app/scripts/services/tile-proxy.js
async function json(url, callback, pubSub) {
  // Fritz: What is going on here? Can someone explain?
  if (url.indexOf('hg19') >= 0) {
    await sleep(1);
  }
  // console.log('url:', url);
  return fetchEither(url, callback, 'json', pubSub);
}
async function json(url, callback, pubSub) {
  // Fritz: What is going on here? Can someone explain?
  if (url.indexOf('hg19') >= 0) {
    await sleep(1);
  }
  // console.log('url:', url);
  return fetchEither(url, callback, 'json', pubSub);
}
async function json ( url , callback , pubSub ) { // Fritz: What is going on here? Can someone explain? if ( url . indexOf ( 'hg19' ) >= 0 ) { await sleep ( 1 ) ; } // console.log('url:', url); return fetchEither ( url , callback , 'json' , pubSub ) ; }
Send a JSON request and mark it so that we can tell how many are in flight

@param url: URL to fetch
@param callback: Callback to execute with content from fetch
Send a JSON request and mark it so that we can tell how many are in flight