Function AddDebugFileSink

utils/log/logger.go:471–502

AddDebugFileSink returns a new logger that, in addition to whatever sinks the input logger already had, writes every debug-level-or-above entry to file via a 256 KiB buffered, capBytes-capped pipeline. Used by `keploy cloud replay` to capture the full debug stream for the support bundle without lift

(logger *zap.Logger, file *os.File, capBytes int64)

// Caller owns `file`. Call DebugFileSink.Flush before closing the file
// at end-of-run.
func AddDebugFileSink(logger *zap.Logger, file *os.File, capBytes int64) (*zap.Logger, *DebugFileSink) {
	if logger == nil || file == nil {
		return logger, nil
	}
	if capBytes <= 0 {
		capBytes = 100 << 20 // 100 MiB default
	}
	capped := newCappedWriteSyncer(zapcore.AddSync(file), capBytes)
	// FlushInterval defaults to 30s in zap, which is too coarse: a
	// short test set (e.g. 2 test cases finishing in < 30s) can write
	// less than the 256 KiB buffer size and never trigger an
	// auto-flush. If the agent process is then killed by
	// docker-compose teardown before main's defer runs Flush(), the
	// buffered bytes are LOST and the per-test-set file ends up
	// empty. 1s keeps the buffering performance benefit while
	// bounding data-loss-on-crash to ~1s of records.
	buffered := &zapcore.BufferedWriteSyncer{WS: capped, Size: 256 << 10, FlushInterval: time.Second}
	encoder := NewANSIConsoleEncoder(LogCfg.EncoderConfig)
	debugCore := newRedactingCore(zapcore.NewCore(
		encoder,
		wrapWriter(buffered),
		zap.NewAtomicLevelAt(zap.DebugLevel),
	))
	newLogger := logger.WithOptions(zap.WrapCore(func(c zapcore.Core) zapcore.Core {
		return zapcore.NewTee(c, debugCore)
	}))
	return newLogger, &DebugFileSink{
		capped:     capped,
		buffered:   buffered,
		originPath: file.Name(),
	}
}

// Swap atomically swaps the underlying file the sink writes to. The
// caller opens newFile; the previous file is returned so the caller