Golang QueryProcessor.YieldSeries方法代碼示例

func (self *CoordinatorImpl) readFromResposneChannels(processor cluster.QueryProcessor,
	writer SeriesWriter,
	isExplainQuery bool,
	errors chan<- error,
	channels <-chan (<-chan *protocol.Response)) {

	defer close(errors)

	for responseChan := range channels {
		for response := range responseChan {

			//log.Debug("GOT RESPONSE: ", response.Type, response.Series)
			log.Debug("GOT RESPONSE: ", response.Type)
			if *response.Type == endStreamResponse || *response.Type == accessDeniedResponse {
				if response.ErrorMessage == nil {
					break
				}

				err := common.NewQueryError(common.InvalidArgument, *response.ErrorMessage)
				log.Error("Error while executing query: %s", err)
				errors <- err
				return
			}

			if response.Series == nil || len(response.Series.Points) == 0 {
				log.Debug("Series has no points, continue")
				continue
			}

			// if we don't have a processor, yield the point to the writer
			// this happens if shard took care of the query
			// otherwise client will get points from passthrough engine
			if processor != nil {
				// if the data wasn't aggregated at the shard level, aggregate
				// the data here
				log.Debug("YIELDING: %d points with %d columns", len(response.Series.Points), len(response.Series.Fields))
				processor.YieldSeries(response.Series)
				continue
			}

			// If we have EXPLAIN query, we don't write actual points (of
			// response.Type Query) to the client
			if !(*response.Type == queryResponse && isExplainQuery) {
				writer.Write(response.Series)
			}
		}

		// once we're done with a response channel signal queryShards to
		// start querying a new shard
		errors <- nil
	}
	return
}

//.........這裏部分代碼省略.........
		// and sequence number. that will become the timestamp and sequence of
		// the next point.
		for _, value := range rawColumnValues {
			if value.value == nil {
				continue
			}

			pointTimeRaw, pointSequenceRaw = value.updatePointTimeAndSequence(pointTimeRaw,
				pointSequenceRaw, query.Ascending)
		}

		for i, iterator := range iterators {
			// if the value is nil or doesn't match the point's timestamp and sequence number
			// then skip it
			if rawColumnValues[i].value == nil ||
				!bytes.Equal(rawColumnValues[i].time, pointTimeRaw) ||
				!bytes.Equal(rawColumnValues[i].sequence, pointSequenceRaw) {

				point.Values[i] = &protocol.FieldValue{IsNull: &TRUE}
				continue
			}

			// if we emitted at lease one column, then we should keep
			// trying to get more points
			isValid = true

			// advance the iterator to read a new value in the next iteration
			if query.Ascending {
				iterator.Next()
			} else {
				iterator.Prev()
			}

			fv := &protocol.FieldValue{}
			valueBuffer.SetBuf(rawColumnValues[i].value)
			err := valueBuffer.Unmarshal(fv)
			if err != nil {
				log.Error("Error while running query: %s", err)
				return err
			}
			point.Values[i] = fv
			rawColumnValues[i].value = nil
		}

		var sequence uint64
		var t uint64

		// set the point sequence number and timestamp
		buffer.Reset()
		buffer.Write(pointSequenceRaw)
		binary.Read(buffer, binary.BigEndian, &sequence)
		buffer.Reset()
		buffer.Write(pointTimeRaw)
		binary.Read(buffer, binary.BigEndian, &t)

		time := self.convertUintTimestampToInt64(&t)
		point.SetTimestampInMicroseconds(time)
		point.SequenceNumber = &sequence

		// stop the loop if we ran out of points
		if !isValid {
			break
		}

		shouldContinue := true

		seriesOutgoing.Points = append(seriesOutgoing.Points, point)

		if len(seriesOutgoing.Points) >= self.pointBatchSize {
			for _, alias := range aliases {
				series := &protocol.Series{
					Name:   proto.String(alias),
					Fields: fieldNames,
					Points: seriesOutgoing.Points,
				}
				if !processor.YieldSeries(series) {
					log.Info("Stopping processing")
					shouldContinue = false
				}
			}
			seriesOutgoing = &protocol.Series{Name: protocol.String(seriesName), Fields: fieldNames, Points: make([]*protocol.Point, 0, self.pointBatchSize)}
		}

		if !shouldContinue {
			break
		}
	}

	//Yield remaining data
	for _, alias := range aliases {
		log.Debug("Final Flush %s", alias)
		series := &protocol.Series{Name: protocol.String(alias), Fields: seriesOutgoing.Fields, Points: seriesOutgoing.Points}
		if !processor.YieldSeries(series) {
			log.Debug("Cancelled...")
		}
	}

	log.Debug("Finished running query %s", query.GetQueryString())
	return nil
}