iOS-JavaScript sharing data full example

iOS-javascript-sharing-data-full-example.js

/**
 * Having imported:
 *
 * bluebird.min.js
 * rx.js
 */

// Business Logic
async function doStuff() {
  // Get query from user
  let query = await someModalWillReturnThis();

  // Load data from DB
  let data = await fetchDataFromDatabase(query);

  // Show results to user
  UI.update(data);
}

function fetchDataFromDatabase(query) {
  
  // Calling iOS method here
   location.href = `app://loadStuff`
  
  // Returning the Promise
  return new Promise((resolve, reject) => {
    
    // Timeout and reject.
    let timeout = setTimeout(() => reject(new Error('Timeout')), 3000);

    // Observing the call to the callback
    Rx
      .Observable
      .create(function subscribe(observer) {
        // This will be called by the iOS client
        didReceiveDataFromDatabase = function(data) {
          // Parse, process your data if needed.
          observer.next(JSON.parse(data));
        }
      })
      .subscribe(result => {
        // Receiving data here, resolving promise
        clearTimeout(timeout)
        resolve(result);
      });
  });  
}

// We declare this as the default action.
function didReceiveDataFromDatabase(data) {
  console.log('didReceiveDataFromDatabase', data);
}