Add new retry (#5911)

* Add new retry

Signed-off-by: godchen <qingxiang.chen@zilliz.com>

* fix gofmt

Signed-off-by: godchen <qingxiang.chen@zilliz.com>

internal/util/new_retry/options.go

@@ -0,0 +1,48 @@
+// Copyright (C) 2019-2020 Zilliz. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software distributed under the License
+// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+// or implied. See the License for the specific language governing permissions and limitations under the License.
+
+package retry
+
+import "time"
+
+type Config struct {
+	attempts     uint
+	sleep        time.Duration
+	maxSleepTime time.Duration
+}
+
+func NewDefaultConfig() *Config {
+	return &Config{
+		attempts:     uint(10),
+		sleep:        200 * time.Millisecond,
+		maxSleepTime: 1 * time.Second,
+	}
+}
+
+type Option func(*Config)
+
+func Attempts(attempts uint) Option {
+	return func(c *Config) {
+		c.attempts = attempts
+	}
+}
+
+func Sleep(sleep time.Duration) Option {
+	return func(c *Config) {
+		c.sleep = sleep
+	}
+}
+
+func MaxSleepTime(maxSleepTime time.Duration) Option {
+	return func(c *Config) {
+		c.maxSleepTime = maxSleepTime
+	}
+}

internal/util/new_retry/retry.go

@@ -0,0 +1,71 @@
+// Copyright (C) 2019-2020 Zilliz. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software distributed under the License
+// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+// or implied. See the License for the specific language governing permissions and limitations under the License.
+
+package retry
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+)
+
+func Do(ctx context.Context, fn func() error, opts ...Option) error {
+
+	c := NewDefaultConfig()
+
+	for _, opt := range opts {
+		opt(c)
+	}
+	el := make(ErrorList, c.attempts)
+
+	for i := uint(0); i < c.attempts; i++ {
+		if err := fn(); err != nil {
+			if s, ok := err.(InterruptError); ok {
+				return s.error
+			}
+			el[i] = err
+
+			select {
+			case <-time.After(c.sleep):
+			case <-ctx.Done():
+				return ctx.Err()
+			}
+
+			c.sleep *= 2
+			if c.sleep > c.maxSleepTime {
+				c.sleep = c.maxSleepTime
+			}
+		} else {
+			return nil
+		}
+	}
+	return el
+}
+
+type ErrorList []error
+
+func (el ErrorList) Error() string {
+	var builder strings.Builder
+	builder.WriteString("All attempts results:\n")
+	for index, err := range el {
+		builder.WriteString(fmt.Sprintf("attempt #%d:%s\n", index+1, err.Error()))
+	}
+	return builder.String()
+}
+
+type InterruptError struct {
+	error
+}
+
+func NoRetryError(err error) InterruptError {
+	return InterruptError{err}
+}

internal/util/new_retry/retry_test.go

@@ -0,0 +1,115 @@
+// Copyright (C) 2019-2020 Zilliz. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software distributed under the License
+// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+// or implied. See the License for the specific language governing permissions and limitations under the License.
+
+package retry
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDo(t *testing.T) {
+	ctx := context.Background()
+
+	n := 0
+	testFn := func() error {
+		if n < 3 {
+			n++
+			return fmt.Errorf("some error")
+		}
+		return nil
+	}
+
+	err := Do(ctx, testFn)
+	assert.Nil(t, err)
+}
+
+func TestAttempts(t *testing.T) {
+	ctx := context.Background()
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	err := Do(ctx, testFn, Attempts(1))
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}
+
+func TestMaxSleepTime(t *testing.T) {
+	ctx := context.Background()
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	err := Do(ctx, testFn, Attempts(3), MaxSleepTime(200*time.Millisecond))
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}
+
+func TestSleep(t *testing.T) {
+	ctx := context.Background()
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	err := Do(ctx, testFn, Attempts(3), Sleep(500*time.Millisecond))
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}
+
+func TestAllError(t *testing.T) {
+	ctx := context.Background()
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	err := Do(ctx, testFn, Attempts(3))
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}
+
+func TestContextDeadline(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+	defer cancel()
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	err := Do(ctx, testFn)
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}
+
+func TestContextCancel(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+
+	testFn := func() error {
+		return fmt.Errorf("some error")
+	}
+
+	go func() {
+		time.Sleep(1 * time.Second)
+		cancel()
+	}()
+
+	err := Do(ctx, testFn)
+	assert.NotNil(t, err)
+	fmt.Println(err)
+}

internal/util/retry/options.go

@@ -0,0 +1,48 @@
+// Copyright (C) 2019-2020 Zilliz. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance
+// with the License. You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software distributed under the License
+// is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+// or implied. See the License for the specific language governing permissions and limitations under the License.
+
+package retry
+
+import "time"
+
+type Config struct {
+	attempts     uint
+	sleep        time.Duration
+	maxSleepTime time.Duration
+}
+
+func NewDefaultConfig() *Config {
+	return &Config{
+		attempts:     uint(10),
+		sleep:        200 * time.Millisecond,
+		maxSleepTime: 1 * time.Second,
+	}
+}
+
+type Option func(*Config)
+
+func Attempts(attempts uint) Option {
+	return func(c *Config) {
+		c.attempts = attempts
+	}
+}
+
+func Sleep(sleep time.Duration) Option {
+	return func(c *Config) {
+		c.sleep = sleep
+	}
+}
+
+func MaxSleepTime(maxSleepTime time.Duration) Option {
+	return func(c *Config) {
+		c.maxSleepTime = maxSleepTime
+	}
+}