通过OpenTelemetry上报Ruby应用数据

方法一：通过OpenTelemetry Ruby SDK手动埋点

1. 请先安装手动埋点所需的OpenTelemetry相关依赖：

gem install opentelemetry-api
gem install opentelemetry-sdk
gem install opentelemetry-exporter-otlp

2. 修改manual.rb文件中的endpoint、SERVICE_NAMESPACE、SERVICE_NAME、SERVICE_VERSION

3. 运行：ruby manual.rb

方法二：使用OpenTelemetry自动埋点

OpenTelemetry Ruby也可以自动在应用程序中埋点，实现自动观测。下面以基于Rails框架的Ruby Web应用为例，使用OpenTelemetry自动追踪链路并上报数据。

1. 下载开源Web应用框架 Rails： gem install rails

2. 使用Rails创建Web项目：rails new <your-project-name>

• 请将 <your-project-name> 替换为你的应用名，例如 rails new auto-demo

• 如果运行命令后出现 Rails is not currently installed on this system. 的报错，请关掉你的终端并重新打开，然后在新终端中重新输入命令。

3. 在 目录下的Gemfile中添加以下内容：

gem 'opentelemetry-sdk'
gem 'opentelemetry-exporter-otlp'
gem 'opentelemetry-instrumentation-all'

4. 下载此Web应用所需的第三方依赖：

• 进入项目根目录：cd <your-project-name>
• 下载Ruby依赖管理工具bundler：gem install bundler
• 执行命令，下载Gemfile中的依赖： bundle install

5. 在<your-project-name>/config/initializers目录下创建 opentelemetry.rb 文件，添加如下内容

• 请替换<endpoint>,<your-host-name>和<your-service-name>

# config/initializers/opentelemetry.rb
require 'opentelemetry/sdk'
require 'opentelemetry/exporter/otlp'
require 'opentelemetry/instrumentation/all'

OpenTelemetry::SDK.configure do |c|
  c.add_span_processor(
    OpenTelemetry::SDK::Trace::Export::BatchSpanProcessor.new(
      OpenTelemetry::Exporter::OTLP::Exporter.new(
        endpoint: '<endpoint>' # http方式接入
      )
    )
  )
  c.resource = OpenTelemetry::SDK::Resources::Resource.create({
    OpenTelemetry::SemanticConventions::Resource::HOST_NAME => '<your-host-name>', # 主机名
  })
  c.service_name = '<your-service-name>' # 服务名
  c.use_all() # 自动观测opentelemetry支持的所有库，
end

6. 运行项目：rails server

• 如果输出以下内容，则代表运行成功

* Puma version: 5.6.5 (ruby 2.7.2-p137) ("Birdie's Version")
*  Min threads: 5
*  Max threads: 5
*  Environment: development
*          PID: 79842
* Listening on http://127.0.0.1:3000
* Listening on http://[::1]:3000
Use Ctrl-C to stop

7. 在浏览器访问 http://127.0.0.1:3000，此时终端会输出以下内容。此时可登录链路追踪控制台查看Trace数据上报情况。

Started GET "/" for 127.0.0.1 at 2023-01-01 00:10:00 +0800
Processing by Rails::WelcomeController#index as HTML
  Rendering /Users/username/.rvm/gems/ruby-2.7.2/gems/railties-7.0.4.3/lib/rails/templates/rails/welcome/index.html.erb
  Rendered /Users/username/.rvm/gems/ruby-2.7.2/gems/railties-7.0.4.3/lib/rails/templates/rails/welcome/index.html.erb (Duration: 0.8ms | Allocations: 665)
Completed 200 OK in 6ms (Views: 2.1ms | ActiveRecord: 0.0ms | Allocations: 5440)