来自外部来源的缩略图不会出现在随机帖子小工具中

由于图像是外部托管的，因此它不会出现在提要的media$thumbnail字段中。我们必须解析帖子的HTML内容来提取图像的URL。需要做两项更改才能实现这一点-

首先从summary提要切换到default提要URL。这对于获取帖子的HTML内容是必要的（summary提要只包含帖子的有限摘要文本，而不是完整的HTML）。更改的每个实例

/feeds/posts/summary?alt=json-in-script

至

/feeds/posts/default?alt=json-in-script

其次，改变从中找到帖子中图像的条件

img = ("media$thumbnail" in entry[i]) ? entry[i].media$thumbnail.url.replace(/'/s[0-9]+(-c)?/, "/s72-c") : noImageUrl;

至

if ("media$thumbnail" in entry[i]) {
  img = entry[i].media$thumbnail.url.replace(/'/s[0-9]+(-c)?/, "/s72-c");
} else if (entry[i].content.$t.match(/'<img.+src'=(?:'"|'')(.+?)(?:'"|'')(?:.+?)'>/)) {
  img = entry[i].content.$t.match(/'<img.+src'=(?:'"|'')(.+?)(?:'"|'')(?:.+?)'>/)[1];
} else {
  img = noImageUrl;
}

请参阅下面的工作示例-

// Feed configuration
var homePage = 'http://video-testing-tahir.blogspot.com',
  maxResults = 4,
  summaryLength = 170,
  noImageUrl = 'http://3.bp.blogspot.com/-vpCFysMEZys/UOEhSGjkfnI/AAAAAAAAFwY/h1wuA5kfEhg/s72-c/grey.png',
  containerId = 'random-post-container';
// Function to generate random number limited from `min` to `max`
// Used to create a valid and safe random feed `start-index`
function getRandomInt(min, max) {
  return Math.floor(Math.random() * (max - min + 1)) + min;
}
// Function to shuffle arrays
// Used to randomize order of the generated JSON feed
function shuffleArray(arr) {
  var i = arr.length,
    j, temp;
  if (i === 0) return false;
  while (--i) {
    j = Math.floor(Math.random() * (i + 1));
    temp = arr[i];
    arr[i] = arr[j];
    arr[j] = temp;
  }
  return arr;
}
// Get a random start index
function createRandomPostsStartIndex(json) {
  var startIndex = getRandomInt(1, (json.feed.openSearch$totalResults.$t - maxResults));
  if (window.console && window.console.log) console.log('Get the post feed start from ' + startIndex + ' until ' + (startIndex + maxResults));
  // document .write('<scr' + 'ipt src="' + homePage + '/feeds/posts/summary?alt=json-in-script&orderby=updated&start-index=' + startIndex + '&max-results=' + maxResults + '&callback=randomPosts"></scr' + 'ipt>');
  add_script(homePage + '/feeds/posts/default?alt=json-in-script&orderby=updated&start-index=' + startIndex + '&max-results=' + maxResults + '&callback=randomPosts');
}
// Widget's main function
function randomPosts(json) {
  var link, summary, img,
    ct = document.getElementById(containerId),
    entry = shuffleArray(json.feed.entry),
    skeleton = "<ul>";
  for (var i = 0, len = entry.length; i < len; i++) {
    summary = ("content" in entry[i]) ? (entry[i].content.$t.replace(/<.*?>/g, "")).substring(0, summaryLength) + '&hellip;' : "";
    if ("media$thumbnail" in entry[i]) {
      img = entry[i].media$thumbnail.url.replace(/'/s[0-9]+(-c)?/, "/s72-c");
    } else if (entry[i].content.$t.match(/'<img.+src'=(?:'"|'')(.+?)(?:'"|'')(?:.+?)'>/)) {
      img = entry[i].content.$t.match(/'<img.+src'=(?:'"|'')(.+?)(?:'"|'')(?:.+?)'>/)[1];
    } else {
      img = noImageUrl;
    }
    for (var j = 0, jen = entry[i].link.length; j < jen; j++) {
      link = (entry[i].link[j].rel == "alternate") ? entry[i].link[j].href : '#';
    }
    skeleton += '<li>';
    skeleton += '<img src="' + img + '" alt="" width="72" height="72">';
    skeleton += '<a href="' + link + '">' + entry[i].title.$t + '</a><br>';
    skeleton += '<span>' + summary + '</span>';
    // Show all post labels ...
    skeleton += ' <small>';
    var tags = entry[i].category,
      labels = [];
    for (var z = 0, zen = tags.length; z < zen; ++z) {
      labels.push('<a href="' + homePage + '/search/label/' + encodeURIComponent(tags[z].term) + '?max-results=20" rel="tag">' + tags[z].term + '</a>');
    }
    skeleton += labels.join(', ');
    skeleton += '</small>';
    skeleton += '<span class="clear"></span></li>';
  }
  ct.innerHTML = skeleton + '</ul>';
}
// document .write('<scr' + 'ipt src="' + homePage + '/feeds/posts/summary?alt=json-in-script&max-results=0&callback=createRandomPostsStartIndex"></scr' + 'ipt>');
add_script(homePage + '/feeds/posts/summary?alt=json-in-script&max-results=0&callback=createRandomPostsStartIndex');
/**
 * `document[dot]write` is disallowed in JSFiddle envioriment and might break your fiddle.
 */
function add_script(url) {
  var s = document.createElement('script');
  s.src = url;
  document.getElementsByTagName('head')[0].appendChild(s);
}

body {
  margin: 0;
  padding: 50px;
  background-color: white;
  font: normal normal 11px/1.4 Arial, Sans-Serif;
  color: black;
}
#random-post-container {
  width: 400px
}
#random-post-container ul,
#random-post-container li {
  margin: 0;
  padding: 0;
  list-style: none;
  overflow: hidden;
}
#random-post-container img {
  display: block;
  float: left;
  border: 1px solid;
  margin: 2px 7px 5px 0;
}
#random-post-container a {
  font-weight: bold;
  font-size: 110%;
}
#rancom-post-container .clear {
  display: block;
  clear: both;
}

<h2>Random Post</h2>
<div id='random-post-container'>Memuat&hellip;</div>