67 lines
1.0 KiB
Go
67 lines
1.0 KiB
Go
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package rep
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import (
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"log"
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"time"
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)
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func (rep *Replicator) runWALFollower() {
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defer rep.done.Done()
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for {
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rep.followOnce()
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select {
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case <-rep.stop:
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return
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default:
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time.Sleep(time.Second)
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}
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}
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}
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func (rep *Replicator) followOnce() {
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logf := func(pattern string, args ...any) {
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log.Printf("[WAL-FOLLOWER] "+pattern, args...)
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}
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state := rep.getState()
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it, err := rep.wal.Iterator(state.SeqNum + 1)
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if err != nil {
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logf("Failed to create WAL iterator: %v", err)
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return
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}
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defer it.Close()
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for {
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select {
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case <-rep.stop:
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logf("Stopped")
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return
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default:
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}
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if it.Next(time.Second) {
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rec := it.Record()
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if err := rep.app.Apply(rec); err != nil {
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logf("App failed to apply change: %v", err)
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return
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}
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if err := rep.ack(rec.SeqNum, rec.TimestampMS); err != nil {
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logf("App failed to update local state: %v", err)
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return
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}
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select {
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case rep.appendNotify <- struct{}{}:
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default:
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}
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} else if it.Error() != nil {
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logf("Iteration error: %v", err)
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return
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}
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}
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}
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