[GSM] Some initial structure (grpc#33952)

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src/cpp/ext/gsm/BUILD

@@ -0,0 +1,52 @@
+# gRPC Bazel BUILD file.
+#
+# Copyright 2023 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.
+
+load(
+    "//bazel:grpc_build_system.bzl",
+    "grpc_cc_library",
+)
+
+licenses(["reciprocal"])
+
+package(
+    default_visibility = ["//visibility:public"],
+    features = [
+        "layering_check",
+    ],
+)
+
+grpc_cc_library(
+    name = "gsm_observability",
+    srcs = [
+        "gsm_observability.cc",
+    ],
+    hdrs = [
+        "gsm_observability.h",
+    ],
+    external_deps = [
+        "absl/container:flat_hash_set",
+        "absl/status",
+        "absl/status:statusor",
+        "absl/strings",
+        "otel/sdk/src/metrics",
+    ],
+    language = "c++",
+    visibility = ["//:__subpackages__"],
+    deps = [
+        "//:gpr_platform",
+        "//src/cpp/ext/otel:otel_plugin",
+    ],
+)

src/cpp/ext/gsm/gsm_observability.cc

@@ -0,0 +1,59 @@
+//
+//
+// Copyright 2023 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/cpp/ext/gsm/gsm_observability.h"
+
+#include "absl/status/status.h"
+
+#include "src/cpp/ext/otel/otel_plugin.h"
+
+namespace grpc {
+namespace internal {
+
+//
+// GsmCustomObservabilityBuilder
+//
+
+GsmCustomObservabilityBuilder& GsmCustomObservabilityBuilder::SetMeterProvider(
+    std::shared_ptr<opentelemetry::sdk::metrics::MeterProvider>
+        meter_provider) {
+  builder_.SetMeterProvider(meter_provider);
+  return *this;
+}
+
+GsmCustomObservabilityBuilder& GsmCustomObservabilityBuilder::EnableMetrics(
+    const absl::flat_hash_set<absl::string_view>& metric_names) {
+  builder_.EnableMetrics(metric_names);
+  return *this;
+}
+
+GsmCustomObservabilityBuilder& GsmCustomObservabilityBuilder::DisableMetrics(
+    const absl::flat_hash_set<absl::string_view>& metric_names) {
+  builder_.DisableMetrics(metric_names);
+  return *this;
+}
+
+absl::StatusOr<GsmObservability>
+GsmCustomObservabilityBuilder::BuildAndRegister() {
+  return absl::UnimplementedError("Not Implemented");
+}
+
+}  // namespace internal
+}  // namespace grpc

src/cpp/ext/gsm/gsm_observability.h

@@ -0,0 +1,64 @@
+//
+//
+// Copyright 2023 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_SRC_CPP_EXT_GSM_GSM_OBSERVABILITY_H
+#define GRPC_SRC_CPP_EXT_GSM_GSM_OBSERVABILITY_H
+
+#include <grpc/support/port_platform.h>
+
+#include <memory>
+
+#include "absl/container/flat_hash_set.h"
+#include "absl/status/statusor.h"
+#include "absl/strings/string_view.h"
+#include "opentelemetry/sdk/metrics/meter_provider.h"
+
+#include "src/cpp/ext/otel/otel_plugin.h"
+
+namespace grpc {
+namespace internal {
+
+class GsmObservability {};
+
+class GsmCustomObservabilityBuilder {
+ public:
+  // TODO(yashykt): Should this take the SDK or the API MeterProvider? Benefit
+  // of SDK MeterProvider - Can explicitly set histogram bucket boundaries, but
+  // in the next iteration of the API, we would have it there as well.
+  GsmCustomObservabilityBuilder& SetMeterProvider(
+      std::shared_ptr<opentelemetry::sdk::metrics::MeterProvider>
+          meter_provider);
+  // Enable metrics in \a metric_names
+  GsmCustomObservabilityBuilder& EnableMetrics(
+      const absl::flat_hash_set<absl::string_view>& metric_names);
+  // Disable metrics in \a metric_names
+  GsmCustomObservabilityBuilder& DisableMetrics(
+      const absl::flat_hash_set<absl::string_view>& metric_names);
+  // Builds the GsmObservability plugin. The return status shows whether
+  // GsmObservability was successfully enabled or not. TODO(): Is the
+  // GsmObservability object useful?
+  absl::StatusOr<GsmObservability> BuildAndRegister();
+
+ private:
+  OpenTelemetryPluginBuilder builder_;
+};
+
+}  // namespace internal
+}  // namespace grpc
+
+#endif  // GRPC_SRC_CPP_EXT_GSM_GSM_OBSERVABILITY_H

test/cpp/ext/gsm/BUILD

@@ -0,0 +1,41 @@
+# Copyright 2023 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.
+
+load("//bazel:grpc_build_system.bzl", "grpc_cc_test", "grpc_package")
+
+licenses(["notice"])
+
+grpc_package(
+    name = "test/cpp/ext/gsm",
+    visibility = "tests",
+)
+
+grpc_cc_test(
+    name = "gsm_observability_test",
+    srcs = [
+        "gsm_observability_test.cc",
+    ],
+    external_deps = [
+        "gtest",
+        "otel/sdk/src/metrics",
+    ],
+    language = "C++",
+    tags = [
+    ],
+    deps = [
+        "//:grpc++",
+        "//src/cpp/ext/gsm:gsm_observability",
+        "//test/core/util:grpc_test_util",
+    ],
+)

test/cpp/ext/gsm/gsm_observability_test.cc

@@ -0,0 +1,43 @@
+//
+//
+// Copyright 2023 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 "src/cpp/ext/gsm/gsm_observability.h"
+
+#include "gtest/gtest.h"
+
+#include "test/core/util/test_config.h"
+
+namespace grpc {
+namespace testing {
+namespace {
+
+TEST(GsmCustomObservabilityBuilderTest, Basic) {
+  EXPECT_EQ(
+      internal::GsmCustomObservabilityBuilder().BuildAndRegister().status(),
+      absl::UnimplementedError("Not Implemented"));
+}
+
+}  // namespace
+}  // namespace testing
+}  // namespace grpc
+
+int main(int argc, char** argv) {
+  grpc::testing::TestEnvironment env(&argc, argv);
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}

tools/buildgen/extract_metadata_from_bazel_xml.py

@@ -738,7 +738,10 @@ def _exclude_unwanted_cc_tests(tests: List[str]) -> List[str]:
 
     # we have not added otel dependency outside of bazel
     tests = [
-        test for test in tests if not test.startswith("test/cpp/ext/otel:")
+        test
+        for test in tests
+        if not test.startswith("test/cpp/ext/otel:")
+        and not test.startswith("test/cpp/ext/gsm:")
     ]
 
     # missing opencensus/stats/stats.h

tools/distrib/fix_build_deps.py

@@ -100,7 +100,7 @@
     "opentelemetry/metrics/sync_instruments.h": "otel/api",
     "opentelemetry/nostd/shared_ptr.h": "otel/api",
     "opentelemetry/nostd/unique_ptr.h": "otel/api",
-    "sdk/include/opentelemetry/sdk/metrics/meter_provider.h": "otel/sdk/src/metrics",
+    "opentelemetry/sdk/metrics/meter_provider.h": "otel/sdk/src/metrics",
     "ares.h": "cares",
     "fuzztest/fuzztest.h": ["fuzztest", "fuzztest_main"],
     "google/api/monitored_resource.pb.h": (
@@ -379,6 +379,7 @@ def score_best(proposed, existing):
     "",
     "src/core",
     "src/cpp/ext/gcp",
+    "src/cpp/ext/gsm",
     "src/cpp/ext/otel",
     "test/core/backoff",
     "test/core/experiments",

tools/distrib/iwyu.sh

@@ -32,6 +32,7 @@ tools/distrib/gen_compilation_database.py \
   --dedup_targets \
   "//:*" \
   "//src/core/..." \
+  "//src/cpp/ext/gsm/..." \
   "//src/cpp/ext/otel/..." \
   "//src/compiler/..." \
   "//test/core/..." \