blog_backend_api/db/elasticEngine.go

package db

import (
	"background/utils"
	"encoding/json"
	"reflect"

	"github.com/pkg/errors"
	"golang.org/x/net/context"
	"gopkg.in/olivere/elastic.v7"
	"qiniupkg.com/x/log.v7"
)
const(
	ERROR_PTR = "null pointer error"
	INPUT_TYPE_ERROR = "wrong input parameter"
	CREATED_ERROR = "create error"
	DELETE_ERROR = "delete error"
	INDEX_EXISTED = "index existed"

)
type  ElkEngine struct {
	cli *elastic.Client
}



func (p *ElkEngine)Create(index string,types string,id string,data interface{}) (error)  {
	if nil != p{
		if (reflect.TypeOf(data).Kind() == reflect.String)  || (reflect.TypeOf(data).Kind() == reflect.Struct){
			resp, err := p.cli.Index().
				Index(index).
				BodyJson(data).
				Do(context.Background())
			if err != nil {
				log.Print("create error",err)
				return err
			}
			log.Print(resp)
		}else{
			log.Print(reflect.TypeOf(data).Kind())
			return errors.New(INPUT_TYPE_ERROR)
		}
	}else{
		return errors.New(ERROR_PTR)
	}
	return nil
}

func (p *ElkEngine)Delete(query elastic.Query,index string) error{
	if nil != p{
		_, err := p.cli.DeleteByQuery().Index(index).Query(query).
			Do(context.Background())
		if err != nil {
			log.Print(err)
			return  err
		}

	}else{
		return errors.New(ERROR_PTR)
	}
	return nil
}
/*

*/
func (p *ElkEngine)Query(index string,query elastic.Query,typ reflect.Type,
	limit int,offset int) ([]interface{},[]string,error) {
	rets := []interface{}{}
	if nil != p{
		if(limit == 0){
			res, err := p.cli.Search(index).Query(query).Do(context.Background())
			if err != nil {
				print(err)
				return  nil,nil,err
			}
			
			id := []string{}
			for _,vs := range res.Hits.Hits{
				id = append(id,vs.Id)
			}
			return rets,id,nil
		}else{
			res, err := p.cli.Search(index).Query(query).Size(limit).From(limit*offset).Do(context.Background())
			if err != nil {
				print(err)
				return  nil,nil,err
			}
			id := []string{}
			for _,vs := range res.Hits.Hits{
				id = append(id,vs.Id)
				data,e  := vs.Source.MarshalJSON()
				if nil != e{
					log.Print(e.Error())
				}
				obj := utils.ReflectMakeNew(typ)
				mapobj := map[string]interface{}{}
				e = json.Unmarshal(data,&mapobj)
				if nil != e{
					log.Print(e.Error())
				}
				// for k,_ := range mapobj{
				// 	value := reflect.ValueOf(obj)
				// }
				log.Print(obj)
				rets = append(rets,obj)
				log.Print(string(data))
			}
			return rets,id,nil
		}
	}else{
		return nil,nil,errors.New(ERROR_PTR)
	}
}

func (p *ElkEngine)Update(index string,types string,id string,data map[string]interface{}) error {
	if nil != p {
		_, err := p.cli.Update().
			Index(index).
			Id(id).
			Doc(data).
			Do(context.Background())
		if err != nil {
			println(err.Error())
			return err
		}
	}
	return errors.New(ERROR_PTR)
}
func (p *ElkEngine)CreateIndex(index string,typemaping string)  error{
	if nil != p {
		exists, err := p.cli.IndexExists(index).Do(context.Background())
		if err != nil {
			// Handle error
			log.Print(err)
			return err
		}
		if exists{
			return errors.New(INDEX_EXISTED)
		}
		createIndex, err := p.cli.CreateIndex(index).Body(typemaping).Do(context.Background())
		if err != nil {
			log.Print(err)
			return err
		}
		if !createIndex.Acknowledged {
			return errors.New("create index error")
			// Not acknowledged
		}
		return  nil
	}
	return errors.New(ERROR_PTR)
}

func (p *ElkEngine)IndexExisted(index string)  (bool,error ){
	if nil != p {
		exists, err := p.cli.IndexExists(index).Do(context.Background())
		if exists{
			return true,nil
		}
		if err != nil {
			// Handle error
			log.Print(err)
			return false,err
		}
		return false,nil

	}
	return false,nil
}