Prevent caching of json data

[systemsplanet-zz]

Browsers cache the json returned from a html links

Ideally, Exhibit is using the latest json data.
We can prevent caching by appending a random number:
<link href="senators.json?i=232323.232323" type="application/json" rel="exhibit-data" />

We can generate this HTML dynamically

// create an HTML head link with optional cache buster
function loadExhibitResource(file, opts ){              
  if (opts && opts.cache && opts.cache === 'no')   file += "?i="+(Math.random()*99999999);
  var link  =  document.createElement("link");
  link.href =  file;
  link.type =  'application/json';
  link.rel  =  'exhibit-data';
  document.getElementsByTagName("head")[0].appendChild(link);       
}

loadExhibitResource('senators.json', {cache: no} );

[karger]

This would be great to have but not always---for static exhibits it's going to force lots of wasted fetches. So ideally this would be something you could turn on or off, perhaps by putting a parameter into the link tag e.g. data-ex-cache=false or data-ex-no-cache=true . A pull request would be welcome!

[camilstaps]

For puristic reasons it would be preferable to use Date.now() instead of a random number:

• So that you don't stress the OS's entropy source
• To ensure that the same number does not occur twice

[Bric-e]

Thank you for the trick.
By the way, you need to add quotes to cahe value when calling the method:
loadExhibitResource('senators.json', {cache: 'no'} );