Fixed build issue and code comments

Signed-off-by: Florent Poinsard <florent.poinsard@outlook.fr>

go/vt/discovery/utils.go

@@ -24,8 +24,7 @@ import (
 )
 
 // This file contains helper filter methods to process the unfiltered list of
-// tablets returned by LegacyHealthCheck.GetTabletStatsFrom*.
-// See also legacy_replicationlag.go for a more sophisicated filter used by vtgate.
+// tablets returned by HealthCheckImpl.GetTabletHealth*.
 
 func TabletHealthReferenceListToValue(thl []*TabletHealth) []TabletHealth {
  newTh := []TabletHealth{}

go/vt/throttler/demo/throttler_demo.go

@@ -277,8 +277,7 @@ func (c *client) stop() {
  c.throttler.Close()
 }
 
-// StatsUpdate implements discovery.LegacyHealthCheckStatsListener.
-// It gets called by the healthCheck instance every time a tablet broadcasts
+// StatsUpdate gets called by the healthCheck instance every time a tablet broadcasts
 // a health update.
 func (c *client) StatsUpdate(ts *discovery.TabletHealth) {
  // Ignore unless REPLICA or RDONLY.

go/vt/throttler/max_replication_lag_module.go

@@ -54,7 +54,7 @@ const (
 // i.e. we'll ignore lag records with lower lag from other replicas while we're
 // waiting for the next record of this replica under test.
 type replicaUnderTest struct {
- // key holds the discovery.LegacyTabletStats.Key value for the replica.
+ // key holds the key value for the replica.
  key string
  alias string
  tabletType topodatapb.TabletType
@@ -114,8 +114,8 @@ type MaxReplicationLagModule struct {
  // max rate calculation has changed. The field is immutable (set in Start().)
  rateUpdateChan chan<- struct{}
 
- // lagRecords buffers the replication lag records received by the LegacyHealthCheck
- // listener. ProcessRecords() will process them.
+ // lagRecords buffers the replication lag records received by the HealthCheck
+ // subscriber. ProcessRecords() will process them.
  lagRecords chan replicationLagRecord
  wg sync.WaitGroup
 
@@ -246,7 +246,7 @@ func (m *MaxReplicationLagModule) RecordReplicationLag(t time.Time, th *discover
  }
  m.mutableConfigMu.Unlock()
 
- // Buffer data point for now to unblock the LegacyHealthCheck listener and process
+ // Buffer data point for now to unblock the HealthCheck subscriber and process
  // it asynchronously in ProcessRecords().
  m.lagRecords <- replicationLagRecord{t, *th}
 }
@@ -402,7 +402,7 @@ func (m *MaxReplicationLagModule) clearReplicaUnderTest(now time.Time, testedSta
  return true, "it is no longer actively tracked"
  }
  if lr.LastError != nil {
- // LastError is set i.e. LegacyHealthCheck module cannot connect and the cached
+ // LastError is set i.e. HealthCheck module cannot connect and the cached
  // data for the replica might be outdated.
  return true, "it has LastError set i.e. is no longer correctly tracked"
  }

go/vt/throttler/max_replication_lag_module_test.go

@@ -225,7 +225,7 @@ func TestMaxReplicationLagModule_ReplicaUnderTest_LastErrorOrNotUp(t *testing.T)
 
  // r2 @ 75s, 0s lag, LastError set
  rError := lagRecord(sinceZero(75*time.Second), r2, 0)
- rError.LastError = errors.New("LegacyHealthCheck reporting broken")
+ rError.LastError = errors.New("HealthCheck reporting broken")
  tf.m.replicaLagCache.add(rError)
 
  // r1 @ 110s, 0s lag

go/vt/throttler/replication_lag_cache.go

@@ -126,7 +126,7 @@ func (c *replicationLagCache) sortByLag(ignoreNSlowestReplicas int, minimumRepli
  }
 }
 
-// byLagAndTabletUID is a slice of discovery.LegacyTabletStats elements that
+// byLagAndTabletUID is a slice of discovery.TabletHealth elements that
 // implements sort.Interface to sort by replication lag and tablet Uid.
 type byLagAndTabletUID []discovery.TabletHealth
 

go/vt/throttler/replication_lag_record.go

@@ -23,7 +23,7 @@ import (
 )
 
 // replicationLagRecord stores the tablet health data for a given point in time.
-// This data is obtained via the LegacyHealthCheck module.
+// This data is obtained via the HealthCheck module.
 type replicationLagRecord struct {
  // time is the time at which "value" was observed.
  time time.Time

go/vt/vtctld/api.go

@@ -62,7 +62,7 @@ const (
  jsonContentType = "application/json; charset=utf-8"
 )
 
-// TabletStats represents realtime stats from a discovery.LegacyTabletStats struct.
+// TabletStats represents realtime stats from a discovery.TabletHealth struct.
 type TabletStats struct {
  LastError string `json:"last_error,omitempty"`
  Realtime *querypb.RealtimeStats `json:"realtime,omitempty"`

go/vt/vtgate/buffer/buffer.go

@@ -93,7 +93,7 @@ type Buffer struct {
  // In particular, it is used to serialize the following Go routines:
  // - 1. Requests which may buffer (RLock, can be run in parallel)
  // - 2. Request which starts buffering (based on the seen error)
- // - 3. LegacyHealthCheck listener ("StatsUpdate") which stops buffering
+ // - 3. HealthCheck subscriber ("StatsUpdate") which stops buffering
  // - 4. Timer which may stop buffering after -buffer_max_failover_duration
  mu sync.RWMutex
  // buffers holds a shardBuffer object per shard, even if no failover is in
@@ -171,29 +171,6 @@ func (b *Buffer) HandleKeyspaceEvent(ksevent *discovery.KeyspaceEvent) {
  }
 }
 
-// StatsUpdate keeps track of the "tablet_externally_reparented_timestamp" of
-// each primary. This way we can detect the end of a failover.
-// It is part of the discovery.LegacyHealthCheckStatsListener interface.
-func (b *Buffer) StatsUpdate(ts *discovery.LegacyTabletStats) {
- if ts.Target.TabletType != topodatapb.TabletType_PRIMARY {
- panic(fmt.Sprintf("BUG: non-PRIMARY LegacyTabletStats object must not be forwarded: %#v", ts))
- }
-
- timestamp := ts.TabletExternallyReparentedTimestamp
- if timestamp == 0 {
- // Primarys where TabletExternallyReparented was never called will return 0.
- // Ignore them.
- return
- }
-
- sb := b.getOrCreateBuffer(ts.Target.Keyspace, ts.Target.Shard)
- if sb == nil {
- // Buffer is shut down. Ignore all calls.
- return
- }
- sb.recordExternallyReparentedTimestamp(timestamp, ts.Tablet.Alias)
-}
-
 // getOrCreateBuffer returns the ShardBuffer for the given keyspace and shard.
 // It returns nil if Buffer is shut down and all calls should be ignored.
 func (b *Buffer) getOrCreateBuffer(keyspace, shard string) *shardBuffer {

go/vt/vtgate/buffer/buffer_helper_test.go

@@ -31,17 +31,6 @@ func testAllImplementations(t *testing.T, runTest func(t *testing.T, fail failov
  })
  })
 
- t.Run("LegacyHealthCheck", func(t *testing.T) {
- t.Helper()
- runTest(t, func(buf *Buffer, tablet *topodatapb.Tablet, keyspace, shard string, now time.Time) {
- buf.StatsUpdate(&discovery.LegacyTabletStats{
- Tablet: tablet,
- Target: &query.Target{Keyspace: keyspace, Shard: shard, TabletType: topodatapb.TabletType_PRIMARY},
- TabletExternallyReparentedTimestamp: now.Unix(),
- })
- })
- })
-
  t.Run("KeyspaceEvent", func(t *testing.T) {
  t.Helper()
  runTest(t, func(buf *Buffer, tablet *topodatapb.Tablet, keyspace, shard string, now time.Time) {

go/vt/vtgate/executor_test.go

@@ -776,8 +776,6 @@ func TestExecutorShow(t *testing.T) {
  }
  utils.MustMatch(t, wantqr, qr, query)
 
- // The FakeLegacyTablets in FakeLegacyHealthCheck don't have support for these columns/values
- // So let's just be sure the statement works and we get the expected results (none)
  query = "show vitess_replication_status"
  qr, err = executor.Execute(ctx, "TestExecute", session, query, nil)
  require.NoError(t, err)

go/vt/vtgate/vtgate.go

@@ -141,7 +141,6 @@ type VTGate struct {
  vsm *vstreamManager
  txConn *TxConn
  gw *TabletGateway
- pv plancontext.PlannerVersion
 
  // stats objects.
  // TODO(sougou): This needs to be cleaned up. There

go/vt/vttablet/tabletserver/txthrottler/tx_throttler.go

@@ -41,7 +41,7 @@ import (
 
 // TxThrottler throttles transactions based on replication lag.
 // It's a thin wrapper around the throttler found in vitess/go/vt/throttler.
-// It uses a discovery.LegacyHealthCheck to send replication-lag updates to the wrapped throttler.
+// It uses a discovery.HealthCheck to send replication-lag updates to the wrapped throttler.
 //
 // Intended Usage:
 // // Assuming topoServer is a topo.Server variable pointing to a Vitess topology server.
@@ -348,7 +348,7 @@ func (ts *txThrottlerState) deallocateResources() {
  ts.throttler = nil
 }
 
-// StatsUpdate is part of the LegacyHealthCheckStatsListener interface.
+// StatsUpdate updates the health of a tablet with the given healthcheck.
 func (ts *txThrottlerState) StatsUpdate(tabletStats *discovery.TabletHealth) {
  // Ignore PRIMARY and RDONLY stats.
  // We currently do not monitor RDONLY tablets for replication lag. RDONLY tablets are not

go/vt/worker/executor.go

@@ -185,7 +185,7 @@ func (e *executor) fetchWithRetries(ctx context.Context, action func(ctx context
  }
  return vterrors.Wrapf(err, "interrupted while trying to run a command on tablet %v", tabletString)
  case <-time.After(*executeFetchRetryTime):
- // Retry 30s after the failure using the current primary seen by the LegacyHealthCheck.
+ // Retry 30s after the failure using the current primary seen by the HealthCheck.
  }
  isRetry = true
  }

go/vt/worker/split_clone.go

@@ -422,7 +422,7 @@ func (scw *SplitCloneWorker) Run(ctx context.Context) error {
  // After Close returned, we can be sure that it won't call our listener
  // implementation (method StatsUpdate) anymore.
  if err := scw.healthCheck.Close(); err != nil {
- scw.wr.Logger().Errorf2(err, "LegacyHealthCheck.Close() failed")
+ scw.wr.Logger().Errorf2(err, "HealthCheck.Close() failed")
  }
  }
 
@@ -859,7 +859,7 @@ func (scw *SplitCloneWorker) findDestinationPrimarys(ctx context.Context) error
  }
  primarys := scw.healthCheck.GetHealthyTabletStats(&querypb.Target{Keyspace: si.Keyspace(), Shard: si.ShardName(), TabletType: topodatapb.TabletType_PRIMARY})
  if len(primarys) == 0 {
- return vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "cannot find PRIMARY tablet for destination shard for %v/%v (in cell: %v) in LegacyHealthCheck: empty LegacyTabletStats list", si.Keyspace(), si.ShardName(), scw.cell)
+ return vterrors.Errorf(vtrpc.Code_FAILED_PRECONDITION, "cannot find PRIMARY tablet for destination shard for %v/%v (in cell: %v) in HealthCheck: empty TabletHealth list", si.Keyspace(), si.ShardName(), scw.cell)
  }
  primary := primarys[0]
 
@@ -869,7 +869,7 @@ func (scw *SplitCloneWorker) findDestinationPrimarys(ctx context.Context) error
 
  scw.wr.Logger().Infof("Using tablet %v as destination primary for %v/%v", topoproto.TabletAliasString(primary.Tablet.Alias), si.Keyspace(), si.ShardName())
  }
- scw.wr.Logger().Infof("NOTE: The used primary of a destination shard might change over the course of the copy e.g. due to a reparent. The LegacyHealthCheck module will track and log primary changes and any error message will always refer the actually used primary address.")
+ scw.wr.Logger().Infof("NOTE: The used primary of a destination shard might change over the course of the copy e.g. due to a reparent. The HealthCheck module will track and log primary changes and any error message will always refer the actually used primary address.")
 
  return nil
 }
@@ -1357,13 +1357,9 @@ func (scw *SplitCloneWorker) createKeyResolver(td *tabletmanagerdatapb.TableDefi
  return newV3ResolverFromTableDefinition(scw.keyspaceSchema, td)
 }
 
-// StatsUpdate receives replication lag updates for each destination primary
+// StatsUpdate receives replication lag updates from the healthcheck for each destination primary
 // and forwards them to the respective throttler instance.
-// It also forwards any update to the LegacyTabletStatsCache to keep it up to date.
-// It is part of the discovery.LegacyHealthCheckStatsListener interface.
 func (scw *SplitCloneWorker) StatsUpdate(ts *discovery.TabletHealth) {
- // scw.tsc.StatsUpdate(ts)
-
  // Ignore unless REPLICA or RDONLY.
  if ts.Target.TabletType != topodatapb.TabletType_REPLICA && ts.Target.TabletType != topodatapb.TabletType_RDONLY {
  return

go/vt/worker/tablet_provider.go

@@ -75,7 +75,7 @@ func (p *singleTabletProvider) description() string {
 }
 
 // shardTabletProvider returns a random healthy RDONLY tablet for a given
-// keyspace and shard. It uses the LegacyHealthCheck module to retrieve the tablets.
+// keyspace and shard. It uses the HealthCheck module to retrieve the tablets.
 type shardTabletProvider struct {
  hc *discovery.HealthCheckImpl
  tracker *TabletTracker