refactor: add debug info

xstream/nodes/sink_node.go

@@ -159,18 +159,22 @@ func (m *SinkNode) Open(ctx api.StreamContext, result chan<- error) {
 				var sink api.Sink
 				var err error
 				if !m.isMock {
+					logger.Debugf(fmt.Sprintf("Trying to get sink for rule %s with options %v\n", ctx.GetRuleId(), m.options))
 					sink, err = getSink(m.sinkType, m.options)
 					if err != nil {
 						m.drainError(result, err, ctx, logger)
 						return
 					}
+					logger.Debugf(fmt.Sprintf("Successfully get the sink %s", m.sinkType))
 					m.mutex.Lock()
 					m.sinks = append(m.sinks, sink)
 					m.mutex.Unlock()
+					logger.Debugf(fmt.Sprintf("Now is to open sink for rule %s.\n", ctx.GetRuleId()))
 					if err := sink.Open(ctx); err != nil {
 						m.drainError(result, err, ctx, logger)
 						return
 					}
+					logger.Debugf(fmt.Sprintf("Successfully open sink for rule %s.\n", ctx.GetRuleId()))
 				} else {
 					sink = m.sinks[instance]
 				}