influxdb/tsdb/cursors/cursor.go

78 lines
1.4 KiB
Go

package cursors
import (
"context"
"github.com/influxdata/influxdb/models"
)
const DefaultMaxPointsPerBlock = 1000
type Cursor interface {
Close()
Err() error
Stats() CursorStats
}
type IntegerArrayCursor interface {
Cursor
Next() *IntegerArray
}
type FloatArrayCursor interface {
Cursor
Next() *FloatArray
}
type UnsignedArrayCursor interface {
Cursor
Next() *UnsignedArray
}
type StringArrayCursor interface {
Cursor
Next() *StringArray
}
type BooleanArrayCursor interface {
Cursor
Next() *BooleanArray
}
type CursorRequest struct {
Name []byte
Tags models.Tags
Field string
Ascending bool
StartTime int64
EndTime int64
}
type CursorIterator interface {
Next(ctx context.Context, r *CursorRequest) (Cursor, error)
Stats() CursorStats
}
type CursorIterators []CursorIterator
// Stats returns the aggregate stats of all cursor iterators.
func (a CursorIterators) Stats() CursorStats {
var stats CursorStats
for _, itr := range a {
stats.Add(itr.Stats())
}
return stats
}
// CursorStats represents stats collected by a cursor.
type CursorStats struct {
ScannedValues int // number of values scanned
ScannedBytes int // number of uncompressed bytes scanned
}
// Add adds other to s and updates s.
func (s *CursorStats) Add(other CursorStats) {
s.ScannedValues += other.ScannedValues
s.ScannedBytes += other.ScannedBytes
}