OpenSearch:Demo code for implementing scroll queries

Create a header file that contains configurations

The configurations that you specify in this header file are used to push and query documents. The configurations include the AccessKey pair, API endpoint, application name, name of the drop-down suggestion model, and options.

<?php
// Import the header file.
require_once("../OpenSearch/Autoloader/Autoloader.php");
use OpenSearch\Client\OpenSearchClient;

// Specify your AccessKey pair.
// Obtain the AccessKey ID and AccessKey secret from environment variables. 
// You must configure environment variables before you run this code. For more information, see the "Configure environment variables" section of this topic.
// Specify the AccessKey ID.
$accessKeyId = getenv('ALIBABA_CLOUD_ACCESS_KEY_ID');
// Specify the AccessKey secret.
$secret = getenv('ALIBABA_CLOUD_ACCESS_KEY_SECRET');
// Specify the endpoint of the OpenSearch API in your region. You can obtain the endpoint on the details page of the application in the OpenSearch console.
$endPoint = '<region endPoint>';
// Specify the application name.
$appName = '<app name>';
// Specify the name of the drop-down suggestion model.
$suggestName = '<suggest name>';
// Enable the debugging mode.
$options = array('debug' => true);
// Create an OpenSearchClient object.
$client = new OpenSearchClient($accessKeyId, $secret, $endPoint, $options);

The following sample code shows how to implement scroll queries:

<?php
header("Content-Type:text/html;charset=utf-8");
// Import the header file.
require_once("Config.inc.php");
use OpenSearch\Client\SearchClient;
use OpenSearch\Util\SearchParamsBuilder;

$searchClient = new SearchClient($client);
// Create a SearchParamsBuilder object and specify the parameters.
$params = new SearchParamsBuilder();
// Specify the number of documents to be returned for each scroll query. You do not need to specify an offset for returned results.
$params->setHits(1);
// Specify the application name.
$params->setAppName('The application name');
// Specify a search query.
$params->setQuery("name: 'Search'");
// Specify the data format of returned results. Supported formats are JSON and FULLJSON. In this example, the data format is set to FULLJSON.
$params->setFormat("fulljson");

// In OpenSearch SDK for PHP V3, scroll queries support sorting only based on a single field. The field must be of the INT type. We recommend that you configure sorting based on the primary key. This prevents repeated document retrieval that is caused by data updates during queries.
$params->addSort('id', SearchParamsBuilder::SORT_INCREASE);

// Specify a filter condition.
$params->setFilter('id>0');

// Specify the fields to be returned.
$params->setFetchFields(array('id','name','phone','int_arr','literal_arr','float_arr','cate_id'));

// Specify a validity period for the scroll ID to be used by the next scroll query, in minutes. In this example, the value is set to 3m. You do not need to specify a scroll ID for the first scroll query. The first scroll query returns a scroll ID that can be used by the next scroll query.
 $params->setScrollExpire('3m');
// Run the query and return the results.
$ret = $searchClient->execute($params->build())->result;

for($i=0;$i<json_decode($ret)->result->viewtotal;$i++){
    // Use the scroll ID of the first scroll query as a query parameter.
    $params->setScrollId(json_decode($ret)->result->scroll_id);
    // Run the query again and return the results.
    $ret = $searchClient->execute($params->build())->result;
    // Display the returned results.
    print_r($ret.'<br/><br/>');
}