69 lines
1.2 KiB
Go
69 lines
1.2 KiB
Go
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package mdb
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/*
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type follower struct {
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Stop chan struct{}
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Done *sync.WaitGroup
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WALRootDir string
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SeqNum uint64 // Current max applied sequence number.
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ApplyChanges func(rec *cswal.Record) error
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seqNum uint64 // Current max applied sequence number.
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}
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func (f *follower) Run() {
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defer f.Done.Done()
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f.seqNum = f.SeqNum
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for {
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f.runOnce()
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select {
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case <-f.Stop:
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return
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default:
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// Something went wrong.
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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 (f *follower) runOnce() {
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it, err := cswal.NewIterator(f.WALRootDir, f.seqNum+1)
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if err != nil {
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f.logf("Failed to get WAL iterator: %v", errs.FmtDetails(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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hasNext := it.Next(time.Second)
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select {
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case <-f.Stop:
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return
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default:
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}
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if !hasNext {
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if it.Error() != nil {
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f.logf("Iteration error: %v", errs.FmtDetails(it.Error()))
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return
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}
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continue
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}
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rec := it.Record()
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if err := f.ApplyChanges(rec); err != nil {
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f.logf("Failed to apply changes: %s", errs.FmtDetails(err))
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return
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}
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f.seqNum = rec.SeqNum
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}
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}
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func (f *follower) logf(pattern string, args ...interface{}) {
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log.Printf("[FOLLOWER] "+pattern, args...)
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}
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*/
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