Elasticsearch PHP client overview

The Elasticsearch PHP client is designed to be a low-level client. All methods closely match the REST API and the method structure of other language clients. This makes it easier to get started with a client and switch from one language to another.

It provides a response-handling layer that makes it easier to access HTTP responses in different formats. The PSR-18 HTTP response can be accessed as a PHP array, object, or a raw string. For more details, refer to blog post for Elasticsearch PHP client. Additionally, the client provides helpers to map an ES|QL result directly to a PHP object. For more information, refer to map php result to an object.

The client allows you to make API calls and read the response in multiple formats: associative array, object, raw string, or PSR-7 response.

For a step-by-step quickstart with the client, refer to the Getting started guide .

The Elasticsearch PHP client uses the PSR 7 standard. This standard is a community effort that contains a set of interfaces defined by the PHP Framework Interop Group. For more information, refer to the PSR 7 standard documentation.

The Elasticsearch PHP client is compatible with PHP versions that are currently maintained and supported.

Elasticsearch language clients are forward compatible. This ensures that the client remains compatible with Elasticsearch instances running the same or newer minor versions, preventing any breaking changes. However, for all new features in the newer Elasticsearch versions, the client will support them only after a new client version is released. For example, the 8.12 Elasticsearch PHP client does not support new features in Elasticsearch 8.13. You must upgrade to the 8.13 version of the Elasticsearch PHP client to use them.

Elasticsearch language clients are backward-compatible only with default distributions and there are no guarantees for customized or modified versions. The following table provides the compatibility information between Elasticsearch and Elasticsearch PHP client:

The elasticsearch-php client version 9.x follows the same architecture as 8.x. It continues to support PSR-7 for HTTP messages and PSR-18 for HTTP client communications.

Although we've worked to keep 9.x backward compatible, the following important changes may impact your setup:

• Compatibility with Elasticsearch 9.x: All changes and additions to Elasticsearch APIs 9.x release are reflected in the elasticsearch-php client release. You must use elasticsearch-php client version 9.x to access all new endpoints in Elasticsearch 9.x. Using an older client version will break your code.
• Compatibility with Elasticsearch Serverless:
  • The elastic/elasticsearch-serverless is deprecated, and all its functionality has been merged into the elasticsearch-php client. This doesn't have any impact on the default working of the client.
  • If you use any endpoint available in Serverless, you'll see that the corresponding PHP function contains a @group serverless phpdoc attribute.
  • If you use any endpoint that is not available in Serverless, you'll get a 410 HTTP error with the message: This endpoint exists but is not available when running in serverless mode.
  • If you use a URL managed by Elastic, for example *.elastic.cloud, the 9.x client will recognize that it is communicating with a serverless instance.
  • If you are using a proxy, the 9.x client will recognize that the host is serverless from the first response. Alternatively, you can explicitly specify that the host is serverless using the Client::setServerless(true) function. The argument to this function is set to false by default.
• New transport library with PSR-18 cURL client as default: We've removed the Guzzle dependency from the client. The built-in cURL-based HTTP client will be used by default if no other PSR-18 compatible clients are detected. See release 9.0.0 of elastic-transport-php.

For detailed information on all the breaking changes, refer to breaking changes.