如何在日志中注入traceID

2025-01-20

如何在日志中注入traceID

自动注入

如果我们使用 opentelemetry-go-auto-instrumentation 所支持的日志框架，如图所示。TraceId 和 SpanId 会自动注入日志。

package main

import (
  "go.uber.org/zap"
  "net/http"
)

func main() {
  http.HandleFunc("/log", func(w http.ResponseWriter, r *http.Request) {
    logger := zap.NewExample()
    logger.Debug("this is debug message")
    logger.Info("this is info message")
    logger.Warn("this is warn message")
    logger.Error("this is error message")
  })

  http.ListenAndServe(":9999", nil)
}

例如，如果我们用 opentelemetry-go-auto-instrumentation 生成下面的 Go 文件，运行二进制文件并访问 localhost:9999/log，就会看到下面的输出：

{"level":"debug","msg":"this is debug message","trace_id":"d62a8fea286cc66de9c68ca17d4faa88","span_id":"7cb6d692769ffd32"}
{"level":"info","msg":"this is info message","trace_id":"d62a8fea286cc66de9c68ca17d4faa88","span_id":"7cb6d692769ffd32"}
{"level":"warn","msg":"this is warn message","trace_id":"d62a8fea286cc66de9c68ca17d4faa88","span_id":"7cb6d692769ffd32"}
{"level":"error","msg":"this is error message","trace_id":"d62a8fea286cc66de9c68ca17d4faa88","span_id":"7cb6d692769ffd32"}
{"level":"debug","msg":"this is debug message","trace_id":"e56a6f1e7ed7af48cce8f64d045ed158","span_id":"def0b8cf10fe8844"}
{"level":"info","msg":"this is info message","trace_id":"e56a6f1e7ed7af48cce8f64d045ed158","span_id":"def0b8cf10fe8844"}
{"level":"warn","msg":"this is warn message","trace_id":"e56a6f1e7ed7af48cce8f64d045ed158","span_id":"def0b8cf10fe8844"}
{"level":"error","msg":"this is error message","trace_id":"e56a6f1e7ed7af48cce8f64d045ed158","span_id":"def0b8cf10fe8844"}

TraceId和SpanId会被自动注入到日志中。

手动注入

如果框架不支持 opentelemetry-go-auto-instrumentation。我们可以手动将 TraceId 和 SpanId 注入日志：

package main

import (
  "go.opentelemetry.io/otel/sdk/trace"
  "go.uber.org/zap"
  "net/http"
)

func main() {
  http.HandleFunc("/logwithtrace", func(w http.ResponseWriter, r *http.Request) {
    logger := zap.NewExample()
    traceId, spanId := trace.GetTraceAndSpanId()
    logger.Info("this is info message with fileds",
      zap.String("traceId", traceId),
      zap.String("spanId", spanId),
    )
  })
  http.ListenAndServe(":9999", nil)
}

例如，如果我们用 opentelemetry-go-auto-instrumentation 编译上面的 Go 文件，运行二进制文件，然后 curl localhost:9999/logwithtrace，就会看到下面的输出：

{"level":"info","msg":"this is info message with fileds","traceId":"92d63797010a2040484222a74c5ce304","spanId":"5a2c84c807a6e12c"}

上面的代码被放在示例目录中。