[xprof:oss] Added a gRPC utility for retrieving default credentials.

* Created a directory of Bazel build macros used by the profiler. [go/xprof-oss-self-contained, go/tfsl]
* profiler_client.cc
  * Removed redundant prefix "dns:///" which is already gRPC's default when not specified. Previously, it would prepend and result in a bad service address if URI had already been provided.
* Added log points for address binding and channel failures.

PiperOrigin-RevId: 327442840
Change-Id: Ia9e41bcbaff8d28267e0ca9ad8429151e51be3c4

tensorflow/core/profiler/builds/BUILD

@@ -0,0 +1,10 @@
+package(
+    default_visibility = ["//tensorflow/core/profiler:internal"],
+    licenses = ["notice"],  # Apache 2.0
+)
+
+# ONLY FOR DEV TESTING. DO NOT USE IF YOU DO NOT KNOW ABOUT IT ALREADY.
+config_setting(
+    name = "profiler_build_oss",
+    values = {"define": "profiler_build=oss"},
+)

tensorflow/core/profiler/builds/build_config.bzl

@@ -0,0 +1,14 @@
+"""Provides a redirection point for platform specific implementations of Starlark utilities."""
+
+load(
+    "//tensorflow/core/profiler/builds/oss:build_config.bzl",
+    _tf_profiler_alias = "tf_profiler_alias",
+)
+
+tf_profiler_alias = _tf_profiler_alias
+
+def if_profiler_oss(if_true, if_false = []):
+    return select({
+        "//tensorflow/core/profiler/builds:profiler_build_oss": if_true,
+        "//conditions:default": if_false,
+    })

tensorflow/core/profiler/builds/oss/BUILD

@@ -0,0 +1,8 @@
+# Tensorflow default + linux implementations of tensorflow/core/profiler libraries.
+
+package(
+    default_visibility = [
+        "//tensorflow/core/profiler:internal",
+    ],
+    licenses = ["notice"],  # Apache 2.0
+)

tensorflow/core/profiler/builds/oss/build_config.bzl

@@ -0,0 +1,7 @@
+# Platform-specific build configurations.
+"""
+TF profiler build macros for use in OSS.
+"""
+
+def tf_profiler_alias(target_dir, name):
+    return target_dir + "oss:" + name

tensorflow/core/profiler/rpc/BUILD

@@ -1,11 +1,31 @@
 load("//tensorflow:tensorflow.bzl", "tf_external_workspace_visible")  # buildifier: disable=same-origin-load
 load("//tensorflow:tensorflow.bzl", "tf_grpc_cc_dependency")  # buildifier: disable=same-origin-load
 load("//tensorflow:tensorflow.bzl", "tf_pybind_cc_library_wrapper")  # buildifier: disable=same-origin-load
+load("//tensorflow/core/profiler/builds:build_config.bzl", "tf_profiler_alias")
 
 package(
+    default_visibility = [
+        "//tensorflow/core/profiler:internal",
+    ],
     licenses = ["notice"],  # Apache 2.0
 )
 
+cc_library(
+    name = "grpc",
+    hdrs = ["grpc.h"],
+    deps = [
+        tf_profiler_alias("//tensorflow/core/profiler/rpc/", "grpc"),
+        tf_grpc_cc_dependency(),
+    ],
+)
+
+exports_files(
+    [
+        "grpc.h",
+    ],
+    visibility = ["//tensorflow/core/profiler/rpc:__subpackages__"],
+)
+
 cc_library(
     name = "profiler_service_impl",
     srcs = ["profiler_service_impl.cc"],
@@ -38,6 +58,7 @@ cc_library(
         "//tensorflow/python/profiler/internal:__pkg__",
     ],
     deps = [
+        ":grpc",
         ":profiler_service_impl",
         "//tensorflow/core:lib",
         "//tensorflow/core/profiler:profiler_service_proto_cc",

tensorflow/core/profiler/rpc/client/BUILD

@@ -56,6 +56,7 @@ cc_library(
         "//tensorflow/core:protos_all_cc",
         "//tensorflow/core/profiler:profiler_analysis_proto_cc",
         "//tensorflow/core/profiler:profiler_service_proto_cc",
+        "//tensorflow/core/profiler/rpc:grpc",
         tf_grpc_cc_dependency(),
     ],
     alwayslink = True,

tensorflow/core/profiler/rpc/client/profiler_client.cc

@@ -18,8 +18,10 @@ limitations under the License.
 
 #include "grpcpp/grpcpp.h"
 #include "tensorflow/core/platform/errors.h"
+#include "tensorflow/core/platform/logging.h"
 #include "tensorflow/core/platform/status.h"
 #include "tensorflow/core/platform/types.h"
+#include "tensorflow/core/profiler/rpc/grpc.h"
 #include "tensorflow/core/protobuf/error_codes.pb.h"
 
 namespace tensorflow {
@@ -36,9 +38,13 @@ template <typename T>
 std::unique_ptr<typename T::Stub> CreateStub(const std::string& service_addr) {
   ::grpc::ChannelArguments channel_args;
   channel_args.SetMaxReceiveMessageSize(std::numeric_limits<int32>::max());
-  return T::NewStub(::grpc::CreateCustomChannel(
-      "dns:///" + service_addr, ::grpc::InsecureChannelCredentials(),
-      channel_args));
+  // Default URI prefix is "dns:///" if not provided.
+  auto channel = ::grpc::CreateCustomChannel(
+      service_addr, ::grpc::InsecureChannelCredentials(), channel_args);
+  if (!channel) {
+    LOG(ERROR) << "Unable to create channel" << service_addr;
+  }
+  return T::NewStub(channel);
 }
 
 }  // namespace

tensorflow/core/profiler/rpc/grpc.h

@@ -0,0 +1,37 @@
+/* Copyright 2020 The TensorFlow Authors All Rights Reserved.
+
+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.
+==============================================================================*/
+// GRPC utilities
+
+#ifndef TENSORFLOW_CORE_PROFILER_COMMON_GRPC_GRPC_H_
+#define TENSORFLOW_CORE_PROFILER_COMMON_GRPC_GRPC_H_
+
+#include <memory>
+
+#include "grpcpp/security/credentials.h"
+#include "grpcpp/security/server_credentials.h"
+
+namespace tensorflow {
+namespace profiler {
+
+// Returns default credentials for use when creating a gRPC server.
+std::shared_ptr<::grpc::ServerCredentials> GetDefaultServerCredentials();
+
+// Returns default credentials for use when creating a gRPC channel.
+std::shared_ptr<::grpc::ChannelCredentials> GetDefaultChannelCredentials();
+
+}  // namespace profiler
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_CORE_PROFILER_COMMON_GRPC_GRPC_H_

tensorflow/core/profiler/rpc/oss/BUILD

@@ -0,0 +1,27 @@
+load("//tensorflow:tensorflow.bzl", "tf_grpc_cc_dependency")
+
+package(
+    default_visibility = [
+        "//tensorflow/core/profiler:internal",
+    ],
+    licenses = ["notice"],  # Apache 2.0
+)
+
+cc_library(
+    name = "grpc",
+    srcs = [
+        "grpc.cc",
+        "//tensorflow/core/profiler/rpc:grpc.h",
+    ],
+    deps = [
+        tf_grpc_cc_dependency(),
+    ],
+    alwayslink = True,
+)
+
+exports_files(
+    [
+        "grpc.cc",
+    ],
+    visibility = ["//tensorflow/core/profiler/rpc:__subpackages__"],
+)

tensorflow/core/profiler/rpc/oss/grpc.cc

@@ -0,0 +1,30 @@
+/* Copyright 2020 The TensorFlow Authors All Rights Reserved.
+
+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 "tensorflow/core/profiler/rpc/grpc.h"
+
+namespace tensorflow {
+namespace profiler {
+
+std::shared_ptr<::grpc::ServerCredentials> GetDefaultServerCredentials() {
+  return ::grpc::InsecureServerCredentials();
+}
+
+std::shared_ptr<::grpc::ChannelCredentials> GetDefaultChannelCredentials() {
+  return ::grpc::InsecureChannelCredentials();
+}
+
+}  // namespace profiler
+}  // namespace tensorflow

tensorflow/core/profiler/rpc/profiler_server.cc

@@ -23,18 +23,28 @@ limitations under the License.
 #include "tensorflow/core/platform/logging.h"
 #include "tensorflow/core/platform/types.h"
 #include "tensorflow/core/profiler/profiler_service.grpc.pb.h"
+#include "tensorflow/core/profiler/rpc/grpc.h"
 #include "tensorflow/core/profiler/rpc/profiler_service_impl.h"
 
 namespace tensorflow {
 
 void ProfilerServer::StartProfilerServer(int32 port) {
-  std::string server_address = absl::StrCat("0.0.0.0:", port);
+  std::string server_address = absl::StrCat("[::]:", port);
   service_ = CreateProfilerService();
   ::grpc::ServerBuilder builder;
-  builder.AddListeningPort(server_address, ::grpc::InsecureServerCredentials());
+
+  int selected_port = 0;
+  builder.AddListeningPort(
+      server_address, profiler::GetDefaultServerCredentials(), &selected_port);
   builder.RegisterService(service_.get());
   server_ = builder.BuildAndStart();
-  LOG(INFO) << "Profiling Server listening on " << server_address;
+  if (!selected_port) {
+    LOG(ERROR) << "Unable to bind to " << server_address << ":"
+               << selected_port;
+  } else {
+    LOG(INFO) << "Profiling Server listening on " << server_address << ":"
+              << selected_port;
+  }
 }
 
 ProfilerServer::~ProfilerServer() {