Factor out grpc_add_default_authority_if_not_present

17 files changed, 121 insertions, 24 deletions

diff --git a/BUILD b/BUILD
index a511896038..b56e6e4719 100644
--- a/BUILD
+++ b/BUILD
@@ -682,11 +682,11 @@ grpc_cc_library(
         "src/core/lib/channel/channel_stack_builder.cc",
         "src/core/lib/channel/channel_trace.cc",
         "src/core/lib/channel/channel_trace_registry.cc",
-        "src/core/lib/channel/status_util.cc",
         "src/core/lib/channel/connected_channel.cc",
         "src/core/lib/channel/handshaker.cc",
         "src/core/lib/channel/handshaker_factory.cc",
         "src/core/lib/channel/handshaker_registry.cc",
+        "src/core/lib/channel/status_util.cc",
         "src/core/lib/compression/compression.cc",
         "src/core/lib/compression/compression_internal.cc",
         "src/core/lib/compression/message_compress.cc",
@@ -829,12 +829,12 @@ grpc_cc_library(
         "src/core/lib/channel/channel_stack_builder.h",
         "src/core/lib/channel/channel_trace.h",
         "src/core/lib/channel/channel_trace_registry.h",
-        "src/core/lib/channel/status_util.h",
         "src/core/lib/channel/connected_channel.h",
         "src/core/lib/channel/context.h",
         "src/core/lib/channel/handshaker.h",
         "src/core/lib/channel/handshaker_factory.h",
         "src/core/lib/channel/handshaker_registry.h",
+        "src/core/lib/channel/status_util.h",
         "src/core/lib/compression/algorithm_metadata.h",
         "src/core/lib/compression/compression_internal.h",
         "src/core/lib/compression/message_compress.h",
@@ -1009,6 +1009,7 @@ grpc_cc_library(
 grpc_cc_library(
     name = "grpc_client_channel",
     srcs = [
+        "src/core/ext/filters/client_channel/authority.cc",
         "src/core/ext/filters/client_channel/backup_poller.cc",
         "src/core/ext/filters/client_channel/channel_connectivity.cc",
         "src/core/ext/filters/client_channel/client_channel.cc",
@@ -1032,6 +1033,7 @@ grpc_cc_library(
         "src/core/ext/filters/client_channel/uri_parser.cc",
     ],
     hdrs = [
+        "src/core/ext/filters/client_channel/authority.h",
         "src/core/ext/filters/client_channel/backup_poller.h",
         "src/core/ext/filters/client_channel/client_channel.h",
         "src/core/ext/filters/client_channel/client_channel_factory.h",
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9d4467beea..977cb64a14 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1093,6 +1093,7 @@ add_library(grpc
   src/core/ext/transport/chttp2/client/insecure/channel_create.cc
   src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc
   src/core/ext/transport/chttp2/client/chttp2_connector.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
@@ -1427,6 +1428,7 @@ add_library(grpc_cronet
   src/core/ext/filters/http/http_filters_plugin.cc
   src/core/ext/filters/http/message_compress/message_compress_filter.cc
   src/core/ext/filters/http/server/http_server_filter.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
@@ -1788,6 +1790,7 @@ add_library(grpc_test_util
   src/core/lib/transport/transport.cc
   src/core/lib/transport/transport_op_string.cc
   src/core/lib/debug/trace.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
@@ -2090,6 +2093,7 @@ add_library(grpc_test_util_unsecure
   src/core/lib/transport/transport.cc
   src/core/lib/transport/transport_op_string.cc
   src/core/lib/debug/trace.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
@@ -2405,6 +2409,7 @@ add_library(grpc_unsecure
   src/core/ext/transport/chttp2/client/insecure/channel_create.cc
   src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc
   src/core/ext/transport/chttp2/client/chttp2_connector.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
@@ -3194,6 +3199,7 @@ add_library(grpc++_cronet
   src/core/ext/filters/http/http_filters_plugin.cc
   src/core/ext/filters/http/message_compress/message_compress_filter.cc
   src/core/ext/filters/http/server/http_server_filter.cc
+  src/core/ext/filters/client_channel/authority.cc
   src/core/ext/filters/client_channel/backup_poller.cc
   src/core/ext/filters/client_channel/channel_connectivity.cc
   src/core/ext/filters/client_channel/client_channel.cc
diff --git a/Makefile b/Makefile
index 20992b6a65..e62c94b651 100644
--- a/Makefile
+++ b/Makefile
@@ -3419,6 +3419,7 @@ LIBGRPC_SRC = \
     src/core/ext/transport/chttp2/client/insecure/channel_create.cc \
     src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc \
     src/core/ext/transport/chttp2/client/chttp2_connector.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
@@ -3755,6 +3756,7 @@ LIBGRPC_CRONET_SRC = \
     src/core/ext/filters/http/http_filters_plugin.cc \
     src/core/ext/filters/http/message_compress/message_compress_filter.cc \
     src/core/ext/filters/http/server/http_server_filter.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
@@ -4117,6 +4119,7 @@ LIBGRPC_TEST_UTIL_SRC = \
     src/core/lib/transport/transport.cc \
     src/core/lib/transport/transport_op_string.cc \
     src/core/lib/debug/trace.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
@@ -4412,6 +4415,7 @@ LIBGRPC_TEST_UTIL_UNSECURE_SRC = \
     src/core/lib/transport/transport.cc \
     src/core/lib/transport/transport_op_string.cc \
     src/core/lib/debug/trace.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
@@ -4707,6 +4711,7 @@ LIBGRPC_UNSECURE_SRC = \
     src/core/ext/transport/chttp2/client/insecure/channel_create.cc \
     src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc \
     src/core/ext/transport/chttp2/client/chttp2_connector.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
@@ -5495,6 +5500,7 @@ LIBGRPC++_CRONET_SRC = \
     src/core/ext/filters/http/http_filters_plugin.cc \
     src/core/ext/filters/http/message_compress/message_compress_filter.cc \
     src/core/ext/filters/http/server/http_server_filter.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
diff --git a/build.yaml b/build.yaml
index b24eb854ae..46785a1a3f 100644
--- a/build.yaml
+++ b/build.yaml
@@ -544,6 +544,7 @@ filegroups:
   - grpc_base
 - name: grpc_client_channel
   headers:
+  - src/core/ext/filters/client_channel/authority.h
   - src/core/ext/filters/client_channel/backup_poller.h
   - src/core/ext/filters/client_channel/client_channel.h
   - src/core/ext/filters/client_channel/client_channel_factory.h
@@ -565,6 +566,7 @@ filegroups:
   - src/core/ext/filters/client_channel/subchannel_index.h
   - src/core/ext/filters/client_channel/uri_parser.h
   src:
+  - src/core/ext/filters/client_channel/authority.cc
   - src/core/ext/filters/client_channel/backup_poller.cc
   - src/core/ext/filters/client_channel/channel_connectivity.cc
   - src/core/ext/filters/client_channel/client_channel.cc
diff --git a/config.m4 b/config.m4
index a402e0f767..630fda6d68 100644
--- a/config.m4
+++ b/config.m4
@@ -321,6 +321,7 @@ if test "$PHP_GRPC" != "no"; then
     src/core/ext/transport/chttp2/client/insecure/channel_create.cc \
     src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc \
     src/core/ext/transport/chttp2/client/chttp2_connector.cc \
+    src/core/ext/filters/client_channel/authority.cc \
     src/core/ext/filters/client_channel/backup_poller.cc \
     src/core/ext/filters/client_channel/channel_connectivity.cc \
     src/core/ext/filters/client_channel/client_channel.cc \
diff --git a/config.w32 b/config.w32
index ba908b5e46..3623f2070e 100644
--- a/config.w32
+++ b/config.w32
@@ -298,6 +298,7 @@ if (PHP_GRPC != "no") {
     "src\\core\\ext\\transport\\chttp2\\client\\insecure\\channel_create.cc " +
     "src\\core\\ext\\transport\\chttp2\\client\\insecure\\channel_create_posix.cc " +
     "src\\core\\ext\\transport\\chttp2\\client\\chttp2_connector.cc " +
+    "src\\core\\ext\\filters\\client_channel\\authority.cc " +
     "src\\core\\ext\\filters\\client_channel\\backup_poller.cc " +
     "src\\core\\ext\\filters\\client_channel\\channel_connectivity.cc " +
     "src\\core\\ext\\filters\\client_channel\\client_channel.cc " +
diff --git a/gRPC-C++.podspec b/gRPC-C++.podspec
index 2501377127..403674d1ee 100644
--- a/gRPC-C++.podspec
+++ b/gRPC-C++.podspec
@@ -309,6 +309,7 @@ Pod::Spec.new do |s|
                       'src/core/tsi/transport_security_adapter.h',
                       'src/core/tsi/transport_security_interface.h',
                       'src/core/ext/transport/chttp2/client/chttp2_connector.h',
+                      'src/core/ext/filters/client_channel/authority.h',
                       'src/core/ext/filters/client_channel/backup_poller.h',
                       'src/core/ext/filters/client_channel/client_channel.h',
                       'src/core/ext/filters/client_channel/client_channel_factory.h',
diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index 137903249b..f9f9b77261 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -319,6 +319,7 @@ Pod::Spec.new do |s|
                       'src/core/tsi/transport_security_adapter.h',
                       'src/core/tsi/transport_security_interface.h',
                       'src/core/ext/transport/chttp2/client/chttp2_connector.h',
+                      'src/core/ext/filters/client_channel/authority.h',
                       'src/core/ext/filters/client_channel/backup_poller.h',
                       'src/core/ext/filters/client_channel/client_channel.h',
                       'src/core/ext/filters/client_channel/client_channel_factory.h',
@@ -738,6 +739,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/transport/chttp2/client/insecure/channel_create.cc',
                       'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc',
                       'src/core/ext/transport/chttp2/client/chttp2_connector.cc',
+                      'src/core/ext/filters/client_channel/authority.cc',
                       'src/core/ext/filters/client_channel/backup_poller.cc',
                       'src/core/ext/filters/client_channel/channel_connectivity.cc',
                       'src/core/ext/filters/client_channel/client_channel.cc',
@@ -897,6 +899,7 @@ Pod::Spec.new do |s|
                               'src/core/tsi/transport_security_adapter.h',
                               'src/core/tsi/transport_security_interface.h',
                               'src/core/ext/transport/chttp2/client/chttp2_connector.h',
+                              'src/core/ext/filters/client_channel/authority.h',
                               'src/core/ext/filters/client_channel/backup_poller.h',
                               'src/core/ext/filters/client_channel/client_channel.h',
                               'src/core/ext/filters/client_channel/client_channel_factory.h',
@@ -1380,6 +1383,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/filters/http/client/http_client_filter.h',
                       'src/core/ext/filters/http/message_compress/message_compress_filter.h',
                       'src/core/ext/filters/http/server/http_server_filter.h',
+                      'src/core/ext/filters/client_channel/authority.h',
                       'src/core/ext/filters/client_channel/backup_poller.h',
                       'src/core/ext/filters/client_channel/client_channel.h',
                       'src/core/ext/filters/client_channel/client_channel_factory.h',
@@ -1646,6 +1650,7 @@ Pod::Spec.new do |s|
                       'src/core/ext/filters/http/http_filters_plugin.cc',
                       'src/core/ext/filters/http/message_compress/message_compress_filter.cc',
                       'src/core/ext/filters/http/server/http_server_filter.cc',
+                      'src/core/ext/filters/client_channel/authority.cc',
                       'src/core/ext/filters/client_channel/backup_poller.cc',
                       'src/core/ext/filters/client_channel/channel_connectivity.cc',
                       'src/core/ext/filters/client_channel/client_channel.cc',
@@ -1930,6 +1935,7 @@ Pod::Spec.new do |s|
                               'src/core/ext/filters/http/client/http_client_filter.h',
                               'src/core/ext/filters/http/message_compress/message_compress_filter.h',
                               'src/core/ext/filters/http/server/http_server_filter.h',
+                              'src/core/ext/filters/client_channel/authority.h',
                               'src/core/ext/filters/client_channel/backup_poller.h',
                               'src/core/ext/filters/client_channel/client_channel.h',
                               'src/core/ext/filters/client_channel/client_channel_factory.h',
diff --git a/grpc.gemspec b/grpc.gemspec
index 1c0cfe35c5..dfb0fbb0ad 100644
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -250,6 +250,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/tsi/transport_security_adapter.h )
   s.files += %w( src/core/tsi/transport_security_interface.h )
   s.files += %w( src/core/ext/transport/chttp2/client/chttp2_connector.h )
+  s.files += %w( src/core/ext/filters/client_channel/authority.h )
   s.files += %w( src/core/ext/filters/client_channel/backup_poller.h )
   s.files += %w( src/core/ext/filters/client_channel/client_channel.h )
   s.files += %w( src/core/ext/filters/client_channel/client_channel_factory.h )
@@ -672,6 +673,7 @@ Gem::Specification.new do |s|
   s.files += %w( src/core/ext/transport/chttp2/client/insecure/channel_create.cc )
   s.files += %w( src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc )
   s.files += %w( src/core/ext/transport/chttp2/client/chttp2_connector.cc )
+  s.files += %w( src/core/ext/filters/client_channel/authority.cc )
   s.files += %w( src/core/ext/filters/client_channel/backup_poller.cc )
   s.files += %w( src/core/ext/filters/client_channel/channel_connectivity.cc )
   s.files += %w( src/core/ext/filters/client_channel/client_channel.cc )
diff --git a/grpc.gyp b/grpc.gyp
index 424641641e..7235e33849 100644
--- a/grpc.gyp
+++ b/grpc.gyp
@@ -474,6 +474,7 @@
         'src/core/ext/transport/chttp2/client/insecure/channel_create.cc',
         'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc',
         'src/core/ext/transport/chttp2/client/chttp2_connector.cc',
+        'src/core/ext/filters/client_channel/authority.cc',
         'src/core/ext/filters/client_channel/backup_poller.cc',
         'src/core/ext/filters/client_channel/channel_connectivity.cc',
         'src/core/ext/filters/client_channel/client_channel.cc',
@@ -730,6 +731,7 @@
         'src/core/lib/transport/transport.cc',
         'src/core/lib/transport/transport_op_string.cc',
         'src/core/lib/debug/trace.cc',
+        'src/core/ext/filters/client_channel/authority.cc',
         'src/core/ext/filters/client_channel/backup_poller.cc',
         'src/core/ext/filters/client_channel/channel_connectivity.cc',
         'src/core/ext/filters/client_channel/client_channel.cc',
@@ -960,6 +962,7 @@
         'src/core/lib/transport/transport.cc',
         'src/core/lib/transport/transport_op_string.cc',
         'src/core/lib/debug/trace.cc',
+        'src/core/ext/filters/client_channel/authority.cc',
         'src/core/ext/filters/client_channel/backup_poller.cc',
         'src/core/ext/filters/client_channel/channel_connectivity.cc',
         'src/core/ext/filters/client_channel/client_channel.cc',
@@ -1202,6 +1205,7 @@
         'src/core/ext/transport/chttp2/client/insecure/channel_create.cc',
         'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc',
         'src/core/ext/transport/chttp2/client/chttp2_connector.cc',
+        'src/core/ext/filters/client_channel/authority.cc',
         'src/core/ext/filters/client_channel/backup_poller.cc',
         'src/core/ext/filters/client_channel/channel_connectivity.cc',
         'src/core/ext/filters/client_channel/client_channel.cc',
diff --git a/package.xml b/package.xml
index a8e4667c86..5bb146db8a 100644
--- a/package.xml
+++ b/package.xml
@@ -257,6 +257,7 @@
     <file baseinstalldir="/" name="src/core/tsi/transport_security_adapter.h" role="src" />
     <file baseinstalldir="/" name="src/core/tsi/transport_security_interface.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/chttp2_connector.h" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/authority.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/backup_poller.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/client_channel.h" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/client_channel_factory.h" role="src" />
@@ -679,6 +680,7 @@
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/insecure/channel_create.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/transport/chttp2/client/chttp2_connector.cc" role="src" />
+    <file baseinstalldir="/" name="src/core/ext/filters/client_channel/authority.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/backup_poller.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/channel_connectivity.cc" role="src" />
     <file baseinstalldir="/" name="src/core/ext/filters/client_channel/client_channel.cc" role="src" />
diff --git a/src/core/ext/filters/client_channel/authority.cc b/src/core/ext/filters/client_channel/authority.cc
new file mode 100644
index 0000000000..46a9f39aed
--- /dev/null
+++ b/src/core/ext/filters/client_channel/authority.cc
@@ -0,0 +1,42 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#include <grpc/support/port_platform.h>
+
+#include "src/core/ext/filters/client_channel/authority.h"
+
+grpc_channel_args* grpc_add_default_authority_if_not_present(
+    const grpc_channel_args* args) {
+  const bool has_default_authority =
+      grpc_channel_args_find(args, GRPC_ARG_DEFAULT_AUTHORITY) != nullptr;
+  grpc_arg new_args[1];
+  size_t num_new_args = 0;
+  grpc_core::UniquePtr<char> default_authority;
+  if (!has_default_authority) {
+    const grpc_arg* server_uri_arg =
+        grpc_channel_args_find(args, GRPC_ARG_SERVER_URI);
+    const char* server_uri_str = grpc_channel_arg_get_string(server_uri_arg);
+    GPR_ASSERT(server_uri_str != nullptr);
+    default_authority =
+        grpc_core::ResolverRegistry::GetDefaultAuthority(server_uri_str);
+    GPR_ASSERT(default_authority != nullptr);
+    new_args[num_new_args++] = grpc_channel_arg_string_create(
+        const_cast<char*>(GRPC_ARG_DEFAULT_AUTHORITY), default_authority.get());
+  }
+  return grpc_channel_args_copy_and_add(args, new_args, num_new_args);
+}
diff --git a/src/core/ext/filters/client_channel/authority.h b/src/core/ext/filters/client_channel/authority.h
new file mode 100644
index 0000000000..0923e9d56c
--- /dev/null
+++ b/src/core/ext/filters/client_channel/authority.h
@@ -0,0 +1,36 @@
+/*
+ *
+ * Copyright 2018 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_AUTHORITY_H
+#define GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_AUTHORITY_H
+
+#include <grpc/support/port_platform.h>
+
+#include <grpc/grpc.h>
+
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/ext/filters/client_channel/resolver_registry.h"
+#include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/gprpp/memory.h"
+
+/// Returns a copy of \a args with the default authority channel arg set if it
+/// wasn't already present.
+grpc_channel_args* grpc_add_default_authority_if_not_present(
+    const grpc_channel_args* args);
+
+#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_AUTHORITY_H */
diff --git a/src/core/ext/transport/chttp2/client/insecure/channel_create.cc b/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
index 9fb87c2164..5b08b6cd36 100644
--- a/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
+++ b/src/core/ext/transport/chttp2/client/insecure/channel_create.cc
@@ -25,6 +25,7 @@
 #include <grpc/support/alloc.h>
 #include <grpc/support/string_util.h>
 
+#include "src/core/ext/filters/client_channel/authority.h"
 #include "src/core/ext/filters/client_channel/client_channel.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/ext/transport/chttp2/client/chttp2_connector.h"
@@ -38,33 +39,12 @@ static void client_channel_factory_ref(
 static void client_channel_factory_unref(
     grpc_client_channel_factory* cc_factory) {}
 
-static grpc_channel_args* add_default_authority_if_not_present(
-    const grpc_channel_args* args) {
-  const bool has_default_authority =
-      grpc_channel_args_find(args, GRPC_ARG_DEFAULT_AUTHORITY) != nullptr;
-  grpc_arg new_args[1];
-  size_t num_new_args = 0;
-  grpc_core::UniquePtr<char> default_authority;
-  if (!has_default_authority) {
-    const grpc_arg* server_uri_arg =
-        grpc_channel_args_find(args, GRPC_ARG_SERVER_URI);
-    const char* server_uri_str = grpc_channel_arg_get_string(server_uri_arg);
-    GPR_ASSERT(server_uri_str != nullptr);
-    default_authority =
-        grpc_core::ResolverRegistry::GetDefaultAuthority(server_uri_str);
-    GPR_ASSERT(default_authority != nullptr);
-    new_args[num_new_args++] = grpc_channel_arg_string_create(
-        const_cast<char*>(GRPC_ARG_DEFAULT_AUTHORITY), default_authority.get());
-  }
-  return grpc_channel_args_copy_and_add(args, new_args, num_new_args);
-}
-
 static grpc_subchannel* client_channel_factory_create_subchannel(
     grpc_client_channel_factory* cc_factory, const grpc_subchannel_args* args) {
   grpc_subchannel_args* final_sc_args =
       static_cast<grpc_subchannel_args*>(gpr_malloc(sizeof(*final_sc_args)));
   memcpy(final_sc_args, args, sizeof(*args));
-  final_sc_args->args = add_default_authority_if_not_present(args->args);
+  final_sc_args->args = grpc_add_default_authority_if_not_present(args->args);
   grpc_connector* connector = grpc_chttp2_connector_create();
   grpc_subchannel* s = grpc_subchannel_create(connector, final_sc_args);
   grpc_connector_unref(connector);
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index b3b114ef7c..2ec9e07e95 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -297,6 +297,7 @@ CORE_SOURCE_FILES = [
     'src/core/ext/transport/chttp2/client/insecure/channel_create.cc',
     'src/core/ext/transport/chttp2/client/insecure/channel_create_posix.cc',
     'src/core/ext/transport/chttp2/client/chttp2_connector.cc',
+    'src/core/ext/filters/client_channel/authority.cc',
     'src/core/ext/filters/client_channel/backup_poller.cc',
     'src/core/ext/filters/client_channel/channel_connectivity.cc',
     'src/core/ext/filters/client_channel/client_channel.cc',
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index 859efd29d1..92b97c4c82 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -866,6 +866,8 @@ src/core/README.md \
 src/core/ext/README.md \
 src/core/ext/census/grpc_context.cc \
 src/core/ext/filters/client_channel/README.md \
+src/core/ext/filters/client_channel/authority.cc \
+src/core/ext/filters/client_channel/authority.h \
 src/core/ext/filters/client_channel/backup_poller.cc \
 src/core/ext/filters/client_channel/backup_poller.h \
 src/core/ext/filters/client_channel/channel_connectivity.cc \
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 965487fbd6..b46a2b7f9a 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -9501,6 +9501,7 @@
       "grpc_deadline_filter"
     ], 
     "headers": [
+      "src/core/ext/filters/client_channel/authority.h", 
       "src/core/ext/filters/client_channel/backup_poller.h", 
       "src/core/ext/filters/client_channel/client_channel.h", 
       "src/core/ext/filters/client_channel/client_channel_factory.h", 
@@ -9526,6 +9527,8 @@
     "language": "c", 
     "name": "grpc_client_channel", 
     "src": [
+      "src/core/ext/filters/client_channel/authority.cc", 
+      "src/core/ext/filters/client_channel/authority.h", 
       "src/core/ext/filters/client_channel/backup_poller.cc", 
       "src/core/ext/filters/client_channel/backup_poller.h", 
       "src/core/ext/filters/client_channel/channel_connectivity.cc",