grafana/pkg/expr/ml/node.go

66 lines
2.1 KiB
Go

package ml
import (
"fmt"
"strings"
"time"
"github.com/grafana/grafana-plugin-sdk-go/backend"
jsoniter "github.com/json-iterator/go"
"github.com/grafana/grafana/pkg/api/response"
)
var json = jsoniter.ConfigCompatibleWithStandardLibrary
type CommandType string
const (
Outlier CommandType = "outlier"
// format of the time used by outlier API
timeFormat = "2006-01-02T15:04:05.999999999"
defaultInterval = 1000 * time.Millisecond
)
// Command is an interface implemented by all Machine Learning commands that can be executed against ML API.
type Command interface {
// DatasourceUID returns UID of a data source that is used by machine learning as the source of data
DatasourceUID() string
// Execute creates a payload send request to the ML API by calling the function argument sendRequest, and then parses response.
// Function sendRequest is supposed to abstract the client configuration such creating http request, adding authorization parameters, host etc.
Execute(from, to time.Time, sendRequest func(method string, path string, payload []byte) (response.Response, error)) (*backend.QueryDataResponse, error)
Type() string
}
// UnmarshalCommand parses a config parameters and creates a command. Requires key `type` to be specified.
// Based on the value of `type` field it parses a Command
func UnmarshalCommand(query []byte, appURL string) (Command, error) {
var expr CommandConfiguration
err := json.Unmarshal(query, &expr)
if err != nil {
return nil, fmt.Errorf("failed to unmarshal Machine learning command: %w", err)
}
if len(expr.Type) == 0 {
return nil, fmt.Errorf("required field 'type' is not specified or empty. Should be one of [%s]", Outlier)
}
if len(expr.Config) == 0 {
return nil, fmt.Errorf("required field 'config' is not specified")
}
var cmd Command
switch mlType := strings.ToLower(expr.Type); mlType {
case string(Outlier):
cmd, err = unmarshalOutlierCommand(expr, appURL)
default:
return nil, fmt.Errorf("unsupported command type. Should be one of [%s]", Outlier)
}
if err != nil {
return nil, fmt.Errorf("failed to unmarshal Machine learning %s command: %w", expr.Type, err)
}
return cmd, nil
}