gaoyixia/vendor/elasticsearch/elasticsearch/docs/endpoint-closure.asciidoc

[[endpoint-closure]]
=== Set the Endpoint closure

The client uses an Endpoint closure to dispatch API requests to the correct 
Endpoint object. A namespace object will construct a new Endpoint via this 
closure, which means this is a handy location if you wish to extend the 
available set of API endpoints available.

For example, we could add a new endpoint like so:

[source,php]
----

$transport = $this->transport;
$serializer = $this->serializer;

$newEndpoint = function ($class) use ($transport, $serializer) {
    if ($class == 'SuperSearch') {
        return new MyProject\SuperSearch($transport);
    } else {
        // Default handler
        $fullPath = '\\Elasticsearch\\Endpoints\\' . $class;
        if ($class === 'Bulk' || $class === 'Msearch' || $class === 'MPercolate') {
            return new $fullPath($transport, $serializer);
        } else {
            return new $fullPath($transport);
        }
    }
};

$client = ClientBuilder::create()
            ->setEndpoint($newEndpoint)
            ->build();
----

Obviously, by doing this you take responsibility that all existing endpoints 
still function correctly. And you also assume the responsibility of correctly 
wiring the Transport and Serializer into each endpoint.