Golang 函数执行时间统计装饰器的一个实现详解

func f() {
 startTime := time.Now()
 logicStepOne()
 logicStepTwo()
 endTime := time.Now()
 timeDiff := timeDiff(startTime, endTime)
 log.Info("time diff: %s", timeDiff)
}

func doFWithTimeRecord() {
 startTime: = time.Now()
 f()
 endTime := Time.Now()
 timeDiff := timeDIff(startTime, endTime)
 log.Info("time diff: %s", timeDiff)
}

type SumFunc func(int64, int64) int64

func timedSumFunc(f SumFunc) SumFunc {
 return func(start, end int64) int64 {
  defer func(t time.Time) {
   fmt.Printf("--- Time Elapsed: %v ---\n", time.Since(t))
  }(time.Now())
  
  return f(start, end)
 }
}

type SumFunc func(int64, int64) int64

type TimeRecorder interface {
 SetCost(time.Duration)
 TimeCost() time.Duration
}

func TimeCostDecorator(rec TimeRecorder, f func()) func() {
 return func() {
  startTime := time.Now()
  f()
  endTime := time.Now()
  timeCost := endTime.Sub(startTime)
  rec.SetCost(timeCost)
 }
}

func NewTimeRecorder() TimeRecorder {
 return &timeRecorder{}
}

type timeRecorder struct {
 cost time.Duration
}

func (tr *timeRecorder) SetCost(cost time.Duration) {
 tr.cost = cost
}

func (tr *timeRecorder) Cost() time.Duration {
 return tr.cost
}

func TestTimeCostDecorator(t *testing.T) {
 testFunc := func() {
  time.Sleep(time.Duration(1) * time.Second)
 }
 
 type args struct {
  rec TimeRecorder
  f func()
 }
 
 tests := []struct {
  name string
  args args
 }{
  {
   "test time cost decorator",
   args{
    NewTimeRecorder(),
    testFunc,
   },
  },
 }
 for _, tt := range tests {
  t.Run(tt.name, func(t *testing.T) {
   got := TimeCostDecorator(tt.args.rec, tt.args.f)
   got()
   if tt.args.rec.Cost().Round(time.Second) != time.Duration(1) * time.Second.Round(time.Second) {
    "Record time cost abnormal, recorded cost: %s, real cost: %s",
    tt.args.rec.Cost().String(),
    tt.Duration(1) * time.Second,
   }
  }) 
 }
}