Get started with the serverless Go client
editGet started with the serverless Go client
editThis client is for use with Elasticsearch Serverless only. See also the Elasticsearch clients.
This page guides you through the installation process of the Go client for Elasticsearch Serverless, shows you how to initialize the client, and how to perform basic Elasticsearch operations with it.
Requirements
edit- Go 1.20 or higher installed on your system.
Installation
editUsing the command line
editYou can install the Go client with the following commands:
go get -u github.com/elastic/elasticsearch-serverless-go@latest
Imports
editThe following snippets use these imports:
import ( "context" "encoding/json" "fmt" "log" "strconv" "github.com/elastic/elasticsearch-serverless-go" "github.com/elastic/elasticsearch-serverless-go/typedapi/types" "github.com/elastic/elasticsearch-serverless-go/typedapi/types/enums/result" )
Initialize the client
editInitialize the client using your API key and Elasticsearch endpoint:
client, err := elasticsearch.NewClient(elasticsearch.Config{ APIKey: "you_api_key", Address: "https://my-project-url", }) if err != nil { log.Fatal(err) }
To get API keys for the Elasticsearch endpoint for a project, see Get started.
Using the API
editAfter you’ve initialized the client, you can start ingesting documents. You can
use the bulk
API for this. This API enables you to index, update, and delete
several documents in one request.
Creating an index and ingesting documents
editYou can call the bulk
API with a body parameter, an array of hashes that
define the action, and a document.
The following is an example of indexing some classic books into the books
index:
type Book struct { Name string `json:"name"` Author string `json:"author"` ReleaseDate string `json:"release_date"` PageCount int `json:"page_count"` } books := []Book{ {Name: "Snow Crash", Author: "Neal Stephenson", ReleaseDate: "1992-06-01", PageCount: 470}, {Name: "Revelation Space", Author: "Alastair Reynolds", ReleaseDate: "2000-03-15", PageCount: 585}, {Name: "1984", Author: "George Orwell", ReleaseDate: "1949-06-08", PageCount: 328}, {Name: "Fahrenheit 451", Author: "Ray Bradbury", ReleaseDate: "1953-10-15", PageCount: 227}, {Name: "Brave New World", Author: "Aldous Huxley", ReleaseDate: "1932-06-01", PageCount: 268}, {Name: "The Handmaid's Tale", Author: "Margaret Atwood", ReleaseDate: "1985-06-01", PageCount: 311}, } indexName := "books" bulk := client.Bulk() for i, book := range books { id := strconv.Itoa(i) err := bulk.CreateOp(types.CreateOperation{Index_: &indexName, Id_: &id}, book) if err != nil { log.Fatal(err) } } bulkRes, err := bulk.Do(context.TODO()) if err != nil { log.Fatal(err) } fmt.Printf("Bulk: %#v\n", bulkRes.Items)
When you use the client to make a request to Elasticsearch Serverless, it returns an API
response object. You can access the body values directly as seen on
the previous example with bulkRes
.
Getting documents
editYou can get documents by using the following code:
getRes, err := client.Get(indexName, "5").Do(context.TODO()) if err != nil { log.Fatal(err) } book := Book{} if err := json.Unmarshal(getRes.Source_, &book); err != nil { log.Fatal(err) } fmt.Printf("Get book: %#v\n", book)
Searching
editNow that some data is available, you can search your documents using the
search
API:
searchRes, err := client.Search(). Index("books"). Q("snow"). Do(context.TODO()) if err != nil { log.Fatal(err) } bookSearch := []Book{} for _, hit := range searchRes.Hits.Hits { book := Book{} if err := json.Unmarshal(hit.Source_, &book); err != nil { log.Fatal(err) } bookSearch = append(bookSearch, book) } fmt.Printf("Search books: %#v\n", bookSearch)
Updating a document
editYou can call the Update
API to update a document, in this example updating the
page_count
for "The Handmaid’s Tale" with id "5":
updateRes, err := client.Update("books", "5"). Doc( struct { PageCount int `json:"page_count"` }{PageCount: 312}, ). Do(context.TODO()) if err != nil { log.Fatal(err) } if updateRes.Result == result.Updated { fmt.Printf("Update book: %#v\n", updateRes) }
Deleting a document
editYou can call the Delete
API to delete a document:
deleteRes, err := client.Delete("books", "5").Do(context.TODO()) if err != nil { log.Fatal(err) } if deleteRes.Result == result.Deleted { fmt.Printf("Delete book: %#v\n", deleteRes) }
Deleting an index
editindexDeleteRes, err := client.Indices.Delete("books").Do(context.TODO()) if err != nil { log.Fatal(err) } if indexDeleteRes.Acknowledged { fmt.Printf("Delete index: %#v\n", indexDeleteRes) }