func ExampleSearchService() {
// Get a client to the local Elasticsearch instance.
client, err := elastic.NewClient()
if err != nil {
// Handle error
panic(err)
}
// Search with a term query
termQuery := elastic.NewTermQuery("user", "olivere")
searchResult, err := client.Search().
Index("twitter"). // search in index "twitter"
Query(&termQuery). // specify the query
Sort("user", true). // sort by "user" field, ascending
From(0).Size(10). // take documents 0-9
Pretty(true). // pretty print request and response JSON
Do() // execute
if err != nil {
// Handle error
panic(err)
}
// searchResult is of type SearchResult and returns hits, suggestions,
// and all kinds of other information from Elasticsearch.
fmt.Printf("Query took %d milliseconds\n", searchResult.TookInMillis)
// Number of hits
if searchResult.Hits != nil {
fmt.Printf("Found a total of %d tweets\n", searchResult.Hits.TotalHits)
// Iterate through results
for _, hit := range searchResult.Hits.Hits {
// hit.Index contains the name of the index
// Deserialize hit.Source into a Tweet (could also be just a map[string]interface{}).
var t Tweet
err := json.Unmarshal(*hit.Source, &t)
if err != nil {
// Deserialization failed
}
// Work with tweet
fmt.Printf("Tweet by %s: %s\n", t.User, t.Message)
}
} else {
// No hits
fmt.Print("Found no tweets\n")
}
}
func Example() {
errorlog := log.New(os.Stdout, "APP ", log.LstdFlags)
// Obtain a client. You can provide your own HTTP client here.
client, err := elastic.NewClient(elastic.SetErrorLog(errorlog))
if err != nil {
// Handle error
panic(err)
}
// Trace request and response details like this
//client.SetTracer(log.New(os.Stdout, "", 0))
// Ping the Elasticsearch server to get e.g. the version number
info, code, err := client.Ping().Do()
if err != nil {
// Handle error
panic(err)
}
fmt.Printf("Elasticsearch returned with code %d and version %s", code, info.Version.Number)
// Getting the ES version number is quite common, so there's a shortcut
esversion, err := client.ElasticsearchVersion("http://127.0.0.1:9200")
if err != nil {
// Handle error
panic(err)
}
fmt.Printf("Elasticsearch version %s", esversion)
// Use the IndexExists service to check if a specified index exists.
exists, err := client.IndexExists("twitter").Do()
if err != nil {
// Handle error
panic(err)
}
if !exists {
// Create a new index.
createIndex, err := client.CreateIndex("twitter").Do()
if err != nil {
// Handle error
panic(err)
}
if !createIndex.Acknowledged {
// Not acknowledged
}
}
// Index a tweet (using JSON serialization)
tweet1 := Tweet{User: "******", Message: "Take Five", Retweets: 0}
put1, err := client.Index().
Index("twitter").
Type("tweet").
Id("1").
BodyJson(tweet1).
Do()
if err != nil {
// Handle error
panic(err)
}
fmt.Printf("Indexed tweet %s to index %s, type %s\n", put1.Id, put1.Index, put1.Type)
// Index a second tweet (by string)
tweet2 := `{"user" : "olivere", "message" : "It's a Raggy Waltz"}`
put2, err := client.Index().
Index("twitter").
Type("tweet").
Id("2").
BodyString(tweet2).
Do()
if err != nil {
// Handle error
panic(err)
}
fmt.Printf("Indexed tweet %s to index %s, type %s\n", put2.Id, put2.Index, put2.Type)
// Get tweet with specified ID
get1, err := client.Get().
Index("twitter").
Type("tweet").
Id("1").
Do()
if err != nil {
// Handle error
panic(err)
}
if get1.Found {
fmt.Printf("Got document %s in version %d from index %s, type %s\n", get1.Id, get1.Version, get1.Index, get1.Type)
}
// Flush to make sure the documents got written.
_, err = client.Flush().Index("twitter").Do()
if err != nil {
panic(err)
}
// Search with a term query
termQuery := elastic.NewTermQuery("user", "olivere")
searchResult, err := client.Search().
Index("twitter"). // search in index "twitter"
Query(&termQuery). // specify the query
Sort("user", true). // sort by "user" field, ascending
From(0).Size(10). // take documents 0-9
Pretty(true). // pretty print request and response JSON
Do() // execute
if err != nil {
// Handle error
panic(err)
}
// searchResult is of type SearchResult and returns hits, suggestions,
// and all kinds of other information from Elasticsearch.
fmt.Printf("Query took %d milliseconds\n", searchResult.TookInMillis)
// Number of hits
if searchResult.Hits != nil {
fmt.Printf("Found a total of %d tweets\n", searchResult.Hits.TotalHits)
// Iterate through results
for _, hit := range searchResult.Hits.Hits {
// hit.Index contains the name of the index
// Deserialize hit.Source into a Tweet (could also be just a map[string]interface{}).
var t Tweet
err := json.Unmarshal(*hit.Source, &t)
if err != nil {
// Deserialization failed
}
// Work with tweet
fmt.Printf("Tweet by %s: %s\n", t.User, t.Message)
}
} else {
// No hits
fmt.Print("Found no tweets\n")
}
// Update a tweet by the update API of Elasticsearch.
// We just increment the number of retweets.
update, err := client.Update().Index("twitter").Type("tweet").Id("1").
Script("ctx._source.retweets += num").
ScriptParams(map[string]interface{}{"num": 1}).
Upsert(map[string]interface{}{"retweets": 0}).
Do()
if err != nil {
// Handle error
panic(err)
}
fmt.Printf("New version of tweet %q is now %d", update.Id, update.Version)
// ...
// Delete an index.
deleteIndex, err := client.DeleteIndex("twitter").Do()
if err != nil {
// Handle error
panic(err)
}
if !deleteIndex.Acknowledged {
// Not acknowledged
}
}