request_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_max_concurrent_streams_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_no_op_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_ping_pong_streaming_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_request_response_with_binary_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_request_response_with_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_request_response_with_payload_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_request_response_with_trailing_metadata_and_payload_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_simple_delayed_request_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_simple_request_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_thread_stress_test bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_writes_done_hangs_with_pending_read_test
 
-buildtests_cxx: privatelibs_cxx bins/$(CONFIG)/thread_pool_test bins/$(CONFIG)/status_test bins/$(CONFIG)/sync_client_async_server_test bins/$(CONFIG)/qps_client bins/$(CONFIG)/qps_server bins/$(CONFIG)/interop_server bins/$(CONFIG)/interop_client bins/$(CONFIG)/end2end_test bins/$(CONFIG)/channel_arguments_test bins/$(CONFIG)/credentials_test
+buildtests_cxx: privatelibs_cxx bins/$(CONFIG)/thread_pool_test bins/$(CONFIG)/status_test bins/$(CONFIG)/sync_client_async_server_test bins/$(CONFIG)/qps_client bins/$(CONFIG)/qps_server bins/$(CONFIG)/interop_server bins/$(CONFIG)/interop_client bins/$(CONFIG)/tips_client bins/$(CONFIG)/tips_client_test bins/$(CONFIG)/end2end_test bins/$(CONFIG)/channel_arguments_test bins/$(CONFIG)/credentials_test
 
 test: test_c test_cxx
 
@@ -949,6 +951,8 @@ test_cxx: buildtests_cxx
 	$(Q) ./bins/$(CONFIG)/qps_client || ( echo test qps_client failed ; exit 1 )
 	$(E) "[RUN]     Testing qps_server"
 	$(Q) ./bins/$(CONFIG)/qps_server || ( echo test qps_server failed ; exit 1 )
+	$(E) "[RUN]     Testing tips_client_test"
+	$(Q) ./bins/$(CONFIG)/tips_client_test || ( echo test tips_client_test failed ; exit 1 )
 	$(E) "[RUN]     Testing end2end_test"
 	$(Q) ./bins/$(CONFIG)/end2end_test || ( echo test end2end_test failed ; exit 1 )
 	$(E) "[RUN]     Testing channel_arguments_test"
@@ -998,6 +1002,21 @@ strip-shared_cxx: shared_cxx
 	$(E) "[STRIP]   Stripping libgrpc++.so"
 	$(Q) $(STRIP) libs/$(CONFIG)/libgrpc++.$(SHARED_EXT)
 
+gens/examples/tips/empty.pb.cc: examples/tips/empty.proto $(PROTOC_PLUGINS)
+	$(E) "[PROTOC]  Generating protobuf CC file from $<"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(PROTOC) --cpp_out=gens --grpc_out=gens --plugin=protoc-gen-grpc=bins/$(CONFIG)/cpp_plugin $<
+
+gens/examples/tips/label.pb.cc: examples/tips/label.proto $(PROTOC_PLUGINS)
+	$(E) "[PROTOC]  Generating protobuf CC file from $<"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(PROTOC) --cpp_out=gens --grpc_out=gens --plugin=protoc-gen-grpc=bins/$(CONFIG)/cpp_plugin $<
+
+gens/examples/tips/pubsub.pb.cc: examples/tips/pubsub.proto $(PROTOC_PLUGINS)
+	$(E) "[PROTOC]  Generating protobuf CC file from $<"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(PROTOC) --cpp_out=gens --grpc_out=gens --plugin=protoc-gen-grpc=bins/$(CONFIG)/cpp_plugin $<
+
 gens/test/cpp/interop/empty.pb.cc: test/cpp/interop/empty.proto $(PROTOC_PLUGINS)
 	$(E) "[PROTOC]  Generating protobuf CC file from $<"
 	$(Q) mkdir -p `dirname $@`
@@ -2108,6 +2127,54 @@ objs/$(CONFIG)/test/cpp/util/create_test_channel.o:     gens/test/cpp/util/messa
 objs/$(CONFIG)/test/cpp/end2end/async_test_server.o:     gens/test/cpp/util/messages.pb.cc    gens/test/cpp/util/echo.pb.cc    gens/test/cpp/util/echo_duplicate.pb.cc
 
 
+LIBTIPS_CLIENT_LIB_SRC = \
+    gens/examples/tips/label.pb.cc \
+    gens/examples/tips/empty.pb.cc \
+    gens/examples/tips/pubsub.pb.cc \
+    examples/tips/client.cc \
+
+
+LIBTIPS_CLIENT_LIB_OBJS = $(addprefix objs/$(CONFIG)/, $(addsuffix .o, $(basename $(LIBTIPS_CLIENT_LIB_SRC))))
+
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure libraries if you don't have OpenSSL with ALPN.
+
+libs/$(CONFIG)/libtips_client_lib.a: openssl_dep_error
+
+
+else
+
+ifneq ($(OPENSSL_DEP),)
+examples/tips/label.proto: $(OPENSSL_DEP)
+examples/tips/empty.proto: $(OPENSSL_DEP)
+examples/tips/pubsub.proto: $(OPENSSL_DEP)
+examples/tips/client.cc: $(OPENSSL_DEP)
+endif
+
+libs/$(CONFIG)/libtips_client_lib.a: $(ZLIB_DEP) $(OPENSSL_DEP) $(LIBTIPS_CLIENT_LIB_OBJS)
+	$(E) "[AR]      Creating $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(AR) rcs libs/$(CONFIG)/libtips_client_lib.a $(LIBTIPS_CLIENT_LIB_OBJS)
+
+
+
+
+
+endif
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(LIBTIPS_CLIENT_LIB_OBJS:.o=.dep)
+endif
+endif
+
+
+
+
+objs/$(CONFIG)/examples/tips/client.o:     gens/examples/tips/label.pb.cc    gens/examples/tips/empty.pb.cc    gens/examples/tips/pubsub.pb.cc
+
+
 LIBEND2END_FIXTURE_CHTTP2_FAKE_SECURITY_SRC = \
     test/core/end2end/fixtures/chttp2_fake_security.c \
 
@@ -5230,6 +5297,68 @@ endif
 endif
 
 
+TIPS_CLIENT_SRC = \
+    examples/tips/client_main.cc \
+
+TIPS_CLIENT_OBJS = $(addprefix objs/$(CONFIG)/, $(addsuffix .o, $(basename $(TIPS_CLIENT_SRC))))
+
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
+bins/$(CONFIG)/tips_client: openssl_dep_error
+
+else
+
+bins/$(CONFIG)/tips_client: $(TIPS_CLIENT_OBJS) libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(TIPS_CLIENT_OBJS) $(GTEST_LIB) libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a $(LDLIBSXX) $(LDLIBS) $(LDLIBS_SECURE) -o bins/$(CONFIG)/tips_client
+
+endif
+
+objs/$(CONFIG)/examples/tips/client_main.o:  libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a
+
+deps_tips_client: $(TIPS_CLIENT_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(TIPS_CLIENT_OBJS:.o=.dep)
+endif
+endif
+
+
+TIPS_CLIENT_TEST_SRC = \
+    examples/tips/client_test.cc \
+
+TIPS_CLIENT_TEST_OBJS = $(addprefix objs/$(CONFIG)/, $(addsuffix .o, $(basename $(TIPS_CLIENT_TEST_SRC))))
+
+ifeq ($(NO_SECURE),true)
+
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
+bins/$(CONFIG)/tips_client_test: openssl_dep_error
+
+else
+
+bins/$(CONFIG)/tips_client_test: $(TIPS_CLIENT_TEST_OBJS) libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a
+	$(E) "[LD]      Linking $@"
+	$(Q) mkdir -p `dirname $@`
+	$(Q) $(LDXX) $(LDFLAGS) $(TIPS_CLIENT_TEST_OBJS) $(GTEST_LIB) libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a $(LDLIBSXX) $(LDLIBS) $(LDLIBS_SECURE) -o bins/$(CONFIG)/tips_client_test
+
+endif
+
+objs/$(CONFIG)/examples/tips/client_test.o:  libs/$(CONFIG)/libtips_client_lib.a libs/$(CONFIG)/libgrpc++_test_util.a libs/$(CONFIG)/libgrpc_test_util.a libs/$(CONFIG)/libgrpc++.a libs/$(CONFIG)/libgrpc.a libs/$(CONFIG)/libgpr_test_util.a libs/$(CONFIG)/libgpr.a
+
+deps_tips_client_test: $(TIPS_CLIENT_TEST_OBJS:.o=.dep)
+
+ifneq ($(NO_SECURE),true)
+ifneq ($(NO_DEPS),true)
+-include $(TIPS_CLIENT_TEST_OBJS:.o=.dep)
+endif
+endif
+
+
 END2END_TEST_SRC = \
     test/cpp/end2end/end2end_test.cc \
 
@@ -5714,6 +5843,8 @@ CHTTP2_FAKE_SECURITY_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(addprefix objs/$(CON
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_fake_security_graceful_server_shutdown_test: openssl_dep_error
 
 else
@@ -6350,6 +6481,8 @@ CHTTP2_FULLSTACK_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(addprefix objs/$(CONFIG)
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_fullstack_graceful_server_shutdown_test: openssl_dep_error
 
 else
@@ -6986,6 +7119,8 @@ CHTTP2_SIMPLE_SSL_FULLSTACK_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(addprefix obj
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_simple_ssl_fullstack_graceful_server_shutdown_test: openssl_dep_error
 
 else
@@ -7622,6 +7757,8 @@ CHTTP2_SIMPLE_SSL_WITH_OAUTH2_FULLSTACK_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(a
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_simple_ssl_with_oauth2_fullstack_graceful_server_shutdown_test: openssl_dep_error
 
 else
@@ -8258,6 +8395,8 @@ CHTTP2_SOCKET_PAIR_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(addprefix objs/$(CONFI
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_socket_pair_graceful_server_shutdown_test: openssl_dep_error
 
 else
@@ -8894,6 +9033,8 @@ CHTTP2_SOCKET_PAIR_ONE_BYTE_AT_A_TIME_GRACEFUL_SERVER_SHUTDOWN_TEST_OBJS = $(add
 
 ifeq ($(NO_SECURE),true)
 
+# You can't build secure targets if you don't have OpenSSL with ALPN.
+
 bins/$(CONFIG)/chttp2_socket_pair_one_byte_at_a_time_graceful_server_shutdown_test: openssl_dep_error
 
 else
diff --git a/build.json b/build.json
index 1e465404a5..a3dea9c379 100644
--- a/build.json
+++ b/build.json
@@ -400,6 +400,22 @@
         "test/cpp/end2end/async_test_server.cc"
       ],
       "c++": true
+    },
+    {
+      "name": "tips_client_lib",
+      "build": "private",
+      "src": [
+        "examples/tips/label.proto",
+        "examples/tips/empty.proto",
+        "examples/tips/pubsub.proto",
+        "examples/tips/client.cc"
+      ],
+      "deps": [
+        "grpc++",
+        "grpc",
+        "gpr"
+      ],
+      "c++": true
     }
   ],
   "targets": [
@@ -1405,6 +1421,41 @@
       ]
     },
     {
+      "name": "tips_client",
+      "build": "test",
+      "run": false,
+      "c++": true,
+      "src": [
+        "examples/tips/client_main.cc"
+      ],
+      "deps": [
+        "tips_client_lib",
+        "grpc++_test_util",
+        "grpc_test_util",
+        "grpc++",
+        "grpc",
+        "gpr_test_util",
+        "gpr"
+      ]
+    },
+    {
+      "name": "tips_client_test",
+      "build": "test",
+      "c++": true,
+      "src": [
+        "examples/tips/client_test.cc"
+      ],
+      "deps": [
+        "tips_client_lib",
+        "grpc++_test_util",
+        "grpc_test_util",
+        "grpc++",
+        "grpc",
+        "gpr_test_util",
+        "gpr"
+      ]
+    },
+    {
       "name": "end2end_test",
       "build": "test",
       "c++": true,
diff --git a/examples/tips/client.cc b/examples/tips/client.cc
new file mode 100644
index 0000000000..bfbd59c9d5
--- /dev/null
+++ b/examples/tips/client.cc
@@ -0,0 +1,62 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <grpc++/client_context.h>
+
+#include "examples/tips/client.h"
+
+using grpc::ChannelInterface;
+using grpc::ClientContext;
+using tech::pubsub::Topic;
+using tech::pubsub::PublisherService;
+
+namespace grpc {
+namespace examples {
+namespace tips {
+
+Client::Client(std::shared_ptr<ChannelInterface> channel)
+    : stub_(PublisherService::NewStub(channel)) {
+}
+
+Status Client::CreateTopic(grpc::string topic) {
+  Topic request;
+  Topic response;
+  request.set_name(topic);
+  ClientContext context;
+
+  return stub_->CreateTopic(&context, request, &response);
+}
+
+}  // namesapce tips
+}  // namespace examples
+}  // namespace grpc
diff --git a/examples/tips/client.h b/examples/tips/client.h
new file mode 100644
index 0000000000..83e7911823
--- /dev/null
+++ b/examples/tips/client.h
@@ -0,0 +1,53 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <grpc++/channel_interface.h>
+#include <grpc++/status.h>
+#include "examples/tips/pubsub.pb.h"
+
+namespace grpc {
+namespace examples {
+namespace tips {
+
+class Client {
+ public:
+  Client(std::shared_ptr<grpc::ChannelInterface> channel);
+  Status CreateTopic(grpc::string topic);
+
+ private:
+  std::unique_ptr<tech::pubsub::PublisherService::Stub> stub_;
+};
+
+}  // namesapce tips
+}  // namespace examples
+}  // namespace grpc
diff --git a/examples/tips/client_main.cc b/examples/tips/client_main.cc
new file mode 100644
index 0000000000..0324b4b8b0
--- /dev/null
+++ b/examples/tips/client_main.cc
@@ -0,0 +1,85 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <chrono>
+#include <memory>
+#include <string>
+#include <thread>
+
+#include <grpc/grpc.h>
+#include <grpc/support/log.h>
+#include <google/gflags.h>
+#include <grpc++/channel_arguments.h>
+#include <grpc++/channel_interface.h>
+#include <grpc++/client_context.h>
+#include <grpc++/create_channel.h>
+#include <grpc++/status.h>
+#include <grpc++/stream.h>
+#include "test/cpp/util/create_test_channel.h"
+
+DEFINE_bool(enable_ssl, false, "Whether to use ssl/tls.");
+DEFINE_bool(use_prod_roots, false, "True to use SSL roots for production GFE");
+DEFINE_int32(server_port, 0, "Server port.");
+DEFINE_string(server_host, "127.0.0.1", "Server host to connect to");
+DEFINE_string(server_host_override, "foo.test.google.com",
+              "Override the server host which is sent in HTTP header");
+
+using grpc::ChannelInterface;
+using grpc::ClientContext;
+using grpc::CreateTestChannel;
+
+void CreateTopic(std::shared_ptr<ChannelInterface> channel, grpc::string topic);
+
+int main(int argc, char** argv) {
+  grpc_init();
+
+  google::ParseCommandLineFlags(&argc, &argv, true);
+
+  gpr_log(GPR_INFO, "Start TIPS client");
+
+  GPR_ASSERT(FLAGS_server_port);
+  const int host_port_buf_size = 1024;
+  char host_port[host_port_buf_size];
+  snprintf(host_port, host_port_buf_size, "%s:%d", FLAGS_server_host.c_str(),
+           FLAGS_server_port);
+
+  std::shared_ptr<ChannelInterface> channel(
+      CreateTestChannel(host_port, FLAGS_server_host_override, FLAGS_enable_ssl,
+                        FLAGS_use_prod_roots));
+
+  CreateTopic(channel, "test");
+
+  channel.reset();
+  grpc_shutdown();
+  return 0;
+}
diff --git a/examples/tips/client_test.cc b/examples/tips/client_test.cc
new file mode 100644
index 0000000000..d40f0c0d8b
--- /dev/null
+++ b/examples/tips/client_test.cc
@@ -0,0 +1,110 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <grpc++/channel_arguments.h>
+#include <grpc++/channel_interface.h>
+#include <grpc++/client_context.h>
+#include <grpc++/create_channel.h>
+#include <grpc++/server.h>
+#include <grpc++/server_builder.h>
+#include <grpc++/server_context.h>
+#include <grpc++/status.h>
+#include <gtest/gtest.h>
+
+#include "examples/tips/client.h"
+#include "test/core/util/port.h"
+#include "test/core/util/test_config.h"
+
+using grpc::ChannelInterface;
+
+namespace {
+
+}  //
+
+namespace grpc {
+namespace testing {
+namespace {
+
+const char kTopic[] = "test topic";
+
+class PublishServiceImpl : public tech::pubsub::PublisherService::Service {
+ public:
+  Status CreateTopic(::grpc::ServerContext* context,
+                     const ::tech::pubsub::Topic* request,
+                     ::tech::pubsub::Topic* response) override {
+    EXPECT_EQ(request->name(), kTopic);
+    return Status::OK;
+  }
+};
+
+class End2endTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    int port = grpc_pick_unused_port_or_die();
+    server_address_ << "localhost:" << port;
+    // Setup server
+    ServerBuilder builder;
+    builder.AddPort(server_address_.str());
+    builder.RegisterService(service_.service());
+    server_ = builder.BuildAndStart();
+
+    channel_ = CreateChannel(server_address_.str(), ChannelArguments());
+  }
+
+  void TearDown() override { server_->Shutdown(); }
+
+  std::unique_ptr<Server> server_;
+  std::ostringstream server_address_;
+  PublishServiceImpl service_;
+
+  std::shared_ptr<ChannelInterface> channel_;
+};
+
+TEST_F(End2endTest, CreateTopic) {
+  grpc::examples::tips::Client client(channel_);
+  client.CreateTopic(kTopic);
+}
+
+}  // namespace
+}  // namespace testing
+}  // namespace grpc
+
+int main(int argc, char** argv) {
+  grpc_test_init(argc, argv);
+  grpc_init();
+  ::testing::InitGoogleTest(&argc, argv);
+  gpr_log(GPR_INFO, "Start test ...");
+  int result = RUN_ALL_TESTS();
+  grpc_shutdown();
+  return result;
+}
diff --git a/examples/tips/empty.proto b/examples/tips/empty.proto
new file mode 100644
index 0000000000..a698ab6f8a
--- /dev/null
+++ b/examples/tips/empty.proto
@@ -0,0 +1,19 @@
+syntax = "proto2";
+
+package proto2;
+
+// An empty message that you can re-use to avoid defining duplicated empty
+// messages in your project. A typical example is to use it as argument or the
+// return value of a service API. For instance:
+//
+//   service Foo {
+//     rpc Bar (proto2.Empty) returns (proto2.Empty) { };
+//   };
+//
+// BEGIN GOOGLE-INTERNAL
+// The difference between this one and net/rpc/empty-message.proto is that
+// 1) The generated message here is in proto2 C++ API.
+// 2) The proto2.Empty has minimum dependencies
+//    (no message_set or net/rpc dependencies)
+// END GOOGLE-INTERNAL
+message Empty {}
diff --git a/examples/tips/label.proto b/examples/tips/label.proto
new file mode 100644
index 0000000000..e79e1db77c
--- /dev/null
+++ b/examples/tips/label.proto
@@ -0,0 +1,49 @@
+// Labels provide a way to associate user-defined metadata with various
+// objects.  Labels may be used to organize objects into non-hierarchical
+// groups; think metadata tags attached to mp3s.  For more details, see
+// http://go/exosphere:labels
+
+syntax = "proto2";
+
+package tech.label;
+
+// A key-value pair applied to a given object.
+message Label {
+  // The key of a label is a syntactically valid URL (as per RFC 1738) with
+  // the "scheme" and initial slashes omitted and with the additional
+  // restrictions noted below.  Each key should be globally unique.  The
+  // "host" portion is called the "namespace" and is not necessarily
+  // resolvable to a network endpoint.  Instead, the namespace indicates what
+  // system or entity defines the semantics of the label.  Namespaces do not
+  // restrict the set of objects to which a label may be associated.
+  //
+  // Keys are defined by the following grammar:
+  //
+  //   key          = hostname "/" kpath
+  //   kpath        = ksegment *[ "/" ksegment ]
+  //   ksegment     = alphadigit | *[ alphadigit | "-" | "_" | "." ]
+  //
+  // where "hostname" and "alphadigit" are defined as in RFC 1738.
+  //
+  // Example key:
+  //   spanner.google.com/universe
+  required string key = 1;
+
+  // The value of the label.
+  oneof value {
+    // A string value.
+    string str_value = 2;
+    // An integer value.
+    int64 num_value = 3;
+  }
+}
+
+// A collection of labels, such as the set of all labels attached to an
+// object.  Each label in the set must have a different key.
+//
+// Users should prefer to embed "repeated Label" directly when possible.
+// This message should only be used in cases where that isn't possible (e.g.
+// with oneof).
+message Labels {
+  repeated Label label = 1;
+}
diff --git a/examples/tips/messages.proto b/examples/tips/messages.proto
new file mode 100644
index 0000000000..29db0dd8b1
--- /dev/null
+++ b/examples/tips/messages.proto
@@ -0,0 +1,94 @@
+// Message definitions to be used by integration test service definitions.
+
+syntax = "proto2";
+
+package grpc.testing;
+
+// The type of payload that should be returned.
+enum PayloadType {
+  // Compressable text format.
+  COMPRESSABLE = 0;
+
+  // Uncompressable binary format.
+  UNCOMPRESSABLE = 1;
+
+  // Randomly chosen from all other formats defined in this enum.
+  RANDOM = 2;
+}
+
+// A block of data, to simply increase gRPC message size.
+message Payload {
+  // The type of data in body.
+  optional PayloadType type = 1;
+  // Primary contents of payload.
+  optional bytes body = 2;
+}
+
+// Unary request.
+message SimpleRequest {
+  // Desired payload type in the response from the server.
+  // If response_type is RANDOM, server randomly chooses one from other formats.
+  optional PayloadType response_type = 1;
+
+  // Desired payload size in the response from the server.
+  // If response_type is COMPRESSABLE, this denotes the size before compression.
+  optional int32 response_size = 2;
+
+  // Optional input payload sent along with the request.
+  optional Payload payload = 3;
+}
+
+// Unary response, as configured by the request.
+message SimpleResponse {
+  // Payload to increase message size.
+  optional Payload payload = 1;
+  // The user the request came from, for verifying authentication was
+  // successful when the client expected it.
+  optional int64 effective_gaia_user_id = 2;
+}
+
+// Client-streaming request.
+message StreamingInputCallRequest {
+  // Optional input payload sent along with the request.
+  optional Payload payload = 1;
+
+  // Not expecting any payload from the response.
+}
+
+// Client-streaming response.
+message StreamingInputCallResponse {
+  // Aggregated size of payloads received from the client.
+  optional int32 aggregated_payload_size = 1;
+}
+
+// Configuration for a particular response.
+message ResponseParameters {
+  // Desired payload sizes in responses from the server.
+  // If response_type is COMPRESSABLE, this denotes the size before compression.
+  optional int32 size = 1;
+
+  // Desired interval between consecutive responses in the response stream in
+  // microseconds.
+  optional int32 interval_us = 2;
+}
+
+// Server-streaming request.
+message StreamingOutputCallRequest {
+  // Desired payload type in the response from the server.
+  // If response_type is RANDOM, the payload from each response in the stream
+  // might be of different types. This is to simulate a mixed type of payload
+  // stream.
+  optional PayloadType response_type = 1;
+
+  // Configuration for each expected response message.
+  repeated ResponseParameters response_parameters = 2;
+
+  // Optional input payload sent along with the request.
+  optional Payload payload = 3;
+}
+
+// Server-streaming response, as configured by the request and parameters.
+message StreamingOutputCallResponse {
+  // Payload to increase response size.
+  optional Payload payload = 1;
+}
diff --git a/examples/tips/pubsub.proto b/examples/tips/pubsub.proto
new file mode 100644
index 0000000000..0b3bd5d012
--- /dev/null
+++ b/examples/tips/pubsub.proto
@@ -0,0 +1,702 @@
+// Specification of the Pubsub API.
+
+syntax = "proto2";
+
+import "examples/tips/empty.proto";
+import "examples/tips/label.proto";
+
+package tech.pubsub;
+
+// -----------------------------------------------------------------------------
+// Overview of the Pubsub API
+// -----------------------------------------------------------------------------
+
+// This file describes an API for a Pubsub system.  This system provides a
+// reliable many-to-many communication mechanism between independently written
+// publishers and subscribers where the publisher publishes messages to "topics"
+// and each subscriber creates a "subscription" and consumes messages from it.
+//
+// (a) The pubsub system maintains bindings between topics and subscriptions.
+// (b) A publisher publishes messages into a topic.
+// (c) The pubsub system delivers messages from topics into relevant
+//     subscriptions.
+// (d) A subscriber receives pending messages from its subscription and
+//     acknowledges or nacks each one to the pubsub system.
+// (e) The pubsub system removes acknowledged messages from that subscription.
+
+// -----------------------------------------------------------------------------
+// Data Model
+// -----------------------------------------------------------------------------
+
+// The data model consists of the following:
+//
+// * Topic: A topic is a resource to which messages are published by publishers.
+//     Topics are named, and the name of the topic is unique within the pubsub
+//     system.
+//
+// * Subscription: A subscription records the subscriber's interest in a topic.
+//     It can optionally include a query to select a subset of interesting
+//     messages.  The pubsub system maintains a logical cursor tracking the
+//     matching messages which still need to be delivered and acked so that
+//     they can retried as needed.  The set of messages that have not been
+//     acknowledged is called the subscription backlog.
+//
+// * Message: A message is a unit of data that flows in the system.  It contains
+//     opaque data from the publisher along with its labels.
+//
+// * Message Labels (optional): A set of opaque key, value pairs assigned
+//     by the publisher which the subscriber can use for filtering out messages
+//     in the topic.  For example, a label with key "foo.com/device_type" and
+//     value "mobile" may be added for messages that are only relevant for a
+//     mobile subscriber; a subscriber on a phone may decide to create a
+//     subscription only for messages that have this label.
+
+// -----------------------------------------------------------------------------
+// Publisher Flow
+// -----------------------------------------------------------------------------
+
+// A publisher publishes messages to the topic using the Publish request:
+//
+//   PubsubMessage message;
+//   message.set_data("....");
+//   Label label;
+//   label.set_key("foo.com/key1");
+//   label.set_str_value("value1");
+//   message.add_label(label);
+//   PublishRequest request;
+//   request.set_topic("topicName");
+//   request.set_message(message);
+//   PublisherService.Publish(request);
+
+// -----------------------------------------------------------------------------
+// Subscriber Flow
+// -----------------------------------------------------------------------------
+
+// The subscriber part of the API is richer than the publisher part and has a
+// number of concepts w.r.t. subscription creation and monitoring:
+//
+// (1) A subscriber creates a subscription using the CreateSubscription call.
+//     It may specify an optional "query" to indicate that it wants to receive
+//     only messages with a certain set of labels using the label query syntax.
+//     It may also specify an optional truncation policy to indicate when old
+//     messages from the subcription can be removed.
+//
+// (2) A subscriber receives messages in one of two ways: via push or pull.
+//
+// (a) To receive messages via push, the PushConfig field must be specified in
+//     the Subscription parameter when creating a subscription.  The PushConfig
+//     specifies an endpoint at which the subscriber must expose the
+//     PushEndpointService.  Messages are received via the HandlePubsubEvent
+//     method.  The push subscriber responds to the HandlePubsubEvent method
+//     with a result code that indicates one of three things: Ack (the message
+//     has been successfully processed and the Pubsub system may delete it),
+//     Nack (the message has been rejected, the Pubsub system should resend it
+//     at a later time), or Push-Back (this is a Nack with the additional
+//     semantics that the subscriber is overloaded and the pubsub system should
+//     back off on the rate at which it is invoking HandlePubsubEvent).  The
+//     endpoint may be a load balancer for better scalability.
+//
+// (b) To receive messages via pull a subscriber calls the Pull method on the
+//     SubscriberService to get messages from the subscription.  For each
+//     individual message, the subscriber may use the ack_id received in the
+//     PullResponse to Ack the message, Nack the message, or modify the ack
+//     deadline with ModifyAckDeadline.  See the
+//     Subscription.ack_deadline_seconds field documentation for details on the
+//     ack deadline behavior.
+//
+//     Note: Messages may be consumed in parallel by multiple subscribers making
+//       Pull calls to the same subscription; this will result in the set of
+//       messages from the subscription being shared and each subscriber
+//       receiving a subset of the messages.
+//
+// (4) The subscriber can explicitly truncate the current subscription.
+//
+// (5) "Truncated" events are delivered when a subscription is
+//     truncated, whether due to the subscription's truncation policy
+//     or an explicit request from the subscriber.
+//
+// Subscription creation:
+//
+//   Subscription subscription;
+//   subscription.set_topic("topicName");
+//   subscription.set_name("subscriptionName");
+//   subscription.push_config().set_push_endpoint("machinename:8888");
+//   SubscriberService.CreateSubscription(subscription);
+//
+// Consuming messages via push:
+//
+//  TODO(eschapira): Add HTTP push example.
+//
+//  The port 'machinename:8888' must be bound to a stubby server that implements
+//  the PushEndpointService with the following method:
+//
+//   int HandlePubsubEvent(PubsubEvent event) {
+//     if (event.subscription().equals("subscriptionName")) {
+//       if (event.has_message()) {
+//         Process(event.message().data());
+//       } else if (event.truncated()) {
+//         ProcessTruncatedEvent();
+//       }
+//     }
+//     return OK;  // This return code implies an acknowledgment
+//   }
+//
+// Consuming messages via pull:
+//
+//  The subscription must be created without setting the push_config field.
+//
+//   PullRequest pull_request;
+//   pull_request.set_subscription("subscriptionName");
+//   pull_request.set_return_immediately(false);
+//   while (true) {
+//     PullResponse pull_response;
+//     if (SubscriberService.Pull(pull_request, pull_response) == OK) {
+//       PubsubEvent event = pull_response.pubsub_event();
+//       if (event.has_message()) {
+//         Process(event.message().data());
+//       } else if (event.truncated()) {
+//         ProcessTruncatedEvent();
+//       }
+//       AcknowledgeRequest ack_request;
+//       ackRequest.set_subscription("subscriptionName");
+//       ackRequest.set_ack_id(pull_response.ack_id());
+//       SubscriberService.Acknowledge(ack_request);
+//     }
+//   }
+
+// -----------------------------------------------------------------------------
+// Reliability Semantics
+// -----------------------------------------------------------------------------
+
+// When a subscriber successfully creates a subscription using
+// Subscriber.CreateSubscription, it establishes a "subscription point" with
+// respect to that subscription - the subscriber is guaranteed to receive any
+// message published after this subscription point that matches the
+// subscription's query.  Note that messages published before the Subscription
+// point may or may not be delivered.
+//
+// If the system truncates the subscription according to the specified
+// truncation policy, the system delivers a subscription status event with the
+// "truncated" field set to true.  We refer to such events as "truncation
+// events".  A truncation event:
+//
+// * Informs the subscriber that part of the subscription messages have been
+//   discarded.  The subscriber may want to recover from the message loss, e.g.,
+//   by resyncing its state with its backend.
+// * Establishes a new subscription point, i.e., the subscriber is guaranteed to
+//   receive all changes published after the trunction event is received (or
+//   until another truncation event is received).
+//
+// Note that messages are not delivered in any particular order by the pubsub
+// system.  Furthermore, the system guarantees at-least-once delivery
+// of each message or truncation events until acked.
+
+// -----------------------------------------------------------------------------
+// Deletion
+// -----------------------------------------------------------------------------
+
+// Both topics and subscriptions may be deleted.  Deletion of a topic implies
+// deletion of all attached subscriptions.
+//
+// When a subscription is deleted directly by calling DeleteSubscription, all
+// messages are immediately dropped.  If it is a pull subscriber, future pull
+// requests will return NOT_FOUND.
+//
+// When a topic is deleted all corresponding subscriptions are immediately
+// deleted, and subscribers experience the same behavior as directly deleting
+// the subscription.
+
+// -----------------------------------------------------------------------------
+// The Publisher service and its protos.
+// -----------------------------------------------------------------------------
+
+// The service that an application uses to manipulate topics, and to send
+// messages to a topic.
+service PublisherService {
+
+  // Creates the given topic with the given name.
+  rpc CreateTopic(Topic) returns (Topic) {
+  }
+
+  // Adds a message to the topic.  Returns NOT_FOUND if the topic does not
+  // exist.
+  // (-- For different error code values returned via Stubby, see
+  // util/task/codes.proto. --)
+  rpc Publish(PublishRequest) returns (proto2.Empty) {
+  }
+
+  // Adds one or more messages to the topic. Returns NOT_FOUND if the topic does
+  // not exist.
+  rpc PublishBatch(PublishBatchRequest) returns (PublishBatchResponse) {
+  }
+
+  // Gets the configuration of a topic. Since the topic only has the name
+  // attribute, this method is only useful to check the existence of a topic.
+  // If other attributes are added in the future, they will be returned here.
+  rpc GetTopic(GetTopicRequest) returns (Topic) {
+  }
+
+  // Lists matching topics.
+  rpc ListTopics(ListTopicsRequest) returns (ListTopicsResponse) {
+  }
+
+  // Deletes the topic with the given name.  All subscriptions to this topic
+  // are also deleted. Returns NOT_FOUND if the topic does not exist.
+  // After a topic is deleted, a new topic may be created with the same name.
+  rpc DeleteTopic(DeleteTopicRequest) returns (proto2.Empty)  {
+  }
+}
+
+// A topic resource.
+message Topic {
+  // Name of the topic.
+  optional string name = 1;
+}
+
+// A message data and its labels.
+message PubsubMessage {
+  // The message payload.
+  optional bytes data = 1;
+
+  // Optional list of labels for this message. Keys in this collection must
+  // be unique.
+  //(-- TODO(eschapira): Define how key namespace may be scoped to the topic.--)
+  repeated tech.label.Label label = 2;
+
+  // ID of this message assigned by the server at publication time. Guaranteed
+  // to be unique within the topic. This value may be read by a subscriber
+  // that receives a PubsubMessage via a Pull call or a push delivery. It must
+  // not be populated by a publisher in a Publish call.
+  optional string message_id = 3;
+}
+
+// Request for the GetTopic method.
+message GetTopicRequest {
+  // The name of the topic to get.
+  optional string topic = 1;
+}
+
+// Request for the Publish method.
+message PublishRequest {
+  // The message in the request will be published on this topic.
+  optional string topic = 1;
+
+  // The message to publish.
+  optional PubsubMessage message = 2;
+}
+
+// Request for the PublishBatch method.
+message PublishBatchRequest {
+  // The messages in the request will be published on this topic.
+  optional string topic = 1;
+
+  // The messages to publish.
+  repeated PubsubMessage messages = 2;
+}
+
+// Response for the PublishBatch method.
+message PublishBatchResponse {
+  // The server-assigned ID of each published message, in the same order as
+  // the messages in the request. IDs are guaranteed to be unique within
+  // the topic.
+  repeated string message_ids = 1;
+}
+
+// Request for the ListTopics method.
+message ListTopicsRequest {
+  // A valid label query expression.
+  // (-- Which labels are required or supported is implementation-specific. --)
+  optional string query = 1;
+
+  // Maximum number of topics to return.
+  // (-- If not specified or <= 0, the implementation will select a reasonable
+  // value. --)
+  optional int32 max_results = 2;
+
+  // The value obtained in the last <code>ListTopicsResponse</code>
+  // for continuation.
+  optional string page_token = 3;
+
+}
+
+// Response for the ListTopics method.
+message ListTopicsResponse {
+  // The resulting topics.
+  repeated Topic topic = 1;
+
+  // If not empty, indicates that there are more topics that match the request,
+  // and this value should be passed to the next <code>ListTopicsRequest</code>
+  // to continue.
+  optional string next_page_token = 2;
+}
+
+// Request for the Delete method.
+message DeleteTopicRequest {
+  // Name of the topic to delete.
+  optional string topic = 1;
+}
+
+// -----------------------------------------------------------------------------
+// The Subscriber service and its protos.
+// -----------------------------------------------------------------------------
+
+// The service that an application uses to manipulate subscriptions and to
+// consume messages from a subscription via the pull method.
+service SubscriberService {
+
+  // Creates a subscription on a given topic for a given subscriber.
+  // If the subscription already exists, returns ALREADY_EXISTS.
+  // If the corresponding topic doesn't exist, returns NOT_FOUND.
+  //
+  // If the name is not provided in the request, the server will assign a random
+  // name for this subscription on the same project as the topic.
+  rpc CreateSubscription(Subscription) returns (Subscription) {
+  }
+
+  // Gets the configuration details of a subscription.
+  rpc GetSubscription(GetSubscriptionRequest) returns (Subscription) {
+  }
+
+  // Lists matching subscriptions.
+  rpc ListSubscriptions(ListSubscriptionsRequest)
+      returns (ListSubscriptionsResponse) {
+  }
+
+  // Deletes an existing subscription. All pending messages in the subscription
+  // are immediately dropped. Calls to Pull after deletion will return
+  // NOT_FOUND.
+  rpc DeleteSubscription(DeleteSubscriptionRequest) returns (proto2.Empty) {
+  }
+
+  // Removes all the pending messages in the subscription and releases the
+  // storage associated with them. Results in a truncation event to be sent to
+  // the subscriber. Messages added after this call returns are stored in the
+  // subscription as before.
+  rpc TruncateSubscription(TruncateSubscriptionRequest) returns (proto2.Empty) {
+  }
+
+  //
+  // Push subscriber calls.
+  //
+
+  // Modifies the <code>PushConfig</code> for a specified subscription.
+  // This method can be used to suspend the flow of messages to an endpoint
+  // by clearing the <code>PushConfig</code> field in the request. Messages
+  // will be accumulated for delivery even if no push configuration is
+  // defined or while the configuration is modified.
+  rpc ModifyPushConfig(ModifyPushConfigRequest) returns (proto2.Empty) {
+  }
+
+  //
+  // Pull Subscriber calls
+  //
+
+  // Pulls a single message from the server.
+  // If return_immediately is true, and no messages are available in the
+  // subscription, this method returns FAILED_PRECONDITION. The system is free
+  // to return an UNAVAILABLE error if no messages are available in a
+  // reasonable amount of time (to reduce system load).
+  rpc Pull(PullRequest) returns (PullResponse) {
+  }
+
+  // Pulls messages from the server. Returns an empty list if there are no
+  // messages available in the backlog. The system is free to return UNAVAILABLE
+  // if there are too many pull requests outstanding for the given subscription.
+  rpc PullBatch(PullBatchRequest) returns (PullBatchResponse) {
+  }
+
+  // Modifies the Ack deadline for a message received from a pull request.
+  rpc ModifyAckDeadline(ModifyAckDeadlineRequest) returns (proto2.Empty) {
+  }
+
+  // Acknowledges a particular received message: the Pub/Sub system can remove
+  // the given message from the subscription. Acknowledging a message whose
+  // Ack deadline has expired may succeed, but the message could have been
+  // already redelivered. Acknowledging a message more than once will not
+  // result in an error. This is only used for messages received via pull.
+  rpc Acknowledge(AcknowledgeRequest) returns (proto2.Empty) {
+  }
+
+  // Refuses processing a particular received message. The system will
+  // redeliver this message to some consumer of the subscription at some
+  // future time. This is only used for messages received via pull.
+  rpc Nack(NackRequest) returns (proto2.Empty) {
+  }
+}
+
+// A subscription resource.
+message Subscription {
+  // Name of the subscription.
+  optional string name = 1;
+
+  // The name of the topic from which this subscription is receiving messages.
+  optional string topic = 2;
+
+  // If <code>query</code> is non-empty, only messages on the subscriber's
+  // topic whose labels match the query will be returned. Otherwise all
+  // messages on the topic will be returned.
+  // (-- The query syntax is described in tech/label/proto/label_query.proto --)
+  optional string query = 3;
+
+  // The subscriber may specify requirements for truncating unacknowledged
+  // subscription entries. The system will honor the
+  // <code>CreateSubscription</code> request only if it can meet these
+  // requirements. If this field is not specified, messages are never truncated
+  // by the system.
+  optional TruncationPolicy truncation_policy = 4;
+
+  // Specifies which messages can be truncated by the system.
+  message TruncationPolicy {
+    oneof policy {
+      // If <code>max_bytes</code> is specified, the system is allowed to drop
+      // old messages to keep the combined size of stored messages under
+      // <code>max_bytes</code>. This is a hint; the system may keep more than
+      // this many bytes, but will make a best effort to keep the size from
+      // growing much beyond this parameter.
+      int64 max_bytes = 1;
+
+      // If <code>max_age_seconds</code> is specified, the system is allowed to
+      // drop messages that have been stored for at least this many seconds.
+      // This is a hint; the system may keep these messages, but will make a
+      // best effort to remove them when their maximum age is reached.
+      int64 max_age_seconds = 2;
+    }
+  }
+
+  // If push delivery is used with this subscription, this field is
+  // used to configure it.
+  optional PushConfig push_config = 5;
+
+  // For either push or pull delivery, the value is the maximum time after a
+  // subscriber receives a message before the subscriber should acknowledge or
+  // Nack the message. If the Ack deadline for a message passes without an
+  // Ack or a Nack, the Pub/Sub system will eventually redeliver the message.
+  // If a subscriber acknowledges after the deadline, the Pub/Sub system may
+  // accept the Ack, but it is possible that the message has been already
+  // delivered again. Multiple Acks to the message are allowed and will
+  // succeed.
+  //
+  // For push delivery, this value is used to set the request timeout for
+  // the call to the push endpoint.
+  //
+  // For pull delivery, this value is used as the initial value for the Ack
+  // deadline. It may be overridden for a specific pull request (message) with
+  // <code>ModifyAckDeadline</code>.
+  // While a message is outstanding (i.e. it has been delivered to a pull
+  // subscriber and the subscriber has not yet Acked or Nacked), the Pub/Sub
+  // system will not deliver that message to another pull subscriber
+  // (on a best-effort basis).
+  optional int32 ack_deadline_seconds = 6;
+
+  // If this parameter is set to n, the system is allowed to (but not required
+  // to) delete the subscription when at least n seconds have elapsed since the
+  // client presence was detected. (Presence is detected through any
+  // interaction using the subscription ID, including Pull(), Get(), or
+  // acknowledging a message.)
+  //
+  // If this parameter is not set, the subscription will stay live until
+  // explicitly deleted.
+  //
+  // Clients can detect such garbage collection when a Get call or a Pull call
+  // (for pull subscribers only) returns NOT_FOUND.
+  optional int64 garbage_collect_seconds = 7;
+}
+
+// Configuration for a push delivery endpoint.
+message PushConfig {
+  // A URL locating the endpoint to which messages should be pushed.
+  // For example, a Webhook endpoint might use "https://example.com/push".
+  // (-- An Android application might use "gcm:<REGID>", where <REGID> is a
+  // GCM registration id allocated for pushing messages to the application. --)
+  optional string push_endpoint = 1;
+}
+
+// An event indicating a received message or truncation event.
+message PubsubEvent {
+  // The subscription that received the event.
+  optional string subscription = 1;
+
+  oneof type {
+    // A received message.
+    PubsubMessage message = 2;
+
+    // Indicates that this subscription has been truncated.
+    bool truncated = 3;
+
+    // Indicates that this subscription has been deleted. (Note that pull
+    // subscribers will always receive NOT_FOUND in response in their pull
+    // request on the subscription, rather than seeing this boolean.)
+    bool deleted = 4;
+  }
+}
+
+// Request for the GetSubscription method.
+message GetSubscriptionRequest {
+  // The name of the subscription to get.
+  optional string subscription = 1;
+}
+
+// Request for the ListSubscriptions method.
+message ListSubscriptionsRequest {
+  // A valid label query expression.
+  // (-- Which labels are required or supported is implementation-specific.
+  // TODO(eschapira): This method must support to query by topic. We must
+  // define the key URI for the "topic" label. --)
+  optional string query = 1;
+
+  // Maximum number of subscriptions to return.
+  // (-- If not specified or <= 0, the implementation will select a reasonable
+  // value. --)
+  optional int32 max_results = 3;
+
+  // The value obtained in the last <code>ListSubscriptionsResponse</code>
+  // for continuation.
+  optional string page_token = 4;
+}
+
+// Response for the ListSubscriptions method.
+message ListSubscriptionsResponse {
+  // The subscriptions that match the request.
+  repeated Subscription subscription = 1;
+
+  // If not empty, indicates that there are more subscriptions that match the
+  // request and this value should be passed to the next
+  // <code>ListSubscriptionsRequest</code> to continue.
+  optional string next_page_token = 2;
+}
+
+// Request for the TruncateSubscription method.
+message TruncateSubscriptionRequest {
+  // The subscription that is being truncated.
+  optional string subscription = 1;
+}
+
+// Request for the DeleteSubscription method.
+message DeleteSubscriptionRequest {
+  // The subscription to delete.
+  optional string subscription = 1;
+}
+
+// Request for the ModifyPushConfig method.
+message ModifyPushConfigRequest {
+  // The name of the subscription.
+  optional string subscription = 1;
+
+  // An empty <code>push_config</code> indicates that the Pub/Sub system should
+  // pause pushing messages from the given subscription.
+  optional PushConfig push_config = 2;
+}
+
+// -----------------------------------------------------------------------------
+// The protos used by a pull subscriber.
+// -----------------------------------------------------------------------------
+
+// Request for the Pull method.
+message PullRequest {
+  // The subscription from which a message should be pulled.
+  optional string subscription = 1;
+
+  // If this is specified as true the system will respond immediately even if
+  // it is not able to return a message in the Pull response. Otherwise the
+  // system is allowed to wait until at least one message is available rather
+  // than returning FAILED_PRECONDITION. The client may cancel the request if
+  // it does not wish to wait any longer for the response.
+  optional bool return_immediately = 2;
+}
+
+// Either a <code>PubsubMessage</code> or a truncation event. One of these two
+// must be populated.
+message PullResponse {
+  // This ID must be used to acknowledge the received event or message.
+  optional string ack_id = 1;
+
+  // A pubsub message or truncation event.
+  optional PubsubEvent pubsub_event = 2;
+}
+
+// Request for the PullBatch method.
+message PullBatchRequest {
+  // The subscription from which messages should be pulled.
+  optional string subscription = 1;
+
+  // If this is specified as true the system will respond immediately even if
+  // it is not able to return a message in the Pull response. Otherwise the
+  // system is allowed to wait until at least one message is available rather
+  // than returning no messages. The client may cancel the request if it does
+  // not wish to wait any longer for the response.
+  optional bool return_immediately = 2;
+
+  // The maximum number of PubsubEvents returned for this request. The Pub/Sub
+  // system may return fewer than the number of events specified.
+  optional int32 max_events = 3;
+}
+
+// Response for the PullBatch method.
+message PullBatchResponse {
+
+  // Received Pub/Sub messages or status events. The Pub/Sub system will return
+  // zero messages if there are no more messages available in the backlog. The
+  // Pub/Sub system may return fewer than the max_events requested even if
+  // there are more messages available in the backlog.
+  repeated PullResponse pull_responses = 2;
+}
+
+// Request for the ModifyAckDeadline method.
+message ModifyAckDeadlineRequest {
+  // The name of the subscription from which messages are being pulled.
+  optional string subscription = 1;
+
+  // The acknowledgment ID.
+  optional string ack_id = 2;
+
+  // The new Ack deadline. Must be >= 0.
+  optional int32 ack_deadline_seconds = 3;
+}
+
+// Request for the Acknowledge method.
+message AcknowledgeRequest {
+  // The subscription whose message is being acknowledged.
+  optional string subscription = 1;
+
+  // The acknowledgment ID for the message being acknowledged. This was
+  // returned by the Pub/Sub system in the Pull response.
+  repeated string ack_id = 2;
+}
+
+// Request for the Nack method.
+message NackRequest {
+  // The subscription whose message is being Nacked.
+  optional string subscription = 1;
+
+  // The acknowledgment ID for the message being refused. This was returned by
+  // the Pub/Sub system in the Pull response.
+  repeated string ack_id = 2;
+}
+
+// -----------------------------------------------------------------------------
+// The service and protos used by a push subscriber.
+// -----------------------------------------------------------------------------
+
+// The service that a subscriber uses to handle messages sent via push
+// delivery.
+// This service is not currently exported for HTTP clients.
+// TODO(eschapira): Explain HTTP subscribers.
+service PushEndpointService {
+  // Sends a <code>PubsubMessage</code> or a subscription status event to a
+  // push endpoint.
+  // The push endpoint responds with an empty message and a code from
+  // util/task/codes.proto. The following codes have a particular meaning to the
+  // Pub/Sub system:
+  // OK          - This is interpreted by Pub/Sub as Ack.
+  // ABORTED     - This is intepreted by Pub/Sub as a Nack, without implying
+  //               pushback for congestion control.  The Pub/Sub system will
+  //               retry this message at a later time.
+  // UNAVAILABLE - This is intepreted by Pub/Sub as a Nack, with the additional
+  //               semantics of push-back.  The Pub/Sub system will use an AIMD
+  //               congestion control algorithm to backoff the rate of sending
+  //               messages from this subscription.
+  // Any other code, or a failure to respond, will be interpreted in the same
+  // way as ABORTED; i.e. the system will retry the message at a later time to
+  // ensure reliable delivery.
+  rpc HandlePubsubEvent(PubsubEvent) returns (proto2.Empty);
+}
diff --git a/examples/tips/server.cc b/examples/tips/server.cc
new file mode 100644
index 0000000000..2171a6aac0
--- /dev/null
+++ b/examples/tips/server.cc
@@ -0,0 +1,231 @@
+/*
+ *
+ * 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.
+ *
+ */
+
+#include <memory>
+#include <sstream>
+#include <thread>
+
+#include <google/gflags.h>
+#include <grpc/grpc.h>
+#include <grpc/support/log.h>
+#include "test/core/end2end/data/ssl_test_data.h"
+#include <grpc++/config.h>
+#include <grpc++/server.h>
+#include <grpc++/server_builder.h>
+#include <grpc++/server_context.h>
+#include <grpc++/server_credentials.h>
+#include <grpc++/status.h>
+#include <grpc++/stream.h>
+#include "examples/tips/test.pb.h"
+#include "examples/tips/empty.pb.h"
+#include "examples/tips/messages.pb.h"
+
+DEFINE_bool(enable_ssl, false, "Whether to use ssl/tls.");
+DEFINE_int32(port, 0, "Server port.");
+
+using grpc::Server;
+using grpc::ServerBuilder;
+using grpc::ServerContext;
+using grpc::ServerCredentials;
+using grpc::ServerCredentialsFactory;
+using grpc::ServerReader;
+using grpc::ServerReaderWriter;
+using grpc::ServerWriter;
+using grpc::SslServerCredentialsOptions;
+using grpc::testing::Payload;
+using grpc::testing::PayloadType;
+using grpc::testing::SimpleRequest;
+using grpc::testing::SimpleResponse;
+using grpc::testing::StreamingInputCallRequest;
+using grpc::testing::StreamingInputCallResponse;
+using grpc::testing::StreamingOutputCallRequest;
+using grpc::testing::StreamingOutputCallResponse;
+using grpc::testing::TestService;
+using grpc::Status;
+
+bool SetPayload(PayloadType type, int size, Payload* payload) {
+  PayloadType response_type = type;
+  // TODO(yangg): Support UNCOMPRESSABLE payload.
+  if (type != PayloadType::COMPRESSABLE) {
+    return false;
+  }
+  payload->set_type(response_type);
+  std::unique_ptr<char[]> body(new char[size]());
+  payload->set_body(body.get(), size);
+  return true;
+}
+
+class TestServiceImpl : public TestService::Service {
+ public:
+  Status EmptyCall(ServerContext* context, const grpc::testing::Empty* request,
+                   grpc::testing::Empty* response) {
+    return Status::OK;
+  }
+
+  Status UnaryCall(ServerContext* context, const SimpleRequest* request,
+                   SimpleResponse* response) {
+    if (request->has_response_size() && request->response_size() > 0) {
+      if (!SetPayload(request->response_type(), request->response_size(),
+                      response->mutable_payload())) {
+        return Status(grpc::StatusCode::INTERNAL, "Error creating payload.");
+      }
+    }
+    return Status::OK;
+  }
+
+  Status StreamingOutputCall(
+      ServerContext* context, const StreamingOutputCallRequest* request,
+      ServerWriter<StreamingOutputCallResponse>* writer) {
+    StreamingOutputCallResponse response;
+    bool write_success = true;
+    response.mutable_payload()->set_type(request->response_type());
+    for (int i = 0; write_success && i < request->response_parameters_size();
+         i++) {
+      response.mutable_payload()->set_body(
+          grpc::string(request->response_parameters(i).size(), '\0'));
+      write_success = writer->Write(response);
+    }
+    if (write_success) {
+      return Status::OK;
+    } else {
+      return Status(grpc::StatusCode::INTERNAL, "Error writing response.");
+    }
+  }
+
+  Status StreamingInputCall(ServerContext* context,
+                            ServerReader<StreamingInputCallRequest>* reader,
+                            StreamingInputCallResponse* response) {
+    StreamingInputCallRequest request;
+    int aggregated_payload_size = 0;
+    while (reader->Read(&request)) {
+      if (request.has_payload() && request.payload().has_body()) {
+        aggregated_payload_size += request.payload().body().size();
+      }
+    }
+    response->set_aggregated_payload_size(aggregated_payload_size);
+    return Status::OK;
+  }
+
+  Status FullDuplexCall(
+      ServerContext* context,
+      ServerReaderWriter<StreamingOutputCallResponse,
+                         StreamingOutputCallRequest>* stream) {
+    StreamingOutputCallRequest request;
+    StreamingOutputCallResponse response;
+    bool write_success = true;
+    while (write_success && stream->Read(&request)) {
+      response.mutable_payload()->set_type(request.payload().type());
+      if (request.response_parameters_size() == 0) {
+        return Status(grpc::StatusCode::INTERNAL,
+                      "Request does not have response parameters.");
+      }
+      response.mutable_payload()->set_body(
+          grpc::string(request.response_parameters(0).size(), '\0'));
+      write_success = stream->Write(response);
+    }
+    if (write_success) {
+      return Status::OK;
+    } else {
+      return Status(grpc::StatusCode::INTERNAL, "Error writing response.");
+    }
+  }
+
+  Status HalfDuplexCall(
+      ServerContext* context,
+      ServerReaderWriter<StreamingOutputCallResponse,
+                         StreamingOutputCallRequest>* stream) {
+    std::vector<StreamingOutputCallRequest> requests;
+    StreamingOutputCallRequest request;
+    while (stream->Read(&request)) {
+      requests.push_back(request);
+    }
+
+    StreamingOutputCallResponse response;
+    bool write_success = true;
+    for (unsigned int i = 0; write_success && i < requests.size(); i++) {
+      response.mutable_payload()->set_type(requests[i].payload().type());
+      if (requests[i].response_parameters_size() == 0) {
+        return Status(grpc::StatusCode::INTERNAL,
+                      "Request does not have response parameters.");
+      }
+      response.mutable_payload()->set_body(
+          grpc::string(requests[i].response_parameters(0).size(), '\0'));
+      write_success = stream->Write(response);
+    }
+    if (write_success) {
+      return Status::OK;
+    } else {
+      return Status(grpc::StatusCode::INTERNAL, "Error writing response.");
+    }
+  }
+};
+
+void RunServer() {
+  std::ostringstream server_address;
+  server_address << "localhost:" << FLAGS_port;
+  TestServiceImpl service;
+
+  SimpleRequest request;
+  SimpleResponse response;
+
+  ServerBuilder builder;
+  builder.AddPort(server_address.str());
+  builder.RegisterService(service.service());
+  if (FLAGS_enable_ssl) {
+    SslServerCredentialsOptions ssl_opts = {
+        "",
+        {reinterpret_cast<const char*>(test_server1_key),
+         test_server1_key_size},
+        {reinterpret_cast<const char*>(test_server1_cert),
+         test_server1_cert_size}};
+    std::shared_ptr<ServerCredentials> creds =
+        ServerCredentialsFactory::SslCredentials(ssl_opts);
+    builder.SetCredentials(creds);
+  }
+  std::unique_ptr<Server> server(builder.BuildAndStart());
+  gpr_log(GPR_INFO, "Server listening on %s", server_address.str().c_str());
+  while (true) {
+    std::this_thread::sleep_for(std::chrono::seconds(5));
+  }
+}
+
+int main(int argc, char** argv) {
+  grpc_init();
+  google::ParseCommandLineFlags(&argc, &argv, true);
+
+  GPR_ASSERT(FLAGS_port != 0);
+  RunServer();
+
+  grpc_shutdown();
+  return 0;
+}
diff --git a/examples/tips/test.proto b/examples/tips/test.proto
new file mode 100644
index 0000000000..807a3fe677
--- /dev/null
+++ b/examples/tips/test.proto
@@ -0,0 +1,42 @@
+// An integration test service that covers all the method signature permutations
+// of unary/streaming requests/responses.
+syntax = "proto2";
+
+import "examples/tips/empty.proto";
+import "examples/tips/messages.proto";
+
+package grpc.testing;
+
+// A simple service to test the various types of RPCs and experiment with
+// performance with various types of payload.
+service TestService {
+  // One empty request followed by one empty response.
+  rpc EmptyCall(grpc.testing.Empty) returns (grpc.testing.Empty);
+
+  // One request followed by one response.
+  // The server returns the client payload as-is.
+  rpc UnaryCall(SimpleRequest) returns (SimpleResponse);
+
+  // One request followed by a sequence of responses (streamed download).
+  // The server returns the payload with client desired type and sizes.
+  rpc StreamingOutputCall(StreamingOutputCallRequest)
+      returns (stream StreamingOutputCallResponse);
+
+  // A sequence of requests followed by one response (streamed upload).
+  // The server returns the aggregated size of client payload as the result.
+  rpc StreamingInputCall(stream StreamingInputCallRequest)
+      returns (StreamingInputCallResponse);
+
+  // A sequence of requests with each request served by the server immediately.
+  // As one request could lead to multiple responses, this interface
+  // demonstrates the idea of full duplexing.
+  rpc FullDuplexCall(stream StreamingOutputCallRequest)
+      returns (stream StreamingOutputCallResponse);
+
+  // A sequence of requests followed by a sequence of responses.
+  // The server buffers all the client requests and then serves them in order. A
+  // stream of responses are returned to the client when the server starts with
+  // first request.
+  rpc HalfDuplexCall(stream StreamingOutputCallRequest)
+      returns (stream StreamingOutputCallResponse);
+}