Elasticsearch Scan/Scroll

elasticsearch-scan-scroll-sample.php

// https://www.elastic.co/guide/en/elasticsearch/client/php-api/5.0/_search_operations.html#_scan_scroll

$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()
        ]
    ]
];

$docs = $client->search($params);   // Execute the search
$scroll_id = $docs['_scroll_id'];   // The response will contain no results, just a _scroll_id

// Now we loop until the scroll "cursors" are exhausted
while (\true) {

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

    // Check to see if we got any search hits from the scroll
    if (count($response['hits']['hits']) > 0) {
        // If yes, Do Work Here

        // Get new scroll_id
        // Must always refresh your _scroll_id!  It can change sometimes
        $scroll_id = $response['_scroll_id'];
    } else {
        // No results, scroll cursor is empty.  You've exported all the data
        break;
    }
}