76 lines
1.3 KiB
Go
76 lines
1.3 KiB
Go
package monitor
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import (
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"sync"
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log "github.com/hashicorp/go-hclog"
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)
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type Monitor struct {
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sync.Mutex
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sink log.SinkAdapter
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logger log.InterceptLogger
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logCh chan []byte
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index int
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droppedCount int
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bufSize int
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}
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func New(buf int, logger log.InterceptLogger, opts *log.LoggerOptions) *Monitor {
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sw := &Monitor{
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logger: logger,
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logCh: make(chan []byte, buf),
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index: 0,
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bufSize: buf,
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}
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opts.Output = sw
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sink := log.NewSinkAdapter(opts)
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sw.sink = sink
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return sw
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}
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func (d *Monitor) Start(stopCh <-chan struct{}) <-chan []byte {
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d.logger.RegisterSink(d.sink)
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logCh := make(chan []byte, d.bufSize)
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go func() {
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for {
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select {
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case log := <-d.logCh:
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logCh <- log
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case <-stopCh:
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d.Lock()
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defer d.Unlock()
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d.logger.DeregisterSink(d.sink)
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close(d.logCh)
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return
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}
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}
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}()
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return logCh
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}
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// Write attemps to send latest log to logCh
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// it drops the log if channel is unavailable to receive
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func (d *Monitor) Write(p []byte) (n int, err error) {
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bytes := make([]byte, len(p))
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copy(bytes, p)
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select {
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case d.logCh <- bytes:
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default:
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d.Lock()
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defer d.Unlock()
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d.droppedCount++
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if d.droppedCount > 10 {
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d.logger.Warn("Monitor dropped %d logs during monitor request", d.droppedCount)
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d.droppedCount = 0
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}
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}
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return
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}
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