influxdb/query/influxql/response_iterator.go

362 lines
9.4 KiB
Go

package influxql
import (
"fmt"
"sort"
"strconv"
"time"
"github.com/influxdata/flux"
"github.com/influxdata/flux/execute"
"github.com/influxdata/flux/values"
)
// responseIterator implements flux.ResultIterator for a Response.
type responseIterator struct {
response *Response
resultIdx int
}
// NewresponseIterator constructs a responseIterator from a flux.ResultIterator.
func NewResponseIterator(r *Response) flux.ResultIterator {
return &responseIterator{
response: r,
}
}
// More returns true if there are results left to iterate through.
// It is used to implement flux.ResultIterator.
func (r *responseIterator) More() bool {
return r.resultIdx < len(r.response.Results)
}
// Next retrieves the next flux.Result.
// It is used to implement flux.ResultIterator.
func (r *responseIterator) Next() flux.Result {
res := r.response.Results[r.resultIdx]
r.resultIdx++
return newQueryResult(&res)
}
// Cancel is a noop.
// It is used to implement flux.ResultIterator.
func (r *responseIterator) Cancel() {}
// Err returns an error if the response contained an error.
// It is used to implement flux.ResultIterator.
func (r *responseIterator) Err() error {
if r.response.Err != "" {
return fmt.Errorf(r.response.Err)
}
return nil
}
// seriesIterator is a simple wrapper for Result that implements flux.Result and flux.TableIterator.
type seriesIterator struct {
result *Result
}
func newQueryResult(r *Result) *seriesIterator {
return &seriesIterator{
result: r,
}
}
// Name returns the results statement id.
// It is used to implement flux.Result.
func (r *seriesIterator) Name() string {
return strconv.Itoa(r.result.StatementID)
}
// Tables returns the original as a flux.TableIterator.
// It is used to implement flux.Result.
func (r *seriesIterator) Tables() flux.TableIterator {
return r
}
// Do iterates through the series of a Result.
// It is used to implement flux.TableIterator.
func (r *seriesIterator) Do(f func(flux.Table) error) error {
for _, row := range r.result.Series {
t, err := newQueryTable(row)
if err != nil {
return err
}
if err := f(t); err != nil {
return err
}
}
return nil
}
// queryTable implements flux.Table and flux.ColReader.
type queryTable struct {
row *Row
groupKey flux.GroupKey
colMeta []flux.ColMeta
cols []interface{}
}
func newQueryTable(r *Row) (*queryTable, error) {
t := &queryTable{
row: r,
}
if err := t.translateRowsToColumns(); err != nil {
return nil, err
}
return t, nil
}
// Data in a column is laid out in the following way:
// [ r.row.Columns... , r.tagKeys()... , r.row.Name ]
func (t *queryTable) translateRowsToColumns() error {
cols := t.Cols()
t.cols = make([]interface{}, len(cols))
for i, col := range cols {
switch col.Type {
case flux.TFloat:
t.cols[i] = make([]float64, 0, t.Len())
case flux.TInt:
t.cols[i] = make([]int64, 0, t.Len())
case flux.TUInt:
t.cols[i] = make([]uint64, 0, t.Len())
case flux.TString:
t.cols[i] = make([]string, 0, t.Len())
case flux.TBool:
t.cols[i] = make([]bool, 0, t.Len())
case flux.TTime:
t.cols[i] = make([]values.Time, 0, t.Len())
}
}
for _, els := range t.row.Values {
for i, el := range els {
col := cols[i]
switch col.Type {
case flux.TFloat:
val, ok := el.(float64)
if !ok {
return fmt.Errorf("unsupported type %T found in column %s of type %s", val, col.Label, col.Type)
}
t.cols[i] = append(t.cols[i].([]float64), val)
case flux.TInt:
val, ok := el.(int64)
if !ok {
return fmt.Errorf("unsupported type %T found in column %s of type %s", val, col.Label, col.Type)
}
t.cols[i] = append(t.cols[i].([]int64), val)
case flux.TUInt:
val, ok := el.(uint64)
if !ok {
return fmt.Errorf("unsupported type %T found in column %s of type %s", val, col.Label, col.Type)
}
t.cols[i] = append(t.cols[i].([]uint64), val)
case flux.TString:
val, ok := el.(string)
if !ok {
return fmt.Errorf("unsupported type %T found in column %s of type %s", val, col.Label, col.Type)
}
t.cols[i] = append(t.cols[i].([]string), val)
case flux.TBool:
val, ok := el.(bool)
if !ok {
return fmt.Errorf("unsupported type %T found in column %s of type %s", val, col.Label, col.Type)
}
t.cols[i] = append(t.cols[i].([]bool), val)
case flux.TTime:
switch val := el.(type) {
case int64:
t.cols[i] = append(t.cols[i].([]values.Time), values.Time(val))
case float64:
t.cols[i] = append(t.cols[i].([]values.Time), values.Time(val))
case string:
tm, err := time.Parse(time.RFC3339, val)
if err != nil {
return fmt.Errorf("could not parse string %q as time: %v", val, err)
}
t.cols[i] = append(t.cols[i].([]values.Time), values.ConvertTime(tm))
default:
return fmt.Errorf("unsupported type %T found in column %s", val, col.Label)
}
default:
return fmt.Errorf("invalid type %T found in column %s", el, col.Label)
}
}
j := len(t.row.Columns)
for j < len(t.row.Columns)+len(t.row.Tags) {
col := cols[j]
t.cols[j] = append(t.cols[j].([]string), t.row.Tags[col.Label])
j++
}
t.cols[j] = append(t.cols[j].([]string), t.row.Name)
}
return nil
}
// Key constructs the flux.GroupKey for a Row from the rows
// tags and measurement.
// It is used to implement flux.Table and flux.ColReader.
func (r *queryTable) Key() flux.GroupKey {
if r.groupKey == nil {
cols := make([]flux.ColMeta, len(r.row.Tags)+1) // plus one is for measurement
vs := make([]values.Value, len(r.row.Tags)+1)
kvs := make([]interface{}, len(r.row.Tags)+1)
colMeta := r.Cols()
labels := append(r.tagKeys(), "_measurement")
for j, label := range labels {
idx := execute.ColIdx(label, colMeta)
if idx < 0 {
panic(fmt.Errorf("table invalid: missing group column %q", label))
}
cols[j] = colMeta[idx]
kvs[j] = "string"
v, err := values.NewValue(kvs[j], execute.ConvertToKind(cols[j].Type))
if err != nil {
panic(err)
}
vs[j] = v
}
r.groupKey = execute.NewGroupKey(cols, vs)
}
return r.groupKey
}
// tags returns the tag keys for a Row.
func (r *queryTable) tagKeys() []string {
tags := []string{}
for t := range r.row.Tags {
tags = append(tags, t)
}
sort.Strings(tags)
return tags
}
// Cols returns the columns for a row where the data is laid out in the following way:
// [ r.row.Columns... , r.tagKeys()... , r.row.Name ]
// It is used to implement flux.Table and flux.ColReader.
func (r *queryTable) Cols() []flux.ColMeta {
if r.colMeta == nil {
colMeta := make([]flux.ColMeta, len(r.row.Columns)+len(r.row.Tags)+1)
for i, col := range r.row.Columns {
colMeta[i] = flux.ColMeta{
Label: col,
Type: flux.TInvalid,
}
if col == "time" {
// rename the time column
colMeta[i].Label = "_time"
colMeta[i].Type = flux.TTime
}
}
if len(r.row.Values) < 1 {
panic("must have at least one value")
}
data := r.row.Values[0]
for i := range r.row.Columns {
v := data[i]
if colMeta[i].Label == "_time" {
continue
}
switch v.(type) {
case float64:
colMeta[i].Type = flux.TFloat
case int64:
colMeta[i].Type = flux.TInt
case uint64:
colMeta[i].Type = flux.TUInt
case bool:
colMeta[i].Type = flux.TBool
case string:
colMeta[i].Type = flux.TString
}
}
tags := r.tagKeys()
leng := len(r.row.Columns)
for i, tag := range tags {
colMeta[leng+i] = flux.ColMeta{
Label: tag,
Type: flux.TString,
}
}
leng = leng + len(tags)
colMeta[leng] = flux.ColMeta{
Label: "_measurement",
Type: flux.TString,
}
r.colMeta = colMeta
}
return r.colMeta
}
// Do applies f to itself. This is because Row is a flux.ColReader.
// It is used to implement flux.Table.
func (r *queryTable) Do(f func(flux.ColReader) error) error {
return f(r)
}
// RefCount is a noop.
// It is used to implement flux.ColReader.
func (r *queryTable) RefCount(n int) {}
// Empty returns true if a Row has no values.
// It is used to implement flux.Table.
func (r *queryTable) Empty() bool { return r.Len() == 0 }
// Len returns the length or r.row.Values
// It is used to implement flux.ColReader.
func (r *queryTable) Len() int {
return len(r.row.Values)
}
// Bools returns the values in column index j as bools.
// It will panic if the column is not a []bool.
// It is used to implement flux.ColReader.
func (r *queryTable) Bools(j int) []bool {
return r.cols[j].([]bool)
}
// Ints returns the values in column index j as ints.
// It will panic if the column is not a []int64.
// It is used to implement flux.ColReader.
func (r *queryTable) Ints(j int) []int64 {
return r.cols[j].([]int64)
}
// UInts returns the values in column index j as ints.
// It will panic if the column is not a []uint64.
// It is used to implement flux.ColReader.
func (r *queryTable) UInts(j int) []uint64 {
return r.cols[j].([]uint64)
}
// Floats returns the values in column index j as floats.
// It will panic if the column is not a []float64.
// It is used to implement flux.ColReader.
func (r *queryTable) Floats(j int) []float64 {
return r.cols[j].([]float64)
}
// Strings returns the values in column index j as strings.
// It will panic if the column is not a []string.
// It is used to implement flux.ColReader.
func (r *queryTable) Strings(j int) []string {
return r.cols[j].([]string)
}
// Times returns the values in column index j as values.Times.
// It will panic if the column is not a []values.Time.
// It is used to implement flux.ColReader.
func (r *queryTable) Times(j int) []values.Time {
return r.cols[j].([]values.Time)
}