109 lines
3.1 KiB
Go
109 lines
3.1 KiB
Go
package backoff
|
|
|
|
import (
|
|
"math"
|
|
"testing"
|
|
"time"
|
|
)
|
|
|
|
func TestBackOff(t *testing.T) {
|
|
var (
|
|
testInitialInterval = 500 * time.Millisecond
|
|
testRandomizationFactor = 0.1
|
|
testMultiplier = 2.0
|
|
testMaxInterval = 5 * time.Second
|
|
testMaxElapsedTime = 15 * time.Minute
|
|
)
|
|
|
|
exp := NewExponentialBackOff()
|
|
exp.InitialInterval = testInitialInterval
|
|
exp.RandomizationFactor = testRandomizationFactor
|
|
exp.Multiplier = testMultiplier
|
|
exp.MaxInterval = testMaxInterval
|
|
exp.MaxElapsedTime = testMaxElapsedTime
|
|
exp.Reset()
|
|
|
|
var expectedResults = []time.Duration{500, 1000, 2000, 4000, 5000, 5000, 5000, 5000, 5000, 5000}
|
|
for i, d := range expectedResults {
|
|
expectedResults[i] = d * time.Millisecond
|
|
}
|
|
|
|
for _, expected := range expectedResults {
|
|
assertEquals(t, expected, exp.currentInterval)
|
|
// Assert that the next backoff falls in the expected range.
|
|
var minInterval = expected - time.Duration(testRandomizationFactor*float64(expected))
|
|
var maxInterval = expected + time.Duration(testRandomizationFactor*float64(expected))
|
|
var actualInterval = exp.NextBackOff()
|
|
if !(minInterval <= actualInterval && actualInterval <= maxInterval) {
|
|
t.Error("error")
|
|
}
|
|
}
|
|
}
|
|
|
|
func TestGetRandomizedInterval(t *testing.T) {
|
|
// 33% chance of being 1.
|
|
assertEquals(t, 1, getRandomValueFromInterval(0.5, 0, 2))
|
|
assertEquals(t, 1, getRandomValueFromInterval(0.5, 0.33, 2))
|
|
// 33% chance of being 2.
|
|
assertEquals(t, 2, getRandomValueFromInterval(0.5, 0.34, 2))
|
|
assertEquals(t, 2, getRandomValueFromInterval(0.5, 0.66, 2))
|
|
// 33% chance of being 3.
|
|
assertEquals(t, 3, getRandomValueFromInterval(0.5, 0.67, 2))
|
|
assertEquals(t, 3, getRandomValueFromInterval(0.5, 0.99, 2))
|
|
}
|
|
|
|
type TestClock struct {
|
|
i time.Duration
|
|
start time.Time
|
|
}
|
|
|
|
func (c *TestClock) Now() time.Time {
|
|
t := c.start.Add(c.i)
|
|
c.i += time.Second
|
|
return t
|
|
}
|
|
|
|
func TestGetElapsedTime(t *testing.T) {
|
|
var exp = NewExponentialBackOff()
|
|
exp.Clock = &TestClock{}
|
|
exp.Reset()
|
|
|
|
var elapsedTime = exp.GetElapsedTime()
|
|
if elapsedTime != time.Second {
|
|
t.Errorf("elapsedTime=%d", elapsedTime)
|
|
}
|
|
}
|
|
|
|
func TestMaxElapsedTime(t *testing.T) {
|
|
var exp = NewExponentialBackOff()
|
|
exp.Clock = &TestClock{start: time.Time{}.Add(10000 * time.Second)}
|
|
// Change the currentElapsedTime to be 0 ensuring that the elapsed time will be greater
|
|
// than the max elapsed time.
|
|
exp.startTime = time.Time{}
|
|
assertEquals(t, Stop, exp.NextBackOff())
|
|
}
|
|
|
|
func TestBackOffOverflow(t *testing.T) {
|
|
var (
|
|
testInitialInterval time.Duration = math.MaxInt64 / 2
|
|
testMaxInterval time.Duration = math.MaxInt64
|
|
testMultiplier = 2.1
|
|
)
|
|
|
|
exp := NewExponentialBackOff()
|
|
exp.InitialInterval = testInitialInterval
|
|
exp.Multiplier = testMultiplier
|
|
exp.MaxInterval = testMaxInterval
|
|
exp.Reset()
|
|
|
|
exp.NextBackOff()
|
|
// Assert that when an overflow is possible the current varerval time.Duration is set to the max varerval time.Duration .
|
|
assertEquals(t, testMaxInterval, exp.currentInterval)
|
|
}
|
|
|
|
func assertEquals(t *testing.T, expected, value time.Duration) {
|
|
if expected != value {
|
|
t.Errorf("got: %d, expected: %d", value, expected)
|
|
}
|
|
}
|