ようやくできた！feedlyの購読者数をJavaScriptのAjaxオンリーで取得する方法

http://cloud.feedly.com/v3/feeds/feed%2F[URLエンコードしたフィードのURL]

{"id":"feed/https://nelog.jp/feed","feedId":"feed/https://nelog.jp/feed","language":"ja","subscribers":204,"title":"寝ログ","velocity":9.3,"topics":["ブログ","【wordpress】","it"],"website":"https://nelog.jp","contentType":"article","description":"寝ながら出来るコトや使えるモノを紹介","twitterScreenName":"MrYhira","twitterFollowers":330,"facebookUsername":"nelog.jp","facebookLikes":71,"partial":true,"iconUrl":"http://storage.googleapis.com/site-assets/u7dFSjq8MbNv7f_wAXjQwOc06y1w_fY50rdYAxg_KV0_icon-14841ba5294","visualUrl":"http://storage.googleapis.com/site-assets/u7dFSjq8MbNv7f_wAXjQwOc06y1w_fY50rdYAxg_KV0_visual","coverUrl":"http://storage.googleapis.com/site-assets/u7dFSjq8MbNv7f_wAXjQwOc06y1w_fY50rdYAxg_KV0_cover","coverColor":"EBEBEB"}

{
    "subscribers": 204,
}

//feedlyの購読者数取得
function get_feedly_count(){
  $feed_url = rawurlencode( get_bloginfo( 'rss2_url' ) );
  $res = '0';
  $subscribers = wp_remote_get( "http://cloud.feedly.com/v3/feeds/feed%2F$feed_url" );
  if (!is_wp_error( $subscribers ) && $subscribers["response"]["code"] === 200) {
    $subscribers = json_decode( $subscribers['body'] );
    $subscribers = $subscribers->subscribers;
    
    set_transient( 'feedly_subscribers', $subscribers, 60 * 60 * 12 );
    $res = ($subscribers ? $subscribers : '0');
    return $res;
  }
}

//チェックするフィードのURL
$url = "https://nelog.jp/feed";

//データを取得
$json = @file_get_contents("http://cloud.feedly.com/v3/feeds/feed%2F".rawurlencode($url));

//JSONデータを連想配列に変換
$array = json_decode($json,true);

//データが存在しない場合は0扱い
if(!isset($array['subscribers'])){
  $count = 0;
}else{
  $count = $array['subscribers'];
}

<?php

//チェックするフィードURL
$feed = 'https://nelog.jp/feed';
//URLエンコードをする
$feed = rawurlencode($feed);
//フィードのデータを取得
$json = @file_get_contents("http://cloud.feedly.com/v3/feeds/feed%2F{$feed}");
$obj = json_decode($json,true);
//登録者数が0の場合
if(isset($obj['subscribers'])){
  $count = $obj['subscribers'];
}else{
  $count = 0;
}
//チャンネル登録者数を出力
echo $count;

<script>
//feedlyの購読者数を取得
function get_social_count_feedly(rss_url, selcter) {
  jQuery.ajax({
    type: "get", dataType: "json",
    url: "http://query.yahooapis.com/v1/public/yql",
    data: {
      q: "SELECT content FROM data.headers WHERE url='http://cloud.feedly.com/v3/feeds/feed%2F" + encodeURIComponent(rss_url) + "' and ua='#Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.154 Safari/537.36'",
      format: "json",
      env: "http://datatables.org/alltables.env"
    },
    success: function (data) {
      count = data.query.results.resources.content.json['subscribers'];
      //console.log(count);

      jQuery( selcter ).text(count);
    }
  });
}

jQuery(function(){
  get_social_count_feedly('[フィードのURL]', '.feedly-count');
  //get_social_count_feedly('<?php bloginfo("rss2_url"); ?>', '.feedly-count');//Wordpressを使用する場合
});
</script>

get_social_count_feedly('<?php bloginfo("rss2_url"); ?>', '.feedly-count');

<span class="feedly-count">0</span>

<i class="fa fa-spinner fa-spin"></i>