Add Autocomplete to Your Application

how-to

March 23, 2025

+ 12

Use autocomplete to add suggestions for a user’s Search query as they type in your application.

After you create and configure a Search index that supports autocomplete, configure your application to return results from the Search Service.

Prerequisites

You have the Search Service enabled on a node in your database. For more information about how to deploy a new node and Services on your database, see Manage Nodes and Clusters.
You have a bucket with scopes and collections in your database. For more information about how to create a bucket, see Create a Bucket.
You have created a compatible Search index. For more information, see Configure an Autocomplete Search Index.
Your user account has the Search Admin role for the bucket where you created the Search index.
You have the hostname or IP address for the node in your database where you’re running the Search Service. For more information about where to find the IP address for your node, see List Cluster Nodes.

Procedure

To add autocomplete with the Search Service to your application:

To test that your Search index was configured correctly, do one of the following:
1. Run a Search query from the REST API with 2-8 characters in the query property.
2. Run a Search query from the Web Console with 2-8 characters in the Search field.
For example, with the travel-sample bucket, you could enter the strings Be, Bea, Beau, and Beauf to find a document with the text Beaufort Hotel.

Configure your application to return results from the Search Service.

The following examples simulate a user typing an input string and return search results for each partial string:

C#
Go
Java
JavaScript
Python

csharp
ViewCopy
using Couchbase;
using Couchbase.Search.Queries.Simple;

await using var cluster = await Cluster.ConnectAsync(new ClusterOptions
{
    ConnectionString = "CB_HOSTNAME",
    UserName = "CB_USERNAME",
    Password = "CB_PASSWORD",
    Buckets = new List<string>{"travel-sample"}
}.ApplyProfile("wan-development"));

var searchString = "Beaufort Hotel";
for (var i = 2; i <= 8; i++)
{
    var lettersEntered = searchString.Substring(0, i);
    Console.WriteLine($"Input <{lettersEntered}>, len: {lettersEntered.Length}");
    await FtsMatchPrefix(lettersEntered);
}

async Task FtsMatchPrefix(string letters)
{
    try
    {
        var results = await cluster.SearchQueryAsync("e-ngram-2-8",
            new QueryStringQuery(letters),
            options =>
            {
                options.Limit(8);
                options.Fields("name");
            });
        results.Hits.ToList().ForEach(row => { Console.WriteLine($"{row.Id}, {row.Fields}"); });
        Console.WriteLine(results);
    }
    catch (Exception e)
    {
        Console.WriteLine(e);
    }
}

go
ViewCopy
package main

import (
    "os"
    "fmt"
    "math"
    "log"
    "github.com/couchbase/gocb/v2"
    "github.com/couchbase/gocb/v2/search"
)

func main() {
    cluster, err := gocb.Connect(
	os.Getenv("CB_HOSTNAME"),                    
	gocb.ClusterOptions{
        Authenticator: gocb.PasswordAuthenticator{
            Username: os.Getenv("CB_USERNAME"),      
            Password: os.Getenv("CB_PASSWORD"),      
        },
    })
    if err != nil {
        log.Fatal(err)
    }

    iterStr := "Beaufort Hotel"
    maxsz := int(math.Min(float64(len(iterStr)), float64(8)))
    for i := 2;  i <= maxsz; i++ {
        testStr := iterStr[0:i]
	fmt.Printf("Input <%s>, len: %d\n", testStr, len(testStr));
	results, err := cluster.SearchQuery(
	    "e-ngram-2-8",
	    search.NewQueryStringQuery(testStr), 
	    &gocb.SearchOptions { Fields: []string{"name"}, Limit: 8, },
	)
	if err != nil {
	    log.Fatal(err)
	}

	for results.Next() {
	    row := results.Row()
	    docID := row.ID
	    var fields interface {}
	    err := row.Fields( & fields)
	    if err != nil {
		panic(err)
	    }
	    fmt.Printf("Document ID: %s, fields: %v\n", docID, fields)
	}

	err = results.Err()
	if err != nil {
	    log.Fatal(err)
	}
    }
}

java
ViewCopy
import com.couchbase.client.java.Cluster;
import com.couchbase.client.java.json.JsonObject;
import com.couchbase.client.java.search.SearchOptions;
import com.couchbase.client.java.search.SearchQuery;
import com.couchbase.client.java.search.result.SearchResult;
import com.couchbase.client.java.search.result.SearchRow;

public class MockTypeAheadEnGram {
  static String connstrn = System.getenv("CB_HOSTNAME"); 
  static String username = System.getenv("CB_USERNAME"); 
  static String password = System.getenv("CB_PASSWORD"); 
  
  public static void main(String... args) {
    Cluster cluster = Cluster.connect(connstrn, username, password);
    
    String iterStr = "Beaufort Hotel";
    for (int i=2; i<=Math.min(8, iterStr.length());i++) {
    	String testStr = iterStr.substring(0, i);
    	System.out.println("Input <" + testStr + ">, len: " + testStr.length());
    
    	SearchQuery query = SearchQuery.queryString(testStr);
    	SearchOptions options = SearchOptions.searchOptions().limit(8).skip(0).explain(false).fields("name");
    	SearchResult result = cluster.searchQuery("e-ngram-2-8" , query, options);
    	for (SearchRow row : result.rows()) {
    		System.out.println(row.id() + "," + row.fieldsAs(JsonObject.class) );
    	}
    }
  }
}

javascript
ViewCopy
const couchbase = require('couchbase')

const main = async () => {
  const hostname = process.env.CB_HOSTNAME
  const username = process.env.CB_USERNAME
  const password = process.env.CB_PASSWORD
  const bucketName = 'travel-sample'

  const cluster = await couchbase.connect(hostname, {username: username, password: password })

  const ftsMatchPrefix = async (term) => {
    try {
      const result =  await cluster.searchQuery(
        "e-ngram-2-8",
        couchbase.SearchQuery.queryString(term), { limit: 8, fields: ["name"] }
      )
      result.rows.forEach((row) => { console.log(row.id,row.fields)})
    } catch (error) {
      console.error(error)
    }
  }

  const inputStr = "Beaufort Hotel"
  for (let i = 2; i <= 8; i++) {
    var testStr = inputStr.substring(0, i);
    console.log("Input <" + testStr + ">, len: " + testStr.length)
    const res = await ftsMatchPrefix(testStr)
  }
}

main()

python
ViewCopy
from couchbase.cluster import Cluster, ClusterOptions
from couchbase.auth import PasswordAuthenticator
from couchbase.exceptions import CouchbaseException
import couchbase.search as search
import os

username = os.getenv("CB_USERNAME", default=None)
password = os.getenv("CB_PASSWORD", default=None)
hostname = os.getenv("CB_HOSTNAME", default=None)

cluster = Cluster.connect(
    "couchbase://" + hostname,
    ClusterOptions(PasswordAuthenticator(username,password)))

try:
    inputStr = "Beaufort Hotel"
    for i in range(2, min(8,len(inputStr))):
        testStr = inputStr[0:i]
        print("Input <" + testStr + ">, len: " + str(len(testStr)));

        result = cluster.search_query(
            "e-ngram-2-8", 
            search.QueryStringQuery(testStr),
            search.SearchOptions(limit=8, fields=["name"]))

        for row in result.rows():
            print(row.id,row.fields)

except CouchbaseException as ex:
    import traceback
    traceback.print_exc()

Next Steps

After you add autocomplete to your application, to improve your search results, you can:

Customize your Search index with the Web Console.
Change the JSON payload for your Search index.