集成SkyWalking实现调用链追踪

1. SkyWalking架构图

Receiver是SkyWalking的入口，支持gRPC和HTTP协议。
SkyWalking内部有分析和查询两个部分
存储方面SkyWalking支持Elasticsearch和MySql，H2等数据库

2. 代码集成SkyWalking

• 包引用：SkyAPM.Agent.AspNetCore/SkyAPM.Transport.Grpc/SkyAPM.Transport.Grpc.Protocol
• 应用程序根目录放置skyapm.json文件
• 程序环境变量中添加如下代码，

“ASPNETCORE_HOSTINGSTARTUPASSEMBLIES”: “SkyAPM.Agent.AspNetCore”

• 部署文件添加环境变量,服务地址

skywalking_hostingStartup=SkyAPM.Agent.AspNetCore
skywalking_servers=172.16.190.168:11800

• deployment.yaml中定义环境变量,读取上述环境标量的值

skyapm.json

{
  "SkyWalking": {
    "ServiceName": "ordering-api",
    "Namespace": "",
    "HeaderVersions": [
      "sw6"
    ],
    "Sampling": {
      "SamplePer3Secs": -1,
      "Percentage": -1.0
    },
    "Logging": {
      "Level": "Information",
      "FilePath": "logs\\skyapm-{Date}.log"
    },
    "Transport": {
      "Interval": 3000,
      "ProtocolVersion": "v6",
      "QueueSize": 30000,
      "BatchSize": 3000,
      "gRPC": {
        "Servers": "localhost:11800",
        "Timeout": 10000,
        "ConnectTimeout": 10000,
        "ReportTimeout": 600000
      }
    }
  }
}

默认情况下SkyWalking使用的是本地内存数据库,重启会丢失数据，线上环境建议使用Elasticsearch存储