txn_test.go

// Copyright 2015 PingCAP, Inc.
//
// 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,
// See the License for the specific language governing permissions and
// limitations under the License.

package kv

import (
	"time"

	. "github.com/pingcap/check"
)

var _ = Suite(&testTxnSuite{})

type testTxnSuite struct {
}

func (s *testTxnSuite) SetUpTest(c *C) {
}

func (s *testTxnSuite) TearDownTest(c *C) {
}

func (s *testTxnSuite) TestBackOff(c *C) {
	mustBackOff(c, 1, 2)
	mustBackOff(c, 2, 4)
	mustBackOff(c, 3, 8)
	mustBackOff(c, 100000, 100)
}

func mustBackOff(c *C, cnt, sleep int) {
	c.Assert(BackOff(cnt), LessEqual, sleep*int(time.Millisecond))
}

// mockTxn is a txn that returns a retryAble error when called Commit.
type mockTxn struct {
}

// Always returns a retryable error
func (t *mockTxn) Commit() error {
	return ErrRetryable
}

func (t *mockTxn) Rollback() error {
	return nil
}

func (t *mockTxn) String() string {
	return ""
}

func (t *mockTxn) LockKeys(keys ...Key) error {
	return nil
}

func (t *mockTxn) SetOption(opt Option, val interface{}) {
	return
}

func (t *mockTxn) DelOption(opt Option) {
	return
}

func (t *mockTxn) IsReadOnly() bool {
	return true
}

func (t *mockTxn) GetClient() Client {
	return nil
}

func (t *mockTxn) StartTS() int64 {
	return int64(0)
}
func (t *mockTxn) Get(k Key) ([]byte, error) {
	return nil, nil
}

func (t *mockTxn) Seek(k Key) (Iterator, error) {
	return nil, nil
}

func (t *mockTxn) Set(k Key, v []byte) error {
	return nil
}
func (t *mockTxn) Delete(k Key) error {
	return nil
}

// mockStorage is used to start a must commit-failed txn
type mockStorage struct {
}

func (s *mockStorage) Begin() (Transaction, error) {
	return &mockTxn{}, nil

}
func (s *mockStorage) GetSnapshot(ver Version) (Snapshot, error) {
	return nil, nil
}
func (s *mockStorage) Close() error {
	return nil
}

func (s *mockStorage) UUID() string {
	return ""
}

// CurrentVersion returns current max committed version.
func (s *mockStorage) CurrentVersion() (Version, error) {
	return Version{uint64(1)}, nil
}

func (s *testTxnSuite) TestRetryExceedCountError(c *C) {
	maxRetryCnt = 5
	err := RunInNewTxn(&mockStorage{}, true, func(txn Transaction) error {
		return nil
	})
	c.Assert(err, NotNil)
	maxRetryCnt = 100
}