Elasticsearch PHP client

This is the official PHP client for Elasticsearch.

Contents

• Getting started
• Configuration
  • Use Elastic Cloud
• Usage
  • Index a document
  • Search a document
  • Delete a document
• Versioning
• Backward Incompatible Changes
• Mock the Elasticsearch client
• FAQ
• Contribute
• License

---

Getting started 🐣

Using this client assumes that you have an Elasticsearch server installed and running.

You can install the client in your PHP project using composer:

composer require elasticsearch/elasticsearch

After the installation you can connect to Elasticsearch using the ClientBuilder class. For instance, if your Elasticsearch is running on localhost:9200 you can use the following code:

use Elastic\Elasticsearch\ClientBuilder;

$client = ClientBuilder::create()
    ->setHosts(['localhost:9200'])
    ->build();

// Info API
$response = $client->info();

echo $response['version']['number']; // 8.0.0

The $response is an object of Elastic\Elasticsearch\Response\Elasticsearch class that implements ElasticsearchInterface, PSR-7 ResponseInterface and ArrayAccess.

This means the $response is a PSR-7 object:

echo $response->getStatusCode(); // 200
echo (string) $response->getBody(); // Response body in JSON

and also an "array", meaning you can access the response body as an associative array, as follows:

echo $response['version']['number']; // 8.0.0

var_dump($response->asArray());  // response body content as array

Moreover, you can access the response body as object, string or bool:

echo $response->version->number; // 8.0.0

var_dump($response->asObject()); // response body content as object
var_dump($response->asString()); // response body as string (JSON)
var_dump($response->asBool());   // true if HTTP response code between 200 and 300

Configuration

Elasticsearch 8.0 offers security by default, that means it uses TLS for protect the communication between client and server.

In order to configure elasticsearch-php for connecting to Elasticsearch 8.0 we need to have the certificate authority file (CA).

You can install Elasticsearch in different ways, for instance using Docker you need to execute the followind command:

docker pull docker.elastic.co/elasticsearch/elasticsearch:8.0.1

Once you have the docker image installed, you can execute Elasticsearch, for instance using a single-node cluster configuration, as follows:

docker network create elastic
docker run --name es01 --net elastic -p 9200:9200 -p 9300:9300 -it docker.elastic.co/elasticsearch/elasticsearch:8.0.1

This command creates an elastic Docker network and start Elasticsearch using the port 9200 (default).

When you run the docker image a password is generated for the elastic user and it's printed to the terminal (you might need to scroll back a bit in the terminal to view it). You have to copy it since we will need to connect to Elasticsearch.

Now that Elasticsearch is running we can get the http_ca.crt file certificate. We need to copy it from the docker instance, using the following command:

docker cp es01:/usr/share/elasticsearch/config/certs/http_ca.crt .

Once we have the http_ca.crt certificate and the password, copied during the start of Elasticsearch, we can use it to connect with elasticsearch-php as follows:

$client = ClientBuilder::create()
    ->setHosts(['https://localhost:9200'])
    ->setBasicAuthentication('elastic', 'password copied during Elasticsearch start')
    ->setCABundle('path/to/http_ca.crt')
    ->build();

For more information about the Docker configuration of Elasticsearch you can read the official documentation here.

Use Elastic Cloud

You can use Elastic Cloud as server with elasticsearch-php. Elastic Cloud is the PaaS solution offered by Elastic.

For connecting to Elastic Cloud you just need the Cloud ID and the API key.

You can get the Cloud ID from the My deployment page of your dashboard (see the red rectangle reported in the screenshot).

You can generate an API key in the Management page under the section Security.

When you click on Create API key button you can choose a name and set the other options (for example, restrict privileges, expire after time, and so on).

After this step you will get the API keyin the API keys page.

IMPORTANT: you need to copy and store the API keyin a secure place, since you will not be able to view it again in Elastic Cloud.

Once you have collected the Cloud ID and the API key, you can use elasticsearch-php to connect to your Elastic Cloud instance, as follows:

$client = ClientBuilder::create()
    ->setElasticCloudId('insert here the Cloud ID')
    ->setApiKey('insert here the API key')
    ->build();

Usage

The elasticsearch-php client offers 400+ endpoints for interacting with Elasticsearch. A list of all these endpoints is available in the official documentation of Elasticsearch APIs.

Here we reported the basic operation that you can perform with the client: index, search and delete.

Index a document

You can store (index) a JSON document in Elasticsearch using the following code:

use Elastic\Elasticsearch\Exception\ClientResponseException;
use Elastic\Elasticsearch\Exception\ServerResponseException;

$params = [
    'index' => 'my_index',
    'body'  => [ 'testField' => 'abc']
];

try {
  $response = $client->index($params);
} catch (ClientResponseException $e) {
  // manage the 4xx error
} catch (ServerResponseException $e) {
  // manage the 5xx error
} catch (Exception $e) {
  // eg. network error like NoNodeAvailableException
}

print_r($response->asArray());  // response body content as array

Elasticsearch stores the {"testField":"abc"} JSON document in the my_index index. The ID of the document is created automatically by Elasticsearch and stored in $response['_id'] field value. If you want to specify an ID for the document you need to store it in $params['id'].

You can manage errors using ClientResponseException and ServerResponseException. The PSR-7 response is available using $e->getResponse() and the HTTP status code is available using $e->getCode().

Search a document

Elasticsearch provides many different way to search documents. The simplest search that you can perform is a match query, as follows:

$params = [
    'index' => 'my_index',
    'body'  => [
        'query' => [
            'match' => [
                'testField' => 'abc'
            ]
        ]
    ]
];
$response = $client->search($params);

printf("Total docs: %d\n", $response['hits']['total']['value']);
printf("Max score : %.4f\n", $response['hits']['max_score']);
printf("Took      : %d ms\n", $response['took']);

print_r($response['hits']['hits']); // documents

Using Elasticsearch you can perform different query search, for more information we suggest toread the official documention reported here.

Delete a document

You can delete a document specifing the index name and the ID of the document, as follows:

use Elastic\Elasticsearch\Exception\ClientResponseException;

try {
    $response = $client->delete([
        'index' => 'my_index',
        'id' => 'my_id'
    ]);
} catch (ClientResponseException $e) {
    if ($e->getCode() === 404) {
        // the document does not exist
    }
}
if ($response['acknowledge'] === 1) {
    // the document has been delete
}

For more information about the Elasticsearch REST API you can read the official documentation here.

Versioning

This client is versioned and released alongside Elasticsearch server.

To guarantee compatibility, use the most recent version of this library within the major version of the corresponding Enterprise Search implementation.

For example, for Elasticsearch 7.16, use 7.16 of this library or above, but not 8.0.

Backward Incompatible Changes 💥

The 8.0.0 version of elasticsearch-php contains a new implementation compared with 7.x. It supports PSR-7 for HTTP messages and PSR-18 for HTTP client communications.

We tried to reduce the BC breaks as much as possible with 7.x but there are some (big) differences:

• we changed the namespace, now everything is under Elastic\Elasticsearch
• we used the elastic-transport-php library for HTTP communications;
• we changed the Exception model, using the namespace Elastic\Elasticsearch\Exception. All the exceptions extends the ElasticsearchException interface, as in 7.x
• we changed the response type of each endpoints using an Elasticsearch response class. This class wraps a a PSR-7 response allowing the access of the body response as array or object. This means you can access the API response as in 7.x, no BC break here! 👼
• we changed the ConnectionPool in NodePool. The connection naming was ambigous since the objects are nodes (hosts)

You can have a look at the BREAKING_CHANGES file for more information.

Mock the Elasticsearch client

If you need to mock the Elasticsearch client you just need to mock a PSR-18 HTTP Client.

For instance, you can use the php-http/mock-client as follows:

use Elastic\Elasticsearch\ClientBuilder;
use Elastic\Elasticsearch\Response\Elasticsearch;
use Http\Mock\Client;
use Nyholm\Psr7\Response;

$mock = new Client(); // This is the mock client

$client = ClientBuilder::create()
    ->setHttpClient($mock)
    ->build();

// This is a PSR-7 response
$response = new Response(
    200, 
    [Elasticsearch::HEADER_CHECK => Elasticsearch::PRODUCT_NAME],
    'This is the body!'
);
$mock->addResponse($response);

$result = $client->info(); // Just calling an Elasticsearch endpoint

echo $result->asString(); // This is the body!

We are using the ClientBuilder::setHttpClient() to set the mock client. You can specify the response that you want to have using the addResponse($response) function. As you can see the $response is a PSR-7 response object. In this example we used the Nyholm\Psr7\Response object from the nyholm/psr7 project. If you are using PHPUnit you can even mock the ResponseInterface as follows:

$response = $this->createMock('Psr\Http\Message\ResponseInterface');

Notice: we added a special header in the HTTP response. This is the product check header, and it is required for guarantee that elasticsearch-php is communicating with an Elasticsearch server 8.0+.

For more information you can read the Mock client section of PHP-HTTP documentation.

FAQ 🔮

Where do I report issues with the client?

If something is not working as expected, please open an issue.

Where else can I go to get help?

You can checkout the Elastic community discuss forums.

Contribute 🚀

We welcome contributors to the project. Before you begin, some useful info...

• If you want to contribute to this project you need to subscribe to a Contributor Agreement.
• Before opening a pull request, please create an issue to discuss the scope of your proposal.
• If you want to send a PR for version 8.0 please use the 8.0 branch, for 8.1 use the 8.1 branch and so on.
• Never send PR to master unless you want to contribute to the development version of the client (master represents the next major version).
• Each PR should include a unit test using PHPUnit. If you are not familiar with PHPUnit you can have a look at the reference.

Thanks in advance for your contribution! ❤️

License 📗

MIT © Elastic