hwlogutils.go

//  Copyright(C) 2021. Huawei Technologies Co.,Ltd.  All rights reserved.

// Package hwlog provides the capability of processing Huawei log rules.
package hwlog

import (
   "bytes"
   "context"
   "fmt"
   "go.uber.org/zap"
   "runtime"
   "strings"
)

// printHelper helper function for log printing
func printHelper(f func(string, ...zap.Field), msg string, ctx ...context.Context) {
   str := getCallerInfo(ctx...)
   f(str + msg)
}

// getCallerInfo gets the caller's information
func getCallerInfo(ctx ...context.Context) string {
   var deep = stackDeep
   var userID interface{}
   var traceID interface{}
   for _, c := range ctx {
      if c == nil {
         deep++
         continue
      }
      userID = c.Value(UserID)
      traceID = c.Value(ReqID)
   }
   var funcName string
   pc, codePath, codeLine, ok := runtime.Caller(deep)
   if ok {
      funcName = runtime.FuncForPC(pc).Name()
   }
   p := strings.Split(codePath, "/")
   l := len(p)
   if l == pathLen {
      funcName = p[l-1]
   } else if l > pathLen {
      funcName = fmt.Sprintf("%s/%s", p[l-pathLen], p[l-1])
   }
   callerPath := fmt.Sprintf("%s:%d", funcName, codeLine)
   goroutineID := getGoroutineID()
   str := fmt.Sprintf("%-8s%s    ", goroutineID, callerPath)
   if userID != nil || traceID != nil {
      str = fmt.Sprintf("%s{%v}-{%v} ", str, userID, traceID)
   }
   return str
}

// getCallerGoroutineID gets the goroutineID
func getGoroutineID() string {
   b := make([]byte, bitsize, bitsize)
   b = b[:runtime.Stack(b, false)]
   b = bytes.TrimPrefix(b, []byte("goroutine "))
   b = b[:bytes.IndexByte(b, ' ')]
   return string(b)
}