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|
package retrier
import (
"testing"
"time"
)
var i int
func genWork(returns []error) func() error {
i = 0
return func() error {
i++
if i > len(returns) {
return nil
}
return returns[i-1]
}
}
func TestRetrier(t *testing.T) {
r := New([]time.Duration{0, 10 * time.Millisecond}, WhitelistClassifier{errFoo})
err := r.Run(genWork([]error{errFoo, errFoo}))
if err != nil {
t.Error(err)
}
if i != 3 {
t.Error("run wrong number of times")
}
err = r.Run(genWork([]error{errFoo, errBar}))
if err != errBar {
t.Error(err)
}
if i != 2 {
t.Error("run wrong number of times")
}
err = r.Run(genWork([]error{errBar, errBaz}))
if err != errBar {
t.Error(err)
}
if i != 1 {
t.Error("run wrong number of times")
}
}
func TestRetrierNone(t *testing.T) {
r := New(nil, nil)
i = 0
err := r.Run(func() error {
i++
return errFoo
})
if err != errFoo {
t.Error(err)
}
if i != 1 {
t.Error("run wrong number of times")
}
i = 0
err = r.Run(func() error {
i++
return nil
})
if err != nil {
t.Error(err)
}
if i != 1 {
t.Error("run wrong number of times")
}
}
func TestRetrierJitter(t *testing.T) {
r := New([]time.Duration{0, 10 * time.Millisecond, 4 * time.Hour}, nil)
if r.calcSleep(0) != 0 {
t.Error("Incorrect sleep calculated")
}
if r.calcSleep(1) != 10*time.Millisecond {
t.Error("Incorrect sleep calculated")
}
if r.calcSleep(2) != 4*time.Hour {
t.Error("Incorrect sleep calculated")
}
r.SetJitter(0.25)
for i := 0; i < 20; i++ {
if r.calcSleep(0) != 0 {
t.Error("Incorrect sleep calculated")
}
slp := r.calcSleep(1)
if slp < 7500*time.Microsecond || slp > 12500*time.Microsecond {
t.Error("Incorrect sleep calculated")
}
slp = r.calcSleep(2)
if slp < 3*time.Hour || slp > 5*time.Hour {
t.Error("Incorrect sleep calculated")
}
}
r.SetJitter(-1)
if r.jitter != 0.25 {
t.Error("Invalid jitter value accepted")
}
r.SetJitter(2)
if r.jitter != 0.25 {
t.Error("Invalid jitter value accepted")
}
}
func ExampleRetrier() {
r := New(ConstantBackoff(3, 100*time.Millisecond), nil)
err := r.Run(func() error {
// do some work
return nil
})
if err != nil {
// handle the case where the work failed three times
}
}
|
