modify stress_test command line options

Modify command line options to be consistent with interop_client.
diff --git a/Makefile b/Makefile
index 38be9e6..b0b527d 100644
--- a/Makefile
+++ b/Makefile
@@ -13077,6 +13077,7 @@
     $(GENDIR)/src/proto/grpc/testing/messages.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.grpc.pb.cc \
     $(GENDIR)/src/proto/grpc/testing/metrics.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.grpc.pb.cc \
     $(GENDIR)/src/proto/grpc/testing/test.pb.cc $(GENDIR)/src/proto/grpc/testing/test.grpc.pb.cc \
+    test/cpp/interop/client_helper.cc \
     test/cpp/interop/interop_client.cc \
     test/cpp/interop/stress_interop_client.cc \
     test/cpp/interop/stress_test.cc \
@@ -13119,6 +13120,8 @@
 
 $(OBJDIR)/$(CONFIG)/src/proto/grpc/testing/test.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
 
+$(OBJDIR)/$(CONFIG)/test/cpp/interop/client_helper.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
+
 $(OBJDIR)/$(CONFIG)/test/cpp/interop/interop_client.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
 
 $(OBJDIR)/$(CONFIG)/test/cpp/interop/stress_interop_client.o:  $(LIBDIR)/$(CONFIG)/libgrpc++_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc_test_util.a $(LIBDIR)/$(CONFIG)/libgrpc++.a $(LIBDIR)/$(CONFIG)/libgrpc.a $(LIBDIR)/$(CONFIG)/libgpr_test_util.a $(LIBDIR)/$(CONFIG)/libgpr.a $(LIBDIR)/$(CONFIG)/libgrpc++_test_config.a
@@ -13134,6 +13137,7 @@
 -include $(STRESS_TEST_OBJS:.o=.dep)
 endif
 endif
+$(OBJDIR)/$(CONFIG)/test/cpp/interop/client_helper.o: $(GENDIR)/src/proto/grpc/testing/empty.pb.cc $(GENDIR)/src/proto/grpc/testing/empty.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/test.pb.cc $(GENDIR)/src/proto/grpc/testing/test.grpc.pb.cc
 $(OBJDIR)/$(CONFIG)/test/cpp/interop/interop_client.o: $(GENDIR)/src/proto/grpc/testing/empty.pb.cc $(GENDIR)/src/proto/grpc/testing/empty.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/test.pb.cc $(GENDIR)/src/proto/grpc/testing/test.grpc.pb.cc
 $(OBJDIR)/$(CONFIG)/test/cpp/interop/stress_interop_client.o: $(GENDIR)/src/proto/grpc/testing/empty.pb.cc $(GENDIR)/src/proto/grpc/testing/empty.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/test.pb.cc $(GENDIR)/src/proto/grpc/testing/test.grpc.pb.cc
 $(OBJDIR)/$(CONFIG)/test/cpp/interop/stress_test.o: $(GENDIR)/src/proto/grpc/testing/empty.pb.cc $(GENDIR)/src/proto/grpc/testing/empty.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.pb.cc $(GENDIR)/src/proto/grpc/testing/messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.pb.cc $(GENDIR)/src/proto/grpc/testing/metrics.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/test.pb.cc $(GENDIR)/src/proto/grpc/testing/test.grpc.pb.cc
diff --git a/build.yaml b/build.yaml
index 2a06653..85485f6 100644
--- a/build.yaml
+++ b/build.yaml
@@ -3351,6 +3351,7 @@
   - src/proto/grpc/testing/messages.proto
   - src/proto/grpc/testing/metrics.proto
   - src/proto/grpc/testing/test.proto
+  - test/cpp/interop/client_helper.cc
   - test/cpp/interop/interop_client.cc
   - test/cpp/interop/stress_interop_client.cc
   - test/cpp/interop/stress_test.cc
diff --git a/test/cpp/interop/stress_test.cc b/test/cpp/interop/stress_test.cc
index 5647cb5..dac8015 100644
--- a/test/cpp/interop/stress_test.cc
+++ b/test/cpp/interop/stress_test.cc
@@ -46,6 +46,7 @@
 
 #include "src/proto/grpc/testing/metrics.grpc.pb.h"
 #include "src/proto/grpc/testing/metrics.pb.h"
+#include "test/cpp/interop/client_helper.h"
 #include "test/cpp/interop/interop_client.h"
 #include "test/cpp/interop/stress_interop_client.h"
 #include "test/cpp/util/metrics_server.h"
@@ -68,7 +69,8 @@
 
 DEFINE_string(server_addresses, "localhost:8080",
               "The list of server"
-              " addresses in the format:\n"
+              "addresses. This option is ignored if either\n"
+              "server_port or server_host is specified. The format is: \n"
               " \"<name_1>:<port_1>,<name_2>:<port_1>...<name_N>:<port_N>\"\n"
               " Note: <name> can be servername or IP address.");
 
@@ -79,6 +81,34 @@
              "indicates the max number of parallel RPC calls on each channel "
              "at any given time.");
 
+DEFINE_string(test_case, "",
+              "Configure different test cases. Valid options are:\n\n"
+              "all : all test cases;\n"
+              "cancel_after_begin : cancel stream after starting it;\n"
+              "cancel_after_first_response: cancel on first response;\n"
+              "client_compressed_streaming : compressed request streaming with "
+              "client_compressed_unary : single compressed request;\n"
+              "client_streaming : request streaming with single response;\n"
+              "compute_engine_creds: large_unary with compute engine auth;\n"
+              "custom_metadata: server will echo custom metadata;\n"
+              "empty_stream : bi-di stream with no request/response;\n"
+              "empty_unary : empty (zero bytes) request and response;\n"
+              "half_duplex : half-duplex streaming;\n"
+              "jwt_token_creds: large_unary with JWT token auth;\n"
+              "large_unary : single request and (large) response;\n"
+              "oauth2_auth_token: raw oauth2 access token auth;\n"
+              "per_rpc_creds: raw oauth2 access token on a single rpc;\n"
+              "ping_pong : full-duplex streaming;\n"
+              "response streaming;\n"
+              "server_compressed_streaming : single request with compressed "
+              "server_compressed_unary : single compressed response;\n"
+              "server_streaming : single request with response streaming;\n"
+              "slow_consumer : single request with response streaming with "
+              "slow client consumer;\n"
+              "status_code_and_message: verify status code & message;\n"
+              "timeout_on_sleeping_server: deadline exceeds on stream;\n"
+              "unimplemented_method: client calls an unimplemented_method;\n");
+
 // TODO(sreek): Add more test cases here in future
 DEFINE_string(test_cases, "",
               "List of test cases to call along with the"
@@ -115,6 +145,17 @@
             "If set to 'true', abort() is not called in case of transient "
             "failures like temporary connection failures.");
 
+// Options from client.cc (for compatibility with interop test).
+// TODO(sreek): Consolidate overlapping options
+DEFINE_bool(use_tls, false, "Whether to use tls.");
+DEFINE_bool(use_test_ca, false, "False to use SSL roots for google");
+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.fr",
+              "Override the server host which is sent in HTTP header");
+DEFINE_string(service_account_key_file, "",
+              "Path to service account json key file.");
+
 using grpc::testing::kTestCaseList;
 using grpc::testing::MetricsService;
 using grpc::testing::MetricsServiceImpl;
@@ -200,6 +241,8 @@
 void LogParameterInfo(const std::vector<grpc::string>& addresses,
                       const std::vector<std::pair<TestCaseType, int>>& tests) {
   gpr_log(GPR_INFO, "server_addresses: %s", FLAGS_server_addresses.c_str());
+  gpr_log(GPR_INFO, "server_host: %s", FLAGS_server_host.c_str());
+  gpr_log(GPR_INFO, "server_port: %d", FLAGS_server_port);
   gpr_log(GPR_INFO, "test_cases : %s", FLAGS_test_cases.c_str());
   gpr_log(GPR_INFO, "sleep_duration_ms: %d", FLAGS_sleep_duration_ms);
   gpr_log(GPR_INFO, "test_duration_secs: %d", FLAGS_test_duration_secs);
@@ -243,11 +286,24 @@
 
   // Parse the server addresses
   std::vector<grpc::string> server_addresses;
-  ParseCommaDelimitedString(FLAGS_server_addresses, server_addresses);
+  if (FLAGS_server_port != 0) {
+    // We are using interop_client style cmdline options.
+    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::string host_port_str(host_port);
+    ParseCommaDelimitedString(host_port_str, server_addresses);
+  } else {
+    ParseCommaDelimitedString(FLAGS_server_addresses, server_addresses);
+  }
 
   // Parse test cases and weights
   if (FLAGS_test_cases.length() == 0) {
-    gpr_log(GPR_ERROR, "Not running tests. The 'test_cases' string is empty");
+    // We are using interop_client style test_case option
+    FLAGS_test_cases = FLAGS_test_case + ":100";
+  } else if (FLAGS_test_case != "") {
+    gpr_log(GPR_ERROR, "specify --test_case or --test_cases but not both.");
     return 1;
   }
 
@@ -283,9 +339,13 @@
     // Create channel(s) for each server
     for (int channel_idx = 0; channel_idx < FLAGS_num_channels_per_server;
          channel_idx++) {
-      // TODO (sreek). This won't work for tests that require Authentication
-      std::shared_ptr<grpc::Channel> channel(
-          grpc::CreateChannel(*it, grpc::InsecureChannelCredentials()));
+      gpr_log(GPR_INFO, "Starting test with %s channel_idx=%d..", it->c_str(), channel_idx);
+      std::shared_ptr<grpc::Channel> channel;
+      if (FLAGS_use_tls) {
+        channel = grpc::testing::CreateChannelForTestCase(FLAGS_test_case);
+      } else {
+        channel = grpc::CreateChannel(*it, grpc::InsecureChannelCredentials());
+      }
 
       // Create stub(s) for each channel
       for (int stub_idx = 0; stub_idx < FLAGS_num_stubs_per_channel;
@@ -311,8 +371,11 @@
   }
 
   // Start metrics server before waiting for the stress test threads
-  std::unique_ptr<grpc::Server> metrics_server =
-      metrics_service.StartServer(FLAGS_metrics_port);
+  if (FLAGS_metrics_port > 0) {
+    std::unique_ptr<grpc::Server> metrics_server =
+        metrics_service.StartServer(FLAGS_metrics_port);
+  }
+
 
   // Wait for the stress test threads to complete
   for (auto it = test_threads.begin(); it != test_threads.end(); it++) {
diff --git a/tools/run_tests/sources_and_headers.json b/tools/run_tests/sources_and_headers.json
index 7cfb1d4..aa5789b 100644
--- a/tools/run_tests/sources_and_headers.json
+++ b/tools/run_tests/sources_and_headers.json
@@ -3135,6 +3135,7 @@
     "language": "c++", 
     "name": "stress_test", 
     "src": [
+      "test/cpp/interop/client_helper.cc", 
       "test/cpp/interop/client_helper.h", 
       "test/cpp/interop/interop_client.cc", 
       "test/cpp/interop/interop_client.h", 
diff --git a/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj b/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj
index ba2ed46..8e1b6bb 100644
--- a/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj
+++ b/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj
@@ -198,6 +198,8 @@
     </ClCompile>
     <ClInclude Include="$(SolutionDir)\..\src\proto\grpc\testing\test.grpc.pb.h">
     </ClInclude>
+    <ClCompile Include="$(SolutionDir)\..\test\cpp\interop\client_helper.cc">
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\test\cpp\interop\interop_client.cc">
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\test\cpp\interop\stress_interop_client.cc">
diff --git a/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj.filters b/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj.filters
index 08367b7..476c04e 100644
--- a/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj.filters
+++ b/vsprojects/vcxproj/test/stress_test/stress_test.vcxproj.filters
@@ -13,6 +13,9 @@
     <ClCompile Include="$(SolutionDir)\..\src\proto\grpc\testing\test.proto">
       <Filter>src\proto\grpc\testing</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\test\cpp\interop\client_helper.cc">
+      <Filter>test\cpp\interop</Filter>
+    </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\test\cpp\interop\interop_client.cc">
       <Filter>test\cpp\interop</Filter>
     </ClCompile>