How to use

callback

function

in

lodash

payloads.forEach((payload, index) => {
    getDb(user).update({id: payload.id}, {$set: {data: payload.data}}, {upsert: true}, (err, docs) => {
     docsResponse.push(docs);
     if (index + 1 === payloads.length) {
      if (err) {
       callback(null, err);
       return;
      }
      callback(docsResponse);
     }
    });
   });

function callApi( method, callback = _.noop ) {
  // Wraps a call to an external API, the results of which are for local consumption and -not- stored in redux
  // Used to alert the app when a call begins and ends, and used here as a way of knowing when to show and hide a wait spinner

  // Only requirement here is that <method> returns a Promise when called

  return function( dispatch ) {
    dispatch( { type: ActionTypes.BEGIN_API_CALL } )
    return method()
      .then( ( res ) => {
        dispatch( { type: ActionTypes.END_API_CALL } )
        callback( null, res )
      } )
      .catch( ( err ) => {
        dispatch( { type: ActionTypes.END_API_CALL } )
        callback( err )
      } )
  }
}