// iteratorCreator returns a new instance of IteratorCreator based on stmt.
func (e *QueryExecutor) iteratorCreator(stmt *influxql.SelectStatement, opt *influxql.SelectOptions) (influxql.IteratorCreator, error) {
// Retrieve a list of shard IDs.
shards, err := e.MetaClient.ShardsByTimeRange(stmt.Sources, opt.MinTime, opt.MaxTime)
if err != nil {
return nil, err
}
// Generate iterators for each node.
ics := make([]influxql.IteratorCreator, 0)
if err := func() error {
for _, shard := range shards {
ic := e.TSDBStore.ShardIteratorCreator(shard.ID)
if ic == nil {
continue
}
ics = append(ics, ic)
}
return nil
}(); err != nil {
influxql.IteratorCreators(ics).Close()
return nil, err
}
return influxql.IteratorCreators(ics), nil
}
func (s *Store) IteratorCreator(shards []uint64) (influxql.IteratorCreator, error) {
// Generate iterators for each node.
ics := make([]influxql.IteratorCreator, 0)
if err := func() error {
for _, id := range shards {
ic := s.ShardIteratorCreator(id)
if ic == nil {
continue
}
ics = append(ics, ic)
}
return nil
}(); err != nil {
influxql.IteratorCreators(ics).Close()
return nil, err
}
return influxql.IteratorCreators(ics), nil
}
func (s *TSDBStore) IteratorCreator(shards []meta.ShardInfo, opt *influxql.SelectOptions) (influxql.IteratorCreator, error) {
// Generate iterators for each node.
ics := make([]influxql.IteratorCreator, 0)
if err := func() error {
for _, shard := range shards {
ic := s.ShardIteratorCreator(shard.ID)
if ic == nil {
continue
}
ics = append(ics, ic)
}
return nil
}(); err != nil {
influxql.IteratorCreators(ics).Close()
return nil, err
}
return influxql.IteratorCreators(ics), nil
}
func (s *Service) processCreateIteratorRequest(conn net.Conn) {
defer conn.Close()
var itr influxql.Iterator
if err := func() error {
// Parse request.
var req CreateIteratorRequest
if err := DecodeLV(conn, &req); err != nil {
return err
}
// Collect iterator creators for each shard.
ics := make([]influxql.IteratorCreator, 0, len(req.ShardIDs))
for _, shardID := range req.ShardIDs {
ic := s.TSDBStore.ShardIteratorCreator(shardID)
if ic == nil {
return nil
}
ics = append(ics, ic)
}
// Generate a single iterator from all shards.
i, err := influxql.IteratorCreators(ics).CreateIterator(req.Opt)
if err != nil {
return err
}
itr = i
return nil
}(); err != nil {
itr.Close()
s.Logger.Printf("error reading CreateIterator request: %s", err)
EncodeTLV(conn, createIteratorResponseMessage, &CreateIteratorResponse{Err: err})
return
}
// Encode success response.
if err := EncodeTLV(conn, createIteratorResponseMessage, &CreateIteratorResponse{}); err != nil {
s.Logger.Printf("error writing CreateIterator response: %s", err)
return
}
// Exit if no iterator was produced.
if itr == nil {
return
}
// Stream iterator to connection.
if err := influxql.NewIteratorEncoder(conn).EncodeIterator(itr); err != nil {
s.Logger.Printf("error encoding CreateIterator iterator: %s", err)
return
}
}
func (s *Service) processFieldDimensionsRequest(conn net.Conn) {
var fields, dimensions map[string]struct{}
if err := func() error {
// Parse request.
var req FieldDimensionsRequest
if err := DecodeLV(conn, &req); err != nil {
return err
}
sh, ok := s.TSDBStore.(ShardIteratorCreator)
if !ok {
return errors.New("unable to access a specific shard with this tsdb store")
}
// Collect iterator creators for each shard.
ics := make([]influxql.IteratorCreator, 0, len(req.ShardIDs))
for _, shardID := range req.ShardIDs {
ic := sh.ShardIteratorCreator(shardID)
if ic == nil {
return nil
}
ics = append(ics, ic)
}
// Generate a single iterator from all shards.
f, d, err := influxql.IteratorCreators(ics).FieldDimensions(req.Sources)
if err != nil {
return err
}
fields, dimensions = f, d
return nil
}(); err != nil {
s.Logger.Printf("error reading FieldDimensions request: %s", err)
EncodeTLV(conn, fieldDimensionsResponseMessage, &FieldDimensionsResponse{Err: err})
return
}
// Encode success response.
if err := EncodeTLV(conn, fieldDimensionsResponseMessage, &FieldDimensionsResponse{
Fields: fields,
Dimensions: dimensions,
}); err != nil {
s.Logger.Printf("error writing FieldDimensions response: %s", err)
return
}
}
func (s *Service) processSeriesKeysRequest(conn net.Conn) {
var seriesList influxql.SeriesList
if err := func() error {
// Parse request.
var req SeriesKeysRequest
if err := DecodeLV(conn, &req); err != nil {
return err
}
sh, ok := s.TSDBStore.(ShardIteratorCreator)
if !ok {
return errors.New("unable to access a specific shard with this tsdb store")
}
// Collect iterator creators for each shard.
ics := make([]influxql.IteratorCreator, 0, len(req.ShardIDs))
for _, shardID := range req.ShardIDs {
ic := sh.ShardIteratorCreator(shardID)
if ic == nil {
return nil
}
ics = append(ics, ic)
}
// Generate a single iterator from all shards.
a, err := influxql.IteratorCreators(ics).SeriesKeys(req.Opt)
if err != nil {
return err
}
seriesList = a
return nil
}(); err != nil {
s.Logger.Printf("error reading SeriesKeys request: %s", err)
EncodeTLV(conn, seriesKeysResponseMessage, &SeriesKeysResponse{Err: err})
return
}
// Encode success response.
if err := EncodeTLV(conn, seriesKeysResponseMessage, &SeriesKeysResponse{
SeriesList: seriesList,
}); err != nil {
s.Logger.Printf("error writing SeriesKeys response: %s", err)
return
}
}
func (s *Service) processCreateIteratorRequest(conn net.Conn) {
defer conn.Close()
var itr influxql.Iterator
if err := func() error {
// Parse request.
var req CreateIteratorRequest
if err := DecodeLV(conn, &req); err != nil {
return err
}
sh, ok := s.TSDBStore.(ShardIteratorCreator)
if !ok {
return errors.New("unable to access a specific shard with this tsdb store")
}
// Collect iterator creators for each shard.
ics := make([]influxql.IteratorCreator, 0, len(req.ShardIDs))
for _, shardID := range req.ShardIDs {
ic := sh.ShardIteratorCreator(shardID)
if ic == nil {
continue
}
ics = append(ics, ic)
}
// Return immediately if there are no iterator creators.
if len(ics) == 0 {
return nil
}
// Generate a single iterator from all shards.
i, err := influxql.IteratorCreators(ics).CreateIterator(req.Opt)
if err != nil {
return err
}
itr = i
return nil
}(); err != nil {
s.Logger.Printf("error reading CreateIterator request: %s", err)
EncodeTLV(conn, createIteratorResponseMessage, &CreateIteratorResponse{Err: err})
return
}
resp := CreateIteratorResponse{}
if itr != nil {
switch itr.(type) {
case influxql.FloatIterator:
resp.Type = influxql.Float
case influxql.IntegerIterator:
resp.Type = influxql.Integer
case influxql.StringIterator:
resp.Type = influxql.String
case influxql.BooleanIterator:
resp.Type = influxql.Boolean
}
resp.Stats = itr.Stats()
}
// Encode success response.
if err := EncodeTLV(conn, createIteratorResponseMessage, &resp); err != nil {
s.Logger.Printf("error writing CreateIterator response: %s", err)
return
}
// Exit if no iterator was produced.
if itr == nil {
return
}
// Stream iterator to connection.
if err := influxql.NewIteratorEncoder(conn).EncodeIterator(itr); err != nil {
s.Logger.Printf("error encoding CreateIterator iterator: %s", err)
return
}
}
// iteratorCreator returns a new instance of IteratorCreator based on stmt.
func (e *QueryExecutor) iteratorCreator(stmt *influxql.SelectStatement, opt *influxql.SelectOptions) (influxql.IteratorCreator, error) {
// Retrieve a list of shard IDs.
shards, err := e.MetaClient.ShardsByTimeRange(stmt.Sources, opt.MinTime, opt.MaxTime)
if err != nil {
return nil, err
}
// Map shards to nodes.
shardIDsByNodeID := make(map[uint64][]uint64)
for _, si := range shards {
// Always assign to local node if it has the shard.
// Otherwise randomly select a remote node.
var nodeID uint64
if si.OwnedBy(e.Node.ID) {
nodeID = e.Node.ID
} else if len(si.Owners) > 0 {
nodeID = si.Owners[rand.Intn(len(si.Owners))].NodeID
} else {
// This should not occur but if the shard has no owners then
// we don't want this to panic by trying to randomly select a node.
continue
}
// Otherwise assign it to a remote shard randomly.
shardIDsByNodeID[nodeID] = append(shardIDsByNodeID[nodeID], si.ID)
}
// Generate iterators for each node.
ics := make([]influxql.IteratorCreator, 0)
if err := func() error {
for nodeID, shardIDs := range shardIDsByNodeID {
// Sort shard IDs so we get more predicable execution.
sort.Sort(uint64Slice(shardIDs))
// Create iterator creators from TSDB if local.
if nodeID == e.Node.ID {
for _, shardID := range shardIDs {
ic := e.TSDBStore.ShardIteratorCreator(shardID)
if ic == nil {
continue
}
ics = append(ics, ic)
}
continue
}
// Otherwise create iterator creator remotely.
dialer := &NodeDialer{
MetaClient: e.MetaClient,
Timeout: e.Timeout,
}
ics = append(ics, newRemoteIteratorCreator(dialer, nodeID, shardIDs))
}
return nil
}(); err != nil {
influxql.IteratorCreators(ics).Close()
return nil, err
}
return influxql.IteratorCreators(ics), nil
}