time_series.go

package search

import (
	"encoding/json"
	"net/http"
	"reflect"
	"strings"
	"time"

	"gitlab.com/uafrica/go-utils/errors"
	"gitlab.com/uafrica/go-utils/logger"
)

type TimeSeries interface {
	Write(StartTime time.Time, EndTime time.Time, data interface{}) error
}

type timeSeries struct {
	w         *writer
	indexName string
	dataType  reflect.Type
	fields    []dataField
}

type dataField struct {
	name    string
	index   []int
	mapping MappingProperty
}

//create a time series to write e.g. api logs
//the tmpl must be your log data struct consisting of public fields as:
//	Xxx string `json:"<name>" search:"keyword|text|long|date"`	(can later add more types)
//	Xxx time.Time `json:"<name>"`								assumes type "date" for opensearch
//	Xxx int `json:"<name>"`										assumes type "long" for opensearch, specify keyword if required
func (w *writer) TimeSeries(indexName string, tmpl interface{}) (TimeSeries, error) {
	if !indexNameRegex.MatchString(indexName) {
		return nil, errors.Errorf("invalid index_name:\"%s\"", indexName)
	}
	structType := reflect.TypeOf(tmpl)
	if tmpl == nil || structType.Kind() != reflect.Struct {
		return nil, errors.Errorf("%T is not a struct", tmpl)
	}

	ts := &timeSeries{
		w:         w,
		indexName: indexName,
		dataType:  structType,
		fields:    []dataField{},
	}

	//define the OpenSearch index mapping
	indexSpec := Index{
		Settings: Settings{
			Index: &SettingsIndex{
				NumberOfShards:   4,
				NumberOfReplicas: 0,
			},
		},
		Mappings: Mappings{
			Properties: map[string]MappingProperty{},
		},
	}
	for i := 0; i < structType.NumField(); i++ {
		structField := structType.Field(i)
		dataField := dataField{
			name:    structField.Name,
			index:   structField.Index,
			mapping: MappingProperty{Type: "text"},
		}