示例#1
0
func (self *Shard) Query(querySpec *parser.QuerySpec, processor cluster.QueryProcessor) error {
	if querySpec.IsListSeriesQuery() {
		return self.executeListSeriesQuery(querySpec, processor)
	} else if querySpec.IsDeleteFromSeriesQuery() {
		return self.executeDeleteQuery(querySpec, processor)
	}

	seriesAndColumns := querySpec.SelectQuery().GetReferencedColumns()

	if !self.hasReadAccess(querySpec) {
		return errors.New("User does not have access to one or more of the series requested.")
	}

	for series, columns := range seriesAndColumns {
		if regex, ok := series.GetCompiledRegex(); ok {
			seriesNames := self.metaStore.GetSeriesForDatabaseAndRegex(querySpec.Database(), regex)
			for _, name := range seriesNames {
				if !querySpec.HasReadAccess(name) {
					continue
				}
				err := self.executeQueryForSeries(querySpec, name, columns, processor)
				if err != nil {
					return err
				}
			}
		} else {
			err := self.executeQueryForSeries(querySpec, series.Name, columns, processor)
			if err != nil {
				return err
			}
		}
	}
	return nil
}
示例#2
0
func (self *Shard) Query(querySpec *parser.QuerySpec, processor engine.Processor) error {
	self.closeLock.RLock()
	defer self.closeLock.RUnlock()
	if self.closed {
		return fmt.Errorf("Shard is closed")
	}
	if querySpec.IsListSeriesQuery() {
		return fmt.Errorf("List series queries should never come to the shard")
	} else if querySpec.IsDeleteFromSeriesQuery() {
		return self.executeDeleteQuery(querySpec, processor)
	}

	if !self.hasReadAccess(querySpec) {
		return errors.New("User does not have access to one or more of the series requested.")
	}

	switch t := querySpec.SelectQuery().FromClause.Type; t {
	case parser.FromClauseArray:
		log.Debug("Shard %s: running a regular query", self.db.Path())
		return self.executeArrayQuery(querySpec, processor)
	case parser.FromClauseMerge, parser.FromClauseInnerJoin:
		log.Debug("Shard %s: running a merge query", self.db.Path())
		return self.executeMergeQuery(querySpec, processor, t)
	default:
		panic(fmt.Errorf("Unknown from clause type %s", t))
	}
}
示例#3
0
func (self *ShardData) Query(querySpec *parser.QuerySpec, response chan *p.Response) {
	log.Debug("QUERY: shard %d, query '%s'", self.Id(), querySpec.GetQueryString())
	defer common.RecoverFunc(querySpec.Database(), querySpec.GetQueryString(), func(err interface{}) {
		response <- &p.Response{Type: &endStreamResponse, ErrorMessage: p.String(fmt.Sprintf("%s", err))}
	})

	// This is only for queries that are deletes or drops. They need to be sent everywhere as opposed to just the local or one of the remote shards.
	// But this boolean should only be set to true on the server that receives the initial query.
	if querySpec.RunAgainstAllServersInShard {
		if querySpec.IsDeleteFromSeriesQuery() {
			self.logAndHandleDeleteQuery(querySpec, response)
		} else if querySpec.IsDropSeriesQuery() {
			self.logAndHandleDropSeriesQuery(querySpec, response)
		}
	}

	if self.IsLocal {
		var processor QueryProcessor
		var err error

		if querySpec.IsListSeriesQuery() {
			processor = engine.NewListSeriesEngine(response)
		} else if querySpec.IsDeleteFromSeriesQuery() || querySpec.IsDropSeriesQuery() || querySpec.IsSinglePointQuery() {
			maxDeleteResults := 10000
			processor = engine.NewPassthroughEngine(response, maxDeleteResults)
		} else {
			query := querySpec.SelectQuery()
			if self.ShouldAggregateLocally(querySpec) {
				log.Debug("creating a query engine")
				processor, err = engine.NewQueryEngine(query, response)
				if err != nil {
					response <- &p.Response{Type: &endStreamResponse, ErrorMessage: p.String(err.Error())}
					log.Error("Error while creating engine: %s", err)
					return
				}
				processor.SetShardInfo(int(self.Id()), self.IsLocal)
			} else if query.HasAggregates() {
				maxPointsToBufferBeforeSending := 1000
				log.Debug("creating a passthrough engine")
				processor = engine.NewPassthroughEngine(response, maxPointsToBufferBeforeSending)
			} else {
				maxPointsToBufferBeforeSending := 1000
				log.Debug("creating a passthrough engine with limit")
				processor = engine.NewPassthroughEngineWithLimit(response, maxPointsToBufferBeforeSending, query.Limit)
			}

			if query.GetFromClause().Type != parser.FromClauseInnerJoin {
				// Joins do their own filtering since we need to get all
				// points before filtering. This is due to the fact that some
				// where expressions will be difficult to compute before the
				// points are joined together, think where clause with
				// left.column = 'something' or right.column =
				// 'something_else'. We can't filter the individual series
				// separately. The filtering happens in merge.go:55

				processor = engine.NewFilteringEngine(query, processor)
			}
		}
		shard, err := self.store.GetOrCreateShard(self.id)
		if err != nil {
			response <- &p.Response{Type: &endStreamResponse, ErrorMessage: p.String(err.Error())}
			log.Error("Error while getting shards: %s", err)
			return
		}
		defer self.store.ReturnShard(self.id)
		err = shard.Query(querySpec, processor)
		// if we call Close() in case of an error it will mask the error
		if err != nil {
			response <- &p.Response{Type: &endStreamResponse, ErrorMessage: p.String(err.Error())}
			return
		}
		processor.Close()
		response <- &p.Response{Type: &endStreamResponse}
		return
	}

	if server := self.randomHealthyServer(); server != nil {
		log.Debug("Querying server %d for shard %d", server.GetId(), self.Id())
		request := self.createRequest(querySpec)
		server.MakeRequest(request, response)
		return
	}

	message := fmt.Sprintf("No servers up to query shard %d", self.id)
	response <- &p.Response{Type: &endStreamResponse, ErrorMessage: &message}
	log.Error(message)
}