feat(misc/retry): add execution retrier

misc/retry/retry.go

@@ -0,0 +1,39 @@
+package retry
+
+import (
+	"log"
+	"reflect"
+	"time"
+
+	"github.com/xoctopus/x/reflectx"
+)
+
+type Retry struct {
+	Repeats  int
+	Interval time.Duration
+}
+
+func (r *Retry) SetDefault() {
+	reflectx.Set(reflect.ValueOf(r), reflect.ValueOf(Default))
+}
+
+func (r Retry) Do(exec func() error) (err error) {
+	if r.Repeats <= 0 {
+		return exec()
+	}
+	for i := 0; i < r.Repeats; i++ {
+		if err = exec(); err != nil {
+			log.Printf("retry in %s [err: %v]", r.Interval, err)
+			time.Sleep(r.Interval)
+			continue
+		}
+		break
+	}
+	return
+}
+
+var Default = &Retry{3, 3 * time.Second}
+
+func Do(retry *Retry, exec func() error) error {
+	return retry.Do(exec)
+}

misc/retry/retry_test.go

@@ -0,0 +1,32 @@
+package retry_test
+
+import (
+	"testing"
+
+	g "github.com/onsi/gomega"
+	"github.com/pkg/errors"
+
+	"github.com/xoctopus/x/misc/retry"
+)
+
+func TestRetry_Do(t *testing.T) {
+	r := &retry.Retry{}
+	r.SetDefault()
+	g.NewWithT(t).Expect(r.Interval).To(g.Equal(retry.Default.Interval))
+	g.NewWithT(t).Expect(r.Repeats).To(g.Equal(retry.Default.Repeats))
+
+	times := 0
+	exec := func() error {
+		times++
+		if times == 3 {
+			return nil
+		}
+		return errors.Errorf("times %d", times)
+	}
+
+	g.NewWithT(t).Expect(retry.Do(r, exec)).To(g.BeNil())
+
+	times = 0
+	r.Repeats = 0
+	g.NewWithT(t).Expect(retry.Do(r, exec)).NotTo(g.BeNil())
+}