Issue #774: Create and delete index

main.go

package main

import (
	"context"
	"log"

	"github.com/olivere/elastic"
)

const (
	indexName = "films"
	mapping   = `
	{
		"settings":{
			"number_of_shards":1,
			"number_of_replicas":0
		},
		"mappings":{
			"_doc":{
				"properties":{
					"title":{
						"type":"keyword"
					},
					"genre":{
						"type":"keyword"
					},
					"year":{
						"type":"long"
					},
					"director":{
						"type":"keyword"
					}
				}
			}
		}
	}
	`
)

func main() {
	log.Print("Connecting...")
	opts := []elastic.ClientOptionFunc{
		// Uncomment next line to show response from Elasticsearch
		//elastic.SetTraceLog(log.New(os.Stdout, "", 0)),
	}
	client, err := elastic.NewClient(opts...)
	if err != nil {
		log.Printf("unable to connect: %v", err)
	}

	// Check if index exists
	log.Print("Check if index exists...")
	ctx := context.Background()
	exists, err := client.IndexExists(indexName).Do(ctx)
	if err != nil {
		log.Fatalf("unable to check if index exists: %v", err)
	}
	if exists {
		log.Print("Removing existing index...")
		_, err = client.DeleteIndex(indexName).Do(ctx)
		if err != nil {
			log.Fatalf("unable to delete index: %v", err)
		}
	}
	// Create index with mapping
	log.Print("Create index with mapping...")
	_, err = client.CreateIndex(indexName).Body(mapping).Do(ctx)
	if err != nil {
		log.Fatalf("unable to create index: %v", err)
	}
}