Meter provider sdk (open-telemetry#182)

sdk/include/opentelemetry/sdk/metrics/meter.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include "opentelemetry/metrics/meter.h"
+#include "opentelemetry/version.h"
+
+#include <memory>
+
+OPENTELEMETRY_BEGIN_NAMESPACE
+namespace sdk
+{
+namespace metrics
+{
+class Meter final : public opentelemetry::metrics::Meter, public std::enable_shared_from_this<Meter>
+{
+public:
+
+};
+}  // namespace trace
+}  // namespace sdk
+OPENTELEMETRY_END_NAMESPACE

sdk/include/opentelemetry/sdk/metrics/meter_provider.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#include "opentelemetry/nostd/shared_ptr.h"
+#include "opentelemetry/sdk/metrics/meter.h"
+#include "opentelemetry/metrics/meter_provider.h"
+
+#include <memory>
+
+OPENTELEMETRY_BEGIN_NAMESPACE
+namespace sdk
+{
+namespace metrics
+{
+class MeterProvider final : public opentelemetry::metrics::MeterProvider
+{
+public:
+  /**
+   * Initialize a new meter provider
+   */
+  explicit MeterProvider() noexcept;
+
+  opentelemetry::nostd::shared_ptr<opentelemetry::metrics::Meter> GetMeter(
+      nostd::string_view library_name,
+      nostd::string_view library_version = "") noexcept override;
+
+private:
+  std::shared_ptr<opentelemetry::metrics::Meter> meter_;
+};
+}  // namespace metrics
+}  // namespace sdk
+OPENTELEMETRY_END_NAMESPACE

sdk/src/CMakeLists.txt

@@ -1,2 +1,3 @@
 add_subdirectory(common)
 add_subdirectory(trace)
+add_subdirectory(metrics)

sdk/src/metrics/BUILD

@@ -0,0 +1,26 @@
+# Copyright 2020, OpenTelemetry 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.
+
+package(default_visibility = ["//visibility:public"])
+
+cc_library(
+    name = "metrics",
+    srcs = glob(["**/*.cc"]),
+    hdrs = glob(["**/*.h"]),
+    include_prefix = "src/metrics",
+    deps = [
+        "//api",
+        "//sdk:headers",
+    ],
+)

sdk/src/metrics/CMakeLists.txt

@@ -0,0 +1 @@
+add_library(opentelemetry_metrics meter_provider.cc)

sdk/src/metrics/meter_provider.cc

@@ -0,0 +1,21 @@
+#include "opentelemetry/sdk/metrics/meter_provider.h"
+
+OPENTELEMETRY_BEGIN_NAMESPACE
+namespace sdk
+{
+namespace metrics
+{
+MeterProvider::MeterProvider() noexcept
+    :  meter_(new Meter)
+{}
+
+opentelemetry::nostd::shared_ptr<opentelemetry::metrics::Meter> MeterProvider::GetMeter(
+    nostd::string_view library_name,
+    nostd::string_view library_version) noexcept
+{
+  return opentelemetry::nostd::shared_ptr<opentelemetry::metrics::Meter>(meter_);
+}
+
+}  // namespace metrics
+}  // namespace sdk
+OPENTELEMETRY_END_NAMESPACE

sdk/test/CMakeLists.txt

@@ -1,2 +1,3 @@
 add_subdirectory(common)
 add_subdirectory(trace)
+add_subdirectory(metrics)

sdk/test/metrics/BUILD

@@ -0,0 +1,10 @@
+cc_test(
+    name = "meter_provider_sdk_test",
+    srcs = [
+        "meter_provider_sdk_test.cc",
+    ],
+    deps = [
+        "//sdk/src/metrics",
+        "@com_google_googletest//:gtest_main",
+    ],
+)

sdk/test/metrics/CMakeLists.txt

@@ -0,0 +1,6 @@
+foreach(testname meter_provider_sdk_test)
+  add_executable(${testname} "${testname}.cc")
+  target_link_libraries(${testname} ${GTEST_BOTH_LIBRARIES}
+                        ${CMAKE_THREAD_LIBS_INIT} opentelemetry_common opentelemetry_metrics)
+  gtest_add_tests(TARGET ${testname} TEST_PREFIX metrics. TEST_LIST ${testname})
+endforeach()

sdk/test/metrics/meter_provider_sdk_test.cc

@@ -0,0 +1,22 @@
+#include "opentelemetry/sdk/metrics/meter_provider.h"
+#include "opentelemetry/sdk/metrics/meter.h"
+
+#include <gtest/gtest.h>
+
+using namespace opentelemetry::sdk::metrics;
+
+TEST(MeterProvider, GetMeter)
+{
+  MeterProvider tf;
+  auto t1 = tf.GetMeter("test");
+  auto t2 = tf.GetMeter("test");
+  auto t3 = tf.GetMeter("different", "1.0.0");
+  ASSERT_NE(nullptr, t1);
+  ASSERT_NE(nullptr, t2);
+  ASSERT_NE(nullptr, t3);
+
+  // Should return the same instance each time.
+  ASSERT_EQ(t1, t2);
+  ASSERT_EQ(t1, t3);
+
+}