54 lines
912 B
Go
54 lines
912 B
Go
package logging
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import (
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"context"
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)
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/*
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Logger implementation using the observable pattern.
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Implements io.Writer interface.
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The observable is an event source which drops everythigng unless there's
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a subscriber connected.
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The observer implementatios are a http ServerSentEvents handler and a
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websocket one in handler.go
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*/
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type ObservableLogger struct {
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logsChan chan []byte
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}
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func NewObservableLogger() *ObservableLogger {
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return &ObservableLogger{
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logsChan: make(chan []byte, 100),
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}
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}
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func (o *ObservableLogger) Write(p []byte) (n int, err error) {
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select {
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case o.logsChan <- p:
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n = len(p)
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err = nil
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return
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default:
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return
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}
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}
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func (o *ObservableLogger) Observe(ctx context.Context) <-chan string {
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logs := make(chan string)
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go func() {
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for {
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select {
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case <-ctx.Done():
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return
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case logLine := <-o.logsChan:
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logs <- string(logLine)
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}
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}
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}()
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return logs
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}
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