通过OpenTelemetry客户端埋点并上报C++应用数据_可观测链路 OpenTelemetry 版(OpenTelemetry)-阿里云帮助中心

通过OpenTelemetry为应用埋点并上报链路数据至可观测链路 OpenTelemetry 版后，可观测链路 OpenTelemetry 版即可开始监控应用，您可以查看应用拓扑、调用链路、异常事务、慢事务和SQL分析等一系列监控数据。本文介绍如何使用OpenTelemetry为C++应用埋点并上报数据。

前提条件

获取接入点信息

新版控制台

登录可观测链路 OpenTelemetry 版控制台，在左侧导航栏单击接入中心。
在开源框架区域单击OpenTelemetry卡片。
在弹出的OpenTelemetry面板中选择数据需要上报的地域。
说明
初次接入的地域将会自动进行资源初始化。
选择连接方式和上报方式，然后复制接入点信息。
- 连接方式：若您的服务部署在阿里云上，且所属地域与选择的接入地域一致，推荐使用阿里云内网方式，否则选择公网方式。
- 上报方式：根据客户端支持的协议类型选择HTTP或gRPC协议上报数据。

旧版控制台

登录可观测链路 OpenTelemetry 版控制台。
在左侧导航栏单击集群配置，然后在右侧页面单击接入点信息页签。
在页面顶部选择需要接入的地域，然后在集群信息区域打开显示Token开关。
在客户端采集工具区域单击OpenTelemetry。
在相关信息列中，获取接入点信息。
说明
如果应用部署于阿里云生产环境，则选择阿里云VPC网络接入点，否则选择公网接入点。

示例Demo

示例代码仓库地址：opentelemetry-cpp-demo

环境要求

C++版本 ≥ 11
请在Supported C++ Versions and Development Platforms中查看支持的C++版本和开发平台。

步骤一：环境准备

（可选）运行C++镜像。

docker pull gcc # 这个镜像用的系统是debian
docker run -it --name otel-cpp-demo gcc bash

安装必备的依赖。

protobuf
grpc

apt-get update
apt-get install sudo

sudo apt-get install git cmake g++ libcurl4-openssl-dev
# 安装 protobuf
sudo apt-get install protobuf-compiler libprotobuf-dev
# 安装 grpc
sudo apt-get install -y libgrpc++-dev libgrpc-dev protobuf-compiler-grpc

步骤二：安装OpenTelemetry C++ Library

git clone --recurse-submodules https://github.com/open-telemetry/opentelemetry-cpp

cd opentelemetry-cpp
mkdir build && cd build
cmake -DBUILD_TESTING=OFF -DWITH_OTLP_GRPC=ON -DWITH_OTLP_HTTP=ON ..

cmake --build . --target all

# 直接安装到/usr/local（推荐）
cmake --install . 

# 或者安装到指定路径
# cmake --install . --prefix /opentelemetry-cpp-lib

步骤三：在项目中使用OpenTelemetry C++ Library

通过HTTP上报数据

创建项目。

mkdir otel-http-export-demo
cd otel otel-http-export-demo

编写项目CMakeLists.txt文件。

cmake_minimum_required(VERSION 3.25.1) #version填cmake的版本，cmake --version
project(otel-http-export-demo) # 括号里填项目名

add_executable(otel-http-export-demo http_exporter.cc) # 项目名和main文件

find_package(opentelemetry-cpp CONFIG REQUIRED)
find_package(protobuf)
find_package(gRPC)
find_package(CURL)
find_package(nlohmann_json)

include_directories("${OPENTELEMETRY_CPP_INCLUDE_DIRS}")

target_link_libraries(
    opentelemetry_trace
    opentelemetry_common
    opentelemetry_http_client_curl
    opentelemetry_exporter_otlp_http
    opentelemetry_exporter_otlp_grpc
    opentelemetry_exporter_otlp_http_client
    opentelemetry_otlp_recordable
    opentelemetry_resources
)

编写Demo。

测试代码只包含一个http_exporter.cc文件。

请将${ServiceName}替换为您的应用名，将${HostName}替换为主机名。

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0

#include "opentelemetry/exporters/otlp/otlp_http_exporter_factory.h"
#include "opentelemetry/exporters/otlp/otlp_http_exporter_options.h"
#include "opentelemetry/context/propagation/global_propagator.h"
#include "opentelemetry/context/propagation/text_map_propagator.h"
#include "opentelemetry/exporters/ostream/span_exporter_factory.h"
#include "opentelemetry/nostd/shared_ptr.h"
#include "opentelemetry/sdk/trace/simple_processor_factory.h"
#include "opentelemetry/sdk/trace/tracer_context.h"
#include "opentelemetry/sdk/trace/tracer_context_factory.h"
#include "opentelemetry/sdk/trace/tracer_provider_factory.h"
#include "opentelemetry/trace/propagation/http_trace_context.h"
#include "opentelemetry/trace/provider.h"
#include "opentelemetry/ext/http/client/http_client_factory.h"
#include "opentelemetry/sdk/resource/semantic_conventions.h"
#include "opentelemetry/sdk/common/global_log_handler.h"

#include <string>


namespace trace     = opentelemetry::trace;
namespace trace_sdk = opentelemetry::sdk::trace;
namespace otlp      = opentelemetry::exporter::otlp;
namespace internal_log = opentelemetry::sdk::common::internal_log;
namespace resource = opentelemetry::sdk::resource;

namespace nostd = opentelemetry::nostd;

namespace
{
    opentelemetry::exporter::otlp::OtlpHttpExporterOptions opts;
    void InitTracer()
    {
        // 创建OTLP exporter
        auto exporter  = otlp::OtlpHttpExporterFactory::Create(opts);
        auto processor = trace_sdk::SimpleSpanProcessorFactory::Create(std::move(exporter));

        resource::ResourceAttributes attributes = {
                {resource::SemanticConventions::kServiceName, "${ServiceName}"}, // 应用名
                {resource::SemanticConventions::kHostName, "${HostName}"}
        };
        auto resource = opentelemetry::sdk::resource::Resource::Create(attributes);

        std::shared_ptr<opentelemetry::trace::TracerProvider> provider =
                trace_sdk::TracerProviderFactory::Create(std::move(processor), std::move(resource));

        // 设置Trace provider
        trace::Provider::SetTracerProvider(provider);
    }

    void CleanupTracer()
    {
        std::shared_ptr<opentelemetry::trace::TracerProvider> none;
        trace::Provider::SetTracerProvider(none);
    }

    nostd::shared_ptr<trace::Tracer> get_tracer()
    {
        auto provider = trace::Provider::GetTracerProvider();
        return provider->GetTracer("library name to trace", OPENTELEMETRY_SDK_VERSION);
    }

    void f1()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("f1"));
    }

    void f2()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("f2"));

        f1();
        f1();
    }

    void foo_library()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("library"));

        f2();
    }
}  // namespace

/*
  Usage:
  - example_otlp_http
  - example_otlp_http <URL>
  - example_otlp_http <URL> <DEBUG>
  - example_otlp_http <URL> <DEBUG> <BIN>
  <DEBUG> = yes|no, to turn console debug on or off
  <BIN> = bin, to export in binary format
*/
int main(int argc, char *argv[])
{
    if (argc > 1)
    {
        opts.url = argv[1];
        if (argc > 2)
        {
            std::string debug  = argv[2];
            opts.console_debug = debug != "" && debug != "0" && debug != "no";
        }

        if (argc > 3)
        {
            std::string binary_mode = argv[3];
            if (binary_mode.size() >= 3 && binary_mode.substr(0, 3) == "bin")
            {
                opts.content_type = otlp::HttpRequestContentType::kBinary;
            }
        }
    }

    if (opts.console_debug)
    {
        internal_log::GlobalLogHandler::SetLogLevel(internal_log::LogLevel::Debug);
    }

    InitTracer();

    foo_library();

    CleanupTracer();
}

编译项目。

mkdir build && cd build && cmake .. && make

运行项目。

./otel-http-export-demo ${http-endpoint}

请将${http-endpoint}替换为前提条件中获取的HTTP接入点信息。

例如：

./otel-http-export-demo http://tracing-analysis-dc-hz.aliyuncs.com/adapt_xxxxx_xxxxx/api/otlp/traces

通过gRPC上报数据

创建项目。

mkdir otel-grpc-export-demo
cd otel otel-grpc-export-demo

编写项目CMakeLists.txt文件。

cmake_minimum_required(VERSION 3.25.1) #version填cmake的版本，cmake --version
project(otel-grpc-export-demo) # 括号里填项目名

add_executable(otel-grpc-export-demo grpc_exporter.cc) # 项目名和main文件

find_package(opentelemetry-cpp CONFIG REQUIRED)
find_package(protobuf)
find_package(gRPC)
find_package(CURL)
find_package(nlohmann_json)

include_directories("${OPENTELEMETRY_CPP_INCLUDE_DIRS}")

target_link_libraries(
    otel-grpc-export-demo ${OPENTELEMETRY_CPP_LIBRARIES}
    opentelemetry_trace
    opentelemetry_common
    opentelemetry_http_client_curl
    opentelemetry_exporter_otlp_http
    opentelemetry_exporter_otlp_grpc
    opentelemetry_exporter_otlp_http_client
    opentelemetry_otlp_recordable
    opentelemetry_resources
)

编写Demo。

测试代码只包含一个grpc_exporter.cc文件。

请将${ServiceName}替换为您的应用名，将${HostName}替换为主机名。

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0

#include "opentelemetry/exporters/otlp/otlp_grpc_exporter_factory.h"
#include "opentelemetry/exporters/otlp/otlp_grpc_exporter_options.h"
#include "opentelemetry/context/propagation/global_propagator.h"
#include "opentelemetry/context/propagation/text_map_propagator.h"
#include "opentelemetry/exporters/ostream/span_exporter_factory.h"
#include "opentelemetry/nostd/shared_ptr.h"
#include "opentelemetry/sdk/trace/simple_processor_factory.h"
#include "opentelemetry/sdk/trace/tracer_context.h"
#include "opentelemetry/sdk/trace/tracer_context_factory.h"
#include "opentelemetry/sdk/trace/tracer_provider_factory.h"
#include "opentelemetry/trace/propagation/http_trace_context.h"
#include "opentelemetry/trace/provider.h"
#include "opentelemetry/ext/http/client/http_client_factory.h"
#include "opentelemetry/sdk/resource/semantic_conventions.h"
#include "opentelemetry/sdk/common/global_log_handler.h"

#include <string>


namespace trace     = opentelemetry::trace;
namespace trace_sdk = opentelemetry::sdk::trace;
namespace otlp      = opentelemetry::exporter::otlp;
namespace internal_log = opentelemetry::sdk::common::internal_log;
namespace resource = opentelemetry::sdk::resource;

namespace nostd = opentelemetry::nostd;

namespace
{
    opentelemetry::exporter::otlp::OtlpGrpcExporterOptions opts;
    void InitTracer()
    {
        // 创建OTLP exporter
        auto exporter  = otlp::OtlpGrpcExporterFactory::Create(opts);
        auto processor = trace_sdk::SimpleSpanProcessorFactory::Create(std::move(exporter));

        resource::ResourceAttributes attributes = {
                {resource::SemanticConventions::kServiceName, "${ServiceName} "}, // 应用名
                {resource::SemanticConventions::kHostName, "${HostName}"}
        };
        auto resource = opentelemetry::sdk::resource::Resource::Create(attributes);

        std::shared_ptr<opentelemetry::trace::TracerProvider> provider =
                trace_sdk::TracerProviderFactory::Create(std::move(processor), std::move(resource));

        // 设置Trace provider
        trace::Provider::SetTracerProvider(provider);
    }

    void CleanupTracer()
    {
        std::shared_ptr<opentelemetry::trace::TracerProvider> none;
        trace::Provider::SetTracerProvider(none);
    }

    nostd::shared_ptr<trace::Tracer> get_tracer()
    {
        auto provider = trace::Provider::GetTracerProvider();
        return provider->GetTracer("library name to trace", OPENTELEMETRY_SDK_VERSION);
    }

    void f1()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("f1"));
    }

    void f2()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("f2"));

        f1();
        f1();
    }

    void foo_library()
    {
        auto scoped_span = trace::Scope(get_tracer()->StartSpan("library"));

        f2();
    }
}  // namespace

/*
  Usage:
  - example_otlp_grpc
  - example_otlp_grpc <URL> <TOKEN>
*/
int main(int argc, char *argv[])
{
    if (argc > 1)
    {
        opts.endpoint = argv[1];
        if (argc > 2)
        {
            opts.metadata.insert(std::pair<std::string, std::string>("authentication",argv[2]));
        }

        if (argc > 3)
        {
            opts.use_ssl_credentials         = true;
            opts.ssl_credentials_cacert_path = argv[3];
        }
    }

    InitTracer();

    foo_library();

    CleanupTracer();
}

编译项目。

mkdir build && cd build && cmake .. && make

运行项目。

./otel-grpc-export-demo ${gRPC-endpoint} ${token}

请将${gRPC-endpoint}和${token}替换为前提条件中获取的gRPC接入点和鉴权Token。

例如：

./otel-grpc-export-demo http://tracing-analysis-dc-hz.aliyuncs.com:8090 xxxxx_xxxxxx

常见报错

运行后提示：

./otel-grpc-export-demo: error while loading shared libraries: libopentelemetry_proto_grpc.so: cannot open shared object file: No such file or directory

执行以下命令修改环境变量。

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib/

/usr/local/lib是opentelemetry-cpp安装的地址。

查看监控数据

在可观测链路 OpenTelemetry 版控制台的应用列表页面选择目标应用，查看链路数据。