Golang common.NewQueryError函數代碼示例

func NewTopOrBottomAggregator(name string, v *parser.Value, isTop bool, defaultValue *parser.Value) (Aggregator, error) {
	if len(v.Elems) != 2 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, fmt.Sprintf("function %s() requires at exactly 2 arguments", name))
	}

	if v.Elems[1].Type != parser.ValueInt {
		return nil, common.NewQueryError(common.InvalidArgument, fmt.Sprintf("function %s() second parameter expect int", name))
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	limit, err := strconv.ParseInt(v.Elems[1].Name, 10, 64)
	if err != nil {
		return nil, err
	}

	if limit < 1 {
		return nil, common.NewQueryError(common.InvalidArgument, fmt.Sprintf("function %s() second parameter must be > 0", name))
	}

	return &TopOrBottomAggregator{
		AbstractAggregator: AbstractAggregator{
			value: v.Elems[0],
		},
		name:         name,
		isTop:        isTop,
		defaultValue: wrappedDefaultValue,
		alias:        v.Alias,
		limit:        limit}, nil
}

func NewCountAggregator(q *parser.SelectQuery, v *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(v.Elems) != 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function count() requires exactly one argument")
	}

	if v.Elems[0].Type == parser.ValueWildcard {
		return nil, common.NewQueryError(common.InvalidArgument, "function count() doesn't work with wildcards")
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	if v.Elems[0].Type != parser.ValueSimpleName {
		innerName := strings.ToLower(v.Elems[0].Name)
		init := registeredAggregators[innerName]
		if init == nil {
			return nil, common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Unknown function %s", innerName))
		}
		inner, err := init(q, v.Elems[0], defaultValue)
		if err != nil {
			return nil, err
		}
		return NewCompositeAggregator(&CountAggregator{AbstractAggregator{}, wrappedDefaultValue, v.Alias}, inner)
	}

	return &CountAggregator{AbstractAggregator{}, wrappedDefaultValue, v.Alias}, nil
}

func NewPercentileAggregator(_ *parser.SelectQuery, value *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(value.Elems) != 2 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function percentile() requires exactly two arguments")
	}

	if value.Elems[0].Type == parser.ValueWildcard {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "wildcard cannot be used with percentile")
	}

	percentile, err := strconv.ParseFloat(value.Elems[1].Name, 64)

	if err != nil || percentile <= 0 || percentile >= 100 {
		return nil, common.NewQueryError(common.InvalidArgument, "function percentile() requires a numeric second argument between 0 and 100")
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	functionName := "percentile"
	if value.Alias != "" {
		functionName = value.Alias
	}

	return &PercentileAggregator{
		AbstractAggregator: AbstractAggregator{
			value: value.Elems[0],
		},
		functionName: functionName,
		percentile:   percentile,
		defaultValue: wrappedDefaultValue,
	}, nil
}

func NewDerivativeAggregator(q *parser.SelectQuery, v *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(v.Elems) != 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function derivative() requires exactly one argument")
	}

	if v.Elems[0].Type == parser.ValueWildcard {
		return nil, common.NewQueryError(common.InvalidArgument, "function derivative() doesn't work with wildcards")
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	da := &DerivativeAggregator{
		AbstractAggregator: AbstractAggregator{
			value: v.Elems[0],
		},
		defaultValue: wrappedDefaultValue,
		alias:        v.Alias,
	}

	da.duration, _, err = q.GetGroupByClause().GetGroupByTime()
	if err != nil {
		return nil, err
	}

	return da, nil
}

func (self *QueryEngine) executeCountQueryWithGroupBy(query *parser.SelectQuery, yield func(*protocol.Series) error) error {
	self.aggregateYield = yield
	duration, err := query.GetGroupByClause().GetGroupByTime()
	if err != nil {
		return err
	}

	self.isAggregateQuery = true
	self.duration = duration
	self.aggregators = []Aggregator{}

	for _, value := range query.GetColumnNames() {
		if !value.IsFunctionCall() {
			continue
		}
		lowerCaseName := strings.ToLower(value.Name)
		initializer := registeredAggregators[lowerCaseName]
		if initializer == nil {
			return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Unknown function %s", value.Name))
		}
		aggregator, err := initializer(query, value, query.GetGroupByClause().FillValue)
		if err != nil {
			return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("%s", err))
		}
		self.aggregators = append(self.aggregators, aggregator)
	}

	for _, elem := range query.GetGroupByClause().Elems {
		if elem.IsFunctionCall() {
			continue
		}
		self.elems = append(self.elems, elem)
	}

	self.fillWithZero = query.GetGroupByClause().FillWithZero

	// This is a special case for issue #426. If the start time is
	// specified and there's a group by clause and fill with zero, then
	// we need to fill the entire range from start time to end time
	if query.IsStartTimeSpecified() && self.duration != nil && self.fillWithZero {
		self.startTimeSpecified = true
		self.startTime = query.GetStartTime().Truncate(*self.duration).UnixNano() / 1000
		self.endTime = query.GetEndTime().Truncate(*self.duration).UnixNano() / 1000
	}

	self.initializeFields()

	err = self.distributeQuery(query, func(series *protocol.Series) error {
		if len(series.Points) == 0 {
			return nil
		}

		return self.aggregateValuesForSeries(series)
	})

	return err
}

func NewAggregatorEngine(query *parser.SelectQuery, next Processor) (*AggregatorEngine, error) {
	ae := &AggregatorEngine{
		next:         next,
		seriesStates: make(map[string]*SeriesState),
		ascending:    query.Ascending,
	}

	var err error
	ae.duration, ae.irregularInterval, err = query.GetGroupByClause().GetGroupByTime()
	if err != nil {
		return nil, err
	}

	ae.aggregators = []Aggregator{}

	for _, value := range query.GetColumnNames() {
		if !value.IsFunctionCall() {
			continue
		}
		lowerCaseName := strings.ToLower(value.Name)
		initializer := registeredAggregators[lowerCaseName]
		if initializer == nil {
			return nil, common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Unknown function %s", value.Name))
		}
		aggregator, err := initializer(query, value, query.GetGroupByClause().FillValue)
		if err != nil {
			return nil, common.NewQueryError(common.InvalidArgument, fmt.Sprintf("%s", err))
		}
		ae.aggregators = append(ae.aggregators, aggregator)
	}

	for _, elem := range query.GetGroupByClause().Elems {
		if elem.IsFunctionCall() {
			continue
		}
		ae.elems = append(ae.elems, elem)
	}

	ae.isFillQuery = query.GetGroupByClause().FillWithZero

	// This is a special case for issue #426. If the start time is
	// specified and there's a group by clause and fill with zero, then
	// we need to fill the entire range from start time to end time
	if query.IsStartTimeSpecified() && ae.duration != nil && ae.isFillQuery {
		ae.startTimeSpecified = true
		ae.startTime = query.GetStartTime().Truncate(*ae.duration).UnixNano() / 1000
		ae.endTime = query.GetEndTime().Truncate(*ae.duration).UnixNano() / 1000
	}

	ae.initializeFields()

	return ae, nil
}

func (self *QueryEngine) executeCountQueryWithGroupBy(query *parser.SelectQuery, yield func(*protocol.Series) error) error {
	self.aggregateYield = yield
	duration, err := query.GetGroupByClause().GetGroupByTime()
	if err != nil {
		return err
	}

	self.isAggregateQuery = true
	self.duration = duration
	self.aggregators = []Aggregator{}

	for _, value := range query.GetColumnNames() {
		if !value.IsFunctionCall() {
			continue
		}
		lowerCaseName := strings.ToLower(value.Name)
		initializer := registeredAggregators[lowerCaseName]
		if initializer == nil {
			return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("Unknown function %s", value.Name))
		}
		aggregator, err := initializer(query, value, query.GetGroupByClause().FillValue)
		if err != nil {
			return common.NewQueryError(common.InvalidArgument, fmt.Sprintf("%s", err))
		}
		self.aggregators = append(self.aggregators, aggregator)
	}

	for _, elem := range query.GetGroupByClause().Elems {
		if elem.IsFunctionCall() {
			continue
		}
		self.elems = append(self.elems, elem)
	}

	self.fillWithZero = query.GetGroupByClause().FillWithZero

	self.initializeFields()

	err = self.distributeQuery(query, func(series *protocol.Series) error {
		if len(series.Points) == 0 {
			return nil
		}

		return self.aggregateValuesForSeries(series)
	})

	return err
}

// Process responses from the given channel. Returns true if
// processing should stop for other channels. False otherwise.
func (p *MergeChannelProcessor) processChannel(channel <-chan *protocol.Response) bool {
	for response := range channel {
		log4go.Debug("%s received %s", p, response)

		switch rt := response.GetType(); rt {

		// all these types end the stream
		case protocol.Response_HEARTBEAT,
			protocol.Response_END_STREAM:
			p.e <- nil
			return false

		case protocol.Response_ERROR:
			err := common.NewQueryError(common.InvalidArgument, response.GetErrorMessage())
			p.e <- err
			return false

		case protocol.Response_QUERY:
			for _, s := range response.MultiSeries {
				log4go.Debug("Yielding to %s: %s", p.next.Name(), s)
				_, err := p.next.Yield(s)
				if err != nil {
					p.e <- err
					return true
				}
			}

		default:
			panic(fmt.Errorf("Unknown response type: %s", rt))
		}
	}
	panic(errors.New("Reached end of method"))
}

func NewMedianAggregator(_ *parser.SelectQuery, value *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(value.Elems) != 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function median() requires exactly one argument")
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	functionName := "median"
	if value.Alias != "" {
		functionName = value.Alias
	}

	aggregator := &PercentileAggregator{
		AbstractAggregator: AbstractAggregator{
			value: value.Elems[0],
		},
		functionName: functionName,
		percentile:   50.0,
		defaultValue: wrappedDefaultValue,
		alias:        value.Alias,
	}
	return aggregator, nil
}

func NewModeAggregator(_ *parser.SelectQuery, value *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(value.Elems) < 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function mode() requires at least one argument")
	}

	// TODO: Mode can in fact take two argument, the second specifies
	// the "size", but it's not clear if size is set to 2 whether to
	// return at least 2 elements, or return the most common values and
	// the second most common values. The difference will be apparent if
	// the data set is multimodel and there are two most common
	// values. In the first case, the two most common values will be
	// returned, but in the second case the two most common values and
	// the second most common values will be returned
	if len(value.Elems) > 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function mode() takes at most one arguments")
	}

	size := 1
	if len(value.Elems) == 2 {
		switch value.Elems[1].Type {
		case parser.ValueInt:
			var err error
			size, err = strconv.Atoi(value.Elems[1].Name)
			if err != nil {
				return nil, common.NewQueryError(common.InvalidArgument, "Cannot parse %s into an int", value.Elems[1].Name)
			}
		default:
			return nil, common.NewQueryError(common.InvalidArgument, "Cannot parse %s into a int", value.Elems[1].Name)
		}
	}

	wrappedDefaultValue, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}

	return &ModeAggregator{
		AbstractAggregator: AbstractAggregator{
			value: value.Elems[0],
		},
		defaultValue: wrappedDefaultValue,
		alias:        value.Alias,
		size:         size,
	}, nil
}

func HashPassword(password string) ([]byte, error) {
	if length := len(password); length < 4 || length > 56 {
		return nil, common.NewQueryError(common.InvalidArgument, "Password must be more than 4 and less than 56 characters")
	}

	// The second arg is the cost of the hashing, higher is slower but makes it harder
	// to brute force, since it will be really slow and impractical
	return bcrypt.GenerateFromPassword([]byte(password), 10)
}

func (self *CoordinatorImpl) runQuerySpec(querySpec *parser.QuerySpec, seriesWriter SeriesWriter) error {
	shards, processor, seriesClosed, err := self.getShardsAndProcessor(querySpec, seriesWriter)
	if err != nil {
		return err
	}

	if len(shards) == 0 {
		return fmt.Errorf("Couldn't look up columns")
	}

	defer func() {
		if processor != nil {
			processor.Close()
			<-seriesClosed
		} else {
			seriesWriter.Close()
		}
	}()

	shardConcurrentLimit := self.config.ConcurrentShardQueryLimit
	if self.shouldQuerySequentially(shards, querySpec) {
		log.Debug("Querying shards sequentially")
		shardConcurrentLimit = 1
	}
	log.Debug("Shard concurrent limit: %d", shardConcurrentLimit)

	errors := make(chan error, shardConcurrentLimit)
	for i := 0; i < shardConcurrentLimit; i++ {
		errors <- nil
	}
	responseChannels := make(chan (<-chan *protocol.Response), shardConcurrentLimit)

	go self.readFromResponseChannels(processor, seriesWriter, querySpec.IsExplainQuery(), errors, responseChannels)

	err = self.queryShards(querySpec, shards, errors, responseChannels)

	// make sure we read the rest of the errors and responses
	for _err := range errors {
		if err == nil {
			err = _err
		}
	}

	for responsechan := range responseChannels {
		for response := range responsechan {
			if response.GetType() != endStreamResponse {
				continue
			}
			if response.ErrorMessage != nil && err == nil {
				err = common.NewQueryError(common.InvalidArgument, *response.ErrorMessage)
			}
			break
		}
	}
	return err
}

func NewHistogramAggregator(q *parser.SelectQuery, v *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(v.Elems) < 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function histogram() requires at least one arguments")
	}

	if len(v.Elems) > 2 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function histogram() takes at most two arguments")
	}

	if v.Elems[0].Type == parser.ValueWildcard {
		return nil, common.NewQueryError(common.InvalidArgument, "function histogram() doesn't work with wildcards")
	}

	bucketSize := 1.0

	if len(v.Elems) == 2 {
		switch v.Elems[1].Type {
		case parser.ValueInt, parser.ValueFloat:
			var err error
			bucketSize, err = strconv.ParseFloat(v.Elems[1].Name, 64)
			if err != nil {
				return nil, common.NewQueryError(common.InvalidArgument, "Cannot parse %s into a float", v.Elems[1].Name)
			}
		default:
			return nil, common.NewQueryError(common.InvalidArgument, "Cannot parse %s into a float", v.Elems[1].Name)
		}
	}

	columnNames := []string{"bucket_start", "count"}
	if v.Alias != "" {
		columnNames[0] = fmt.Sprintf("%s_bucket_start", v.Alias)
		columnNames[1] = fmt.Sprintf("%s_count", v.Alias)
	}

	return &HistogramAggregator{
		AbstractAggregator: AbstractAggregator{
			value: v.Elems[0],
		},
		bucketSize:  bucketSize,
		columnNames: columnNames,
	}, nil
}

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

	defer close(errors)

	for responseChan := range responseChannels {
		for response := range responseChan {

			//log.Debug("GOT RESPONSE: ", response.Type, response.Series)
			log.Debug("GOT RESPONSE: %v", 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 for %s", len(response.Series.Points), len(response.Series.Fields), response.Series.GetName())
				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
}

func NewStandardDeviationAggregator(q *parser.SelectQuery, v *parser.Value, defaultValue *parser.Value) (Aggregator, error) {
	if len(v.Elems) != 1 {
		return nil, common.NewQueryError(common.WrongNumberOfArguments, "function stddev() requires exactly one argument")
	}

	if v.Elems[0].Type == parser.ValueWildcard {
		return nil, common.NewQueryError(common.InvalidArgument, "function stddev() doesn't work with wildcards")
	}

	value, err := wrapDefaultValue(defaultValue)
	if err != nil {
		return nil, err
	}
	return &StandardDeviationAggregator{
		AbstractAggregator: AbstractAggregator{
			value: v.Elems[0],
		},
		defaultValue: value,
		alias:        v.Alias,
	}, nil
}