Scrollingedit

The Scrolling functionality of Elasticsearch is used to paginate over many documents in a bulk manner, such as exporting all the documents belonging to a single user. It is more efficient than regular search because it doesn’t need to maintain an expensive priority queue ordering the documents.

Scrolling works by maintaining a "point in time" snapshot of the index which is then used to page over. This window allows consistent paging even if there is background indexing/updating/deleting. First, you execute a search request with scroll enabled. This returns a "page" of documents, and a scroll_id which is used to continue paginating through the hits.

More details about scrolling can be found in the Link: reference documentation.

This is an example which can be used as a template for more advanced operations:

$client = ClientBuilder::create()->build();
$params = [
    "scroll" => "30s",          // how long between scroll requests. should be small!
    "size" => 50,               // how many results *per shard* you want back
    "index" => "my_index",
    "body" => [
        "query" => [
            "match_all" => new \stdClass()
        ]
    ]
];

// Execute the search
// The response will contain the first batch of documents
// and a scroll_id
$response = $client->search($params);

// Now we loop until the scroll "cursors" are exhausted
while (isset($response['hits']['hits']) && count($response['hits']['hits']) > 0) {

    // **
    // Do your work here, on the $response['hits']['hits'] array
    // **

    // When done, get the new scroll_id
    // You must always refresh your _scroll_id!  It can change sometimes
    $scroll_id = $response['_scroll_id'];

    // Execute a Scroll request and repeat
    $response = $client->scroll([
            "scroll_id" => $scroll_id,  //...using our previously obtained _scroll_id
            "scroll" => "30s"           // and the same timeout window
        ]
    );
}