The ouput is exactly the same as before:

```
   "previews" : [
      {
         "resource_uri" : null,
         "filetype" : "image/png",
         "image_url" : "https://marketplace.cdn.mozilla.net/img/uploads/previews/full/90/90318.png?modified=1361093178",
         "thumbnail_url" : "https://marketplace.cdn.mozilla.net/img/uploads/previews/thumbs/90/90318.png?modified=1361093178",
         "id" : 90318
      },
    ]
```

What changes is that internally, in ES, we don't generate and store the URL at index time. Instead, we store what we need to generate it when we do through `es_app_to_dict`. So there is no external change, except that now, we can change the base URL for dynamic media. So someone requesting this app from our regular servers would get the above ouput, and someone requesting it through our china servers, which have a different base URL set for dynamic media, would get something like:
```
   "previews" : [
      {
         "resource_uri" : null,
         "filetype" : "image/png",
         "image_url" : "https://marketplace.cdn.mozilla.net.cn/img/uploads/previews/full/90/90318.png?modified=1361093178",
         "thumbnail_url" : "https://marketplace.cdn.mozilla.net.cn/img/uploads/previews/thumbs/90/90318.png?modified=1361093178",
         "id" : 90318
      },
    ]
```

Or whatever the CDN URL is for China.