gc_worker: Remove timezone name from the times that are saved in mysq…

…l.tidb (pingcap#8745)

Signed-off-by: MyonKeminta <MyonKeminta@users.noreply.github.com>

executor/admin_test.go

@@ -551,7 +551,7 @@ func (s *testSuite2) TestAdminCheckWithSnapshot(c *C) {
 
  // For mocktikv, safe point is not initialized, we manually insert it for snapshot to use.
  safePointName := "tikv_gc_safe_point"
- safePointValue := "20060102-15:04:05 -0700 MST"
+ safePointValue := "20060102-15:04:05 -0700"
  safePointComment := "All versions after safe point can be accessed. (DO NOT EDIT)"
  updateSafePoint := fmt.Sprintf(`INSERT INTO mysql.tidb VALUES ('%[1]s', '%[2]s', '%[3]s')
  ON DUPLICATE KEY

executor/executor_test.go

@@ -2021,7 +2021,7 @@ func (s *testSuite) TestHistoryRead(c *C) {
 
  // For mocktikv, safe point is not initialized, we manually insert it for snapshot to use.
  safePointName := "tikv_gc_safe_point"
- safePointValue := "20060102-15:04:05 -0700 MST"
+ safePointValue := "20060102-15:04:05 -0700"
  safePointComment := "All versions after safe point can be accessed. (DO NOT EDIT)"
  updateSafePoint := fmt.Sprintf(`INSERT INTO mysql.tidb VALUES ('%[1]s', '%[2]s', '%[3]s')
  ON DUPLICATE KEY

executor/set.go

@@ -17,7 +17,6 @@ import (
  "context"
  "fmt"
  "strings"
- "time"
 
  "github.com/pingcap/errors"
  "github.com/pingcap/parser/ast"
@@ -28,6 +27,7 @@ import (
  "github.com/pingcap/tidb/sessionctx"
  "github.com/pingcap/tidb/sessionctx/variable"
  "github.com/pingcap/tidb/types"
+ "github.com/pingcap/tidb/util"
  "github.com/pingcap/tidb/util/chunk"
  "github.com/pingcap/tidb/util/sqlexec"
  log "github.com/sirupsen/logrus"
@@ -194,8 +194,7 @@ func validateSnapshot(ctx sessionctx.Context, snapshotTS uint64) error {
  return errors.New("can not get 'tikv_gc_safe_point'")
  }
  safePointString := rows[0].GetString(0)
- const gcTimeFormat = "20060102-15:04:05 -0700 MST"
- safePointTime, err := time.Parse(gcTimeFormat, safePointString)
+ safePointTime, err := util.CompatibleParseGCTime(safePointString)
  if err != nil {
  return errors.Trace(err)
  }

store/tikv/gcworker/gc_worker.go

@@ -95,7 +95,6 @@ func (w *GCWorker) Close() {
 }
 
 const (
- gcTimeFormat = "20060102-15:04:05 -0700 MST"
  gcWorkerTickInterval = time.Minute
  gcJobLogTickInterval = time.Minute * 10
  gcWorkerLease = time.Minute * 2
@@ -932,7 +931,7 @@ func (w *GCWorker) saveSafePoint(kv tikv.SafePointKV, key string, t uint64) erro
 }
 
 func (w *GCWorker) saveTime(key string, t time.Time) error {
- err := w.saveValueToSysTable(key, t.Format(gcTimeFormat))
+ err := w.saveValueToSysTable(key, t.Format(tidbutil.GCTimeFormat))
  return errors.Trace(err)
 }
 
@@ -944,7 +943,7 @@ func (w *GCWorker) loadTime(key string) (*time.Time, error) {
  if str == "" {
  return nil, nil
  }
- t, err := time.Parse(gcTimeFormat, str)
+ t, err := tidbutil.CompatibleParseGCTime(str)
  if err != nil {
  return nil, errors.Trace(err)
  }
@@ -1078,7 +1077,7 @@ func NewMockGCWorker(store tikv.Storage) (*MockGCWorker, error) {
  return &MockGCWorker{worker: worker}, nil
 }
 
-// DeleteRanges call deleteRanges internally, just for test.
+// DeleteRanges calls deleteRanges internally, just for test.
 func (w *MockGCWorker) DeleteRanges(ctx context.Context, safePoint uint64) error {
  log.Errorf("deleteRanges is called")
  return w.worker.deleteRanges(ctx, safePoint)

util/misc.go

@@ -15,6 +15,7 @@ package util
 
 import (
  "runtime"
+ "strings"
  "time"
 
  "github.com/pingcap/errors"
@@ -26,6 +27,8 @@ const (
  DefaultMaxRetries = 30
  // RetryInterval indicates retry interval.
  RetryInterval uint64 = 500
+ // GCTimeFormat is the format that gc_worker used to store times.
+ GCTimeFormat = "20060102-15:04:05 -0700"
 )
 
 // RunWithRetry will run the f with backoff and retry.
@@ -72,3 +75,23 @@ func WithRecovery(exec func(), recoverFn func(r interface{})) {
  }()
  exec()
 }
+
+// CompatibleParseGCTime parses a string with `GCTimeFormat` and returns a time.Time. If `value` can't be parsed as that
+// format, truncate to last space and try again. This function is only useful when loading times that saved by
+// gc_worker. We have changed the format that gc_worker saves time (removed the last field), but when loading times it
+// should be compatible with the old format.
+func CompatibleParseGCTime(value string) (time.Time, error) {
+ t, err := time.Parse(GCTimeFormat, value)
+
+ if err != nil {
+ // Remove the last field that separated by space
+ parts := strings.Split(value, " ")
+ prefix := strings.Join(parts[:len(parts)-1], " ")
+ t, err = time.Parse(GCTimeFormat, prefix)
+ }
+
+ if err != nil {
+ err = errors.Errorf("string \"%v\" doesn't has a prefix that matches format \"%v\"", value, GCTimeFormat)
+ }
+ return t, err
+}

util/misc_test.go

@@ -14,6 +14,8 @@
 package util
 
 import (
+ "time"
+
  . "github.com/pingcap/check"
  "github.com/pingcap/errors"
  "github.com/pingcap/tidb/util/testleak"
@@ -30,7 +32,7 @@ func (s *testMiscSuite) SetUpSuite(c *C) {
 func (s *testMiscSuite) TearDownSuite(c *C) {
 }
 
-func (s testMiscSuite) TestRunWithRetry(c *C) {
+func (s *testMiscSuite) TestRunWithRetry(c *C) {
  defer testleak.AfterTest(c)()
  // Run succ.
  cnt := 0
@@ -68,3 +70,46 @@ func (s testMiscSuite) TestRunWithRetry(c *C) {
  c.Assert(err, NotNil)
  c.Assert(cnt, Equals, 1)
 }
+
+func (s *testMiscSuite) TestCompatibleParseGCTime(c *C) {
+ values := []string{
+ "20181218-19:53:37 +0800 CST",
+ "20181218-19:53:37 +0800 MST",
+ "20181218-19:53:37 +0800 FOO",
+ "20181218-19:53:37 +0800 +08",
+ "20181218-19:53:37 +0800",
+ "20181218-19:53:37 +0800 ",
+ "20181218-11:53:37 +0000",
+ }
+
+ invalidValues := []string{
+ "",
+ " ",
+ "foo",
+ "20181218-11:53:37",
+ "20181218-19:53:37 +0800CST",
+ "20181218-19:53:37 +0800 FOO BAR",
+ "20181218-19:53:37 +0800FOOOOOOO BAR",
+ "20181218-19:53:37 ",
+ }
+
+ expectedTime := time.Date(2018, 12, 18, 11, 53, 37, 0, time.UTC)
+ expectedTimeFormatted := "20181218-19:53:37 +0800"
+
+ beijing, err := time.LoadLocation("Asia/Shanghai")
+ c.Assert(err, IsNil)
+
+ for _, value := range values {
+ t, err := CompatibleParseGCTime(value)
+ c.Assert(err, IsNil)
+ c.Assert(t.Equal(expectedTime), Equals, true)
+
+ formatted := t.In(beijing).Format(GCTimeFormat)
+ c.Assert(formatted, Equals, expectedTimeFormatted)
+ }
+
+ for _, value := range invalidValues {
+ _, err := CompatibleParseGCTime(value)
+ c.Assert(err, NotNil)
+ }
+}