<?php
/*
 * Copyright 2013 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
include_once "templates/base.php";
echo pageHeader("Batching Queries");

/************************************************
  We're going to use the simple access to the
  books API again as an example, but this time we
  will batch up two queries into a single call.
 ************************************************/
set_include_path("../src/" . PATH_SEPARATOR . get_include_path());
require_once 'Google/Client.php';
require_once 'Google/Service/Books.php';
require_once 'Google/Http/Batch.php';

/************************************************
  We create the client and set the simple API
  access key. If you comment out the call to
  setDeveloperKey, the request may still succeed
  using the anonymous quota.
 ************************************************/
$client = new Google_Client();
$client->setApplicationName("Client_Library_Examples");
$apiKey = "<YOUR_API_KEY>"; // Change to your API key. 
// Warn if the API key isn't changed!
if ($apiKey == '<YOUR_API_KEY>') {
  echo missingApiKeyWarning();
} else {
  $client->setDeveloperKey($apiKey);

  $service = new Google_Service_Books($client);

  /************************************************
    To actually make the batch call we need to 
    enable batching on the client - this will apply 
    globally until we set it to false. This causes
    call to the service methods to return the query
    rather than immediately executing.
   ************************************************/
  $client->setUseBatch(true);

  /************************************************
   We then create a batch, and add each query we 
   want to execute with keys of our choice - these
   keys will be reflected in the returned array.
  ************************************************/
  $batch = new Google_Http_Batch($client);
  $optParams = array('filter' => 'free-ebooks');
  $req1 = $service->volumes->listVolumes('Henry David Thoreau', $optParams);
  $batch->add($req1, "thoreau");
  $req2 = $service->volumes->listVolumes('George Bernard Shaw', $optParams);
  $batch->add($req2, "shaw");

  /************************************************
    Executing the batch will send all requests off
    at once.
   ************************************************/
  $results = $batch->execute();

  echo "<h3>Results Of Call 1:</h3>";
  foreach ($results['response-thoreau'] as $item) {
    echo $item['volumeInfo']['title'], "<br /> \n";
  }
  echo "<h3>Results Of Call 2:</h3>";
  foreach ($results['response-shaw'] as $item) {
    echo $item['volumeInfo']['title'], "<br /> \n";
  }
}

echo pageFooter(__FILE__);
