grafana/pkg/expr/nodes.go
Ikko Ashimine 202f295e51
Chore: Fix typo in nodes.go (#38636)
commmon -> common
2021-08-27 14:57:41 +02:00

378 lines
9.7 KiB
Go

package expr
import (
"context"
"encoding/json"
"fmt"
"time"
"github.com/grafana/grafana-plugin-sdk-go/backend"
"github.com/grafana/grafana-plugin-sdk-go/data"
"github.com/grafana/grafana/pkg/expr/classic"
"github.com/grafana/grafana/pkg/expr/mathexp"
"github.com/grafana/grafana/pkg/infra/log"
"gonum.org/v1/gonum/graph/simple"
)
var (
logger = log.New("expr")
)
// baseNode includes common properties used across DPNodes.
type baseNode struct {
id int64
refID string
}
type rawNode struct {
RefID string `json:"refId"`
Query map[string]interface{}
QueryType string
TimeRange TimeRange
DatasourceUID string
}
func (rn *rawNode) GetDatasourceName() (string, error) {
rawDs, ok := rn.Query["datasource"]
if !ok {
return "", nil
}
dsName, ok := rawDs.(string)
if !ok {
return "", fmt.Errorf("expted datasource identifier to be a string, got %T", rawDs)
}
return dsName, nil
}
func (rn *rawNode) GetCommandType() (c CommandType, err error) {
rawType, ok := rn.Query["type"]
if !ok {
return c, fmt.Errorf("no expression command type in query for refId %v", rn.RefID)
}
typeString, ok := rawType.(string)
if !ok {
return c, fmt.Errorf("expected expression command type to be a string, got type %T", rawType)
}
return ParseCommandType(typeString)
}
// String returns a string representation of the node. In particular for
// %v formatting in error messages.
func (b *baseNode) String() string {
return b.refID
}
// CMDNode is a DPNode that holds an expression command.
type CMDNode struct {
baseNode
CMDType CommandType
Command Command
}
// ID returns the id of the node so it can fulfill the gonum's graph Node interface.
func (b *baseNode) ID() int64 {
return b.id
}
// RefID returns the refId of the node.
func (b *baseNode) RefID() string {
return b.refID
}
// NodeType returns the data pipeline node type.
func (gn *CMDNode) NodeType() NodeType {
return TypeCMDNode
}
// Execute runs the node and adds the results to vars. If the node requires
// other nodes they must have already been executed and their results must
// already by in vars.
func (gn *CMDNode) Execute(ctx context.Context, vars mathexp.Vars, s *Service) (mathexp.Results, error) {
return gn.Command.Execute(ctx, vars)
}
func buildCMDNode(dp *simple.DirectedGraph, rn *rawNode) (*CMDNode, error) {
commandType, err := rn.GetCommandType()
if err != nil {
return nil, fmt.Errorf("invalid expression command type in '%v'", rn.RefID)
}
node := &CMDNode{
baseNode: baseNode{
id: dp.NewNode().ID(),
refID: rn.RefID,
},
CMDType: commandType,
}
switch commandType {
case TypeMath:
node.Command, err = UnmarshalMathCommand(rn)
case TypeReduce:
node.Command, err = UnmarshalReduceCommand(rn)
case TypeResample:
node.Command, err = UnmarshalResampleCommand(rn)
case TypeClassicConditions:
node.Command, err = classic.UnmarshalConditionsCmd(rn.Query, rn.RefID)
default:
return nil, fmt.Errorf("expression command type '%v' in '%v' not implemented", commandType, rn.RefID)
}
if err != nil {
return nil, err
}
return node, nil
}
const (
defaultIntervalMS = int64(64)
defaultMaxDP = int64(5000)
)
// DSNode is a DPNode that holds a datasource request.
type DSNode struct {
baseNode
query json.RawMessage
datasourceID int64
datasourceUID string
orgID int64
queryType string
timeRange TimeRange
intervalMS int64
maxDP int64
request Request
}
// NodeType returns the data pipeline node type.
func (dn *DSNode) NodeType() NodeType {
return TypeDatasourceNode
}
func (s *Service) buildDSNode(dp *simple.DirectedGraph, rn *rawNode, req *Request) (*DSNode, error) {
encodedQuery, err := json.Marshal(rn.Query)
if err != nil {
return nil, err
}
dsNode := &DSNode{
baseNode: baseNode{
id: dp.NewNode().ID(),
refID: rn.RefID,
},
orgID: req.OrgId,
query: json.RawMessage(encodedQuery),
queryType: rn.QueryType,
intervalMS: defaultIntervalMS,
maxDP: defaultMaxDP,
timeRange: rn.TimeRange,
request: *req,
}
rawDsID, ok := rn.Query["datasourceId"]
switch ok {
case true:
floatDsID, ok := rawDsID.(float64)
if !ok {
return nil, fmt.Errorf("expected datasourceId to be a float64, got type %T for refId %v", rawDsID, rn.RefID)
}
dsNode.datasourceID = int64(floatDsID)
default:
if rn.DatasourceUID == "" {
return nil, fmt.Errorf("neither datasourceId or datasourceUid in expression data source request for refId %v", rn.RefID)
}
dsNode.datasourceUID = rn.DatasourceUID
}
var floatIntervalMS float64
if rawIntervalMS, ok := rn.Query["intervalMs"]; ok {
if floatIntervalMS, ok = rawIntervalMS.(float64); !ok {
return nil, fmt.Errorf("expected intervalMs to be an float64, got type %T for refId %v", rawIntervalMS, rn.RefID)
}
dsNode.intervalMS = int64(floatIntervalMS)
}
var floatMaxDP float64
if rawMaxDP, ok := rn.Query["maxDataPoints"]; ok {
if floatMaxDP, ok = rawMaxDP.(float64); !ok {
return nil, fmt.Errorf("expected maxDataPoints to be an float64, got type %T for refId %v", rawMaxDP, rn.RefID)
}
dsNode.maxDP = int64(floatMaxDP)
}
return dsNode, nil
}
// Execute runs the node and adds the results to vars. If the node requires
// other nodes they must have already been executed and their results must
// already by in vars.
func (dn *DSNode) Execute(ctx context.Context, vars mathexp.Vars, s *Service) (mathexp.Results, error) {
pc := backend.PluginContext{
OrgID: dn.orgID,
DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{
ID: dn.datasourceID,
UID: dn.datasourceUID,
},
}
q := []backend.DataQuery{
{
RefID: dn.refID,
MaxDataPoints: dn.maxDP,
Interval: time.Duration(int64(time.Millisecond) * dn.intervalMS),
JSON: dn.query,
TimeRange: backend.TimeRange{
From: dn.timeRange.From,
To: dn.timeRange.To,
},
QueryType: dn.queryType,
},
}
resp, err := s.queryData(ctx, &backend.QueryDataRequest{
PluginContext: pc,
Queries: q,
Headers: dn.request.Headers,
})
if err != nil {
return mathexp.Results{}, err
}
vals := make([]mathexp.Value, 0)
for refID, qr := range resp.Responses {
if qr.Error != nil {
return mathexp.Results{}, fmt.Errorf("failed to execute query %v: %w", refID, qr.Error)
}
if len(qr.Frames) == 1 {
frame := qr.Frames[0]
if frame.TimeSeriesSchema().Type == data.TimeSeriesTypeNot && isNumberTable(frame) {
logger.Debug("expression datasource query (numberSet)", "query", refID)
numberSet, err := extractNumberSet(frame)
if err != nil {
return mathexp.Results{}, err
}
for _, n := range numberSet {
vals = append(vals, n)
}
return mathexp.Results{
Values: vals,
}, nil
}
}
for _, frame := range qr.Frames {
logger.Debug("expression datasource query (seriesSet)", "query", refID)
series, err := WideToMany(frame)
if err != nil {
return mathexp.Results{}, err
}
for _, s := range series {
vals = append(vals, s)
}
}
}
return mathexp.Results{
Values: vals,
}, nil
}
func isNumberTable(frame *data.Frame) bool {
if frame == nil || frame.Fields == nil {
return false
}
numericCount := 0
stringCount := 0
otherCount := 0
for _, field := range frame.Fields {
fType := field.Type()
switch {
case fType.Numeric():
numericCount++
case fType == data.FieldTypeString || fType == data.FieldTypeNullableString:
stringCount++
default:
otherCount++
}
}
return numericCount == 1 && otherCount == 0
}
func extractNumberSet(frame *data.Frame) ([]mathexp.Number, error) {
numericField := 0
stringFieldIdxs := []int{}
stringFieldNames := []string{}
for i, field := range frame.Fields {
fType := field.Type()
switch {
case fType.Numeric():
numericField = i
case fType == data.FieldTypeString || fType == data.FieldTypeNullableString:
stringFieldIdxs = append(stringFieldIdxs, i)
stringFieldNames = append(stringFieldNames, field.Name)
}
}
numbers := make([]mathexp.Number, frame.Rows())
for rowIdx := 0; rowIdx < frame.Rows(); rowIdx++ {
val, _ := frame.FloatAt(numericField, rowIdx)
var labels data.Labels
for i := 0; i < len(stringFieldIdxs); i++ {
if i == 0 {
labels = make(data.Labels)
}
key := stringFieldNames[i] // TODO check for duplicate string column names
val, _ := frame.ConcreteAt(stringFieldIdxs[i], rowIdx)
labels[key] = val.(string) // TODO check assertion / return error
}
n := mathexp.NewNumber("", labels)
n.SetValue(&val)
numbers[rowIdx] = n
}
return numbers, nil
}
// WideToMany converts a data package wide type Frame to one or multiple Series. A series
// is created for each value type column of wide frame.
//
// This might not be a good idea long term, but works now as an adapter/shim.
func WideToMany(frame *data.Frame) ([]mathexp.Series, error) {
tsSchema := frame.TimeSeriesSchema()
if tsSchema.Type != data.TimeSeriesTypeWide {
return nil, fmt.Errorf("input data must be a wide series but got type %s (input refid)", tsSchema.Type)
}
if len(tsSchema.ValueIndices) == 1 {
s, err := mathexp.SeriesFromFrame(frame)
if err != nil {
return nil, err
}
return []mathexp.Series{s}, nil
}
series := []mathexp.Series{}
for _, valIdx := range tsSchema.ValueIndices {
l := frame.Rows()
f := data.NewFrameOfFieldTypes(frame.Name, l, frame.Fields[tsSchema.TimeIndex].Type(), frame.Fields[valIdx].Type())
f.Fields[0].Name = frame.Fields[tsSchema.TimeIndex].Name
f.Fields[1].Name = frame.Fields[valIdx].Name
if frame.Fields[valIdx].Labels != nil {
f.Fields[1].Labels = frame.Fields[valIdx].Labels.Copy()
}
for i := 0; i < l; i++ {
f.SetRow(i, frame.Fields[tsSchema.TimeIndex].CopyAt(i), frame.Fields[valIdx].CopyAt(i))
}
s, err := mathexp.SeriesFromFrame(f)
if err != nil {
return nil, err
}
series = append(series, s)
}
return series, nil
}