k8s.io/apiserver@v0.31.1/pkg/util/flowcontrol/fairqueuing/testing/eventclock/fake_event_clock_test.go (about)

     1  /*
     2  Copyright 2021 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package eventclock
    18  
    19  import (
    20  	"math/rand"
    21  	"sync/atomic"
    22  	"testing"
    23  	"time"
    24  
    25  	"k8s.io/apiserver/pkg/util/flowcontrol/fairqueuing/eventclock"
    26  )
    27  
    28  type TestableEventClock interface {
    29  	eventclock.Interface
    30  	SetTime(time.Time)
    31  	Run(*time.Time)
    32  }
    33  
    34  func exerciseTestableEventClock(t *testing.T, ec TestableEventClock, fuzz time.Duration) {
    35  	exerciseSettablePassiveClock(t, ec)
    36  	var numDone int32
    37  	now := ec.Now()
    38  	strictable := true
    39  	const batchSize = 100
    40  	times := make(chan time.Time, batchSize+1)
    41  	try := func(abs, strict bool, d time.Duration) {
    42  		f := func(u time.Time) {
    43  			realD := ec.Since(now)
    44  			atomic.AddInt32(&numDone, 1)
    45  			times <- u
    46  			if realD < d || strict && strictable && realD > d+fuzz {
    47  				t.Errorf("Asked for %v, got %v", d, realD)
    48  			}
    49  		}
    50  		if abs {
    51  			ec.EventAfterTime(f, now.Add(d))
    52  		} else {
    53  			ec.EventAfterDuration(f, d)
    54  		}
    55  	}
    56  	try(true, true, time.Minute)
    57  	for i := 0; i < batchSize; i++ {
    58  		d := time.Duration(rand.Intn(30)-3) * time.Second
    59  		try(i%2 == 0, d >= 0, d)
    60  	}
    61  	ec.Run(nil)
    62  	if numDone != batchSize+1 {
    63  		t.Errorf("Got only %v events", numDone)
    64  	}
    65  	lastTime := now.Add(-3 * time.Second)
    66  	for i := 0; i <= batchSize; i++ {
    67  		nextTime := <-times
    68  		if nextTime.Before(lastTime) {
    69  			t.Errorf("Got %s after %s", nextTime, lastTime)
    70  		}
    71  	}
    72  	endTime := ec.Now()
    73  	dx := endTime.Sub(now)
    74  	if dx > time.Minute+fuzz {
    75  		t.Errorf("Run started at %#+v, ended at %#+v, dx=%d", now, endTime, dx)
    76  	}
    77  	now = endTime
    78  	var shouldRun int32
    79  	strictable = false
    80  	for i := 0; i < batchSize; i++ {
    81  		d := time.Duration(rand.Intn(30)-3) * time.Second
    82  		try(i%2 == 0, d >= 0, d)
    83  		if d <= 12*time.Second {
    84  			shouldRun++
    85  		}
    86  	}
    87  	ec.SetTime(now.Add(13*time.Second - 1))
    88  	if numDone != batchSize+1+shouldRun {
    89  		t.Errorf("Expected %v, but %v ran", shouldRun, numDone-batchSize-1)
    90  	}
    91  	lastTime = now.Add(-3 * time.Second)
    92  	for i := int32(0); i < shouldRun; i++ {
    93  		nextTime := <-times
    94  		if nextTime.Before(lastTime) {
    95  			t.Errorf("Got %s after %s", nextTime, lastTime)
    96  		}
    97  		lastTime = nextTime
    98  	}
    99  }
   100  
   101  // copied from baseclocktest, because it is not public
   102  func exerciseSettablePassiveClock(t *testing.T, pc TestableEventClock) {
   103  	t1 := time.Now()
   104  	t2 := t1.Add(time.Hour)
   105  	pc.SetTime(t1)
   106  	tx := pc.Now()
   107  	if tx != t1 {
   108  		t.Errorf("SetTime(%#+v); Now() => %#+v", t1, tx)
   109  	}
   110  	dx := pc.Since(t1)
   111  	if dx != 0 {
   112  		t.Errorf("Since() => %v", dx)
   113  	}
   114  	pc.SetTime(t2)
   115  	dx = pc.Since(t1)
   116  	if dx != time.Hour {
   117  		t.Errorf("Since() => %v", dx)
   118  	}
   119  	tx = pc.Now()
   120  	if tx != t2 {
   121  		t.Errorf("Now() => %#+v", tx)
   122  	}
   123  }
   124  
   125  func TestFake(t *testing.T) {
   126  	startTime := time.Now()
   127  	fec, _ := NewFake(startTime, 0, nil)
   128  	exerciseTestableEventClock(t, fec, 0)
   129  	fec, _ = NewFake(startTime, time.Second, nil)
   130  	exerciseTestableEventClock(t, fec, time.Second)
   131  }