En primer lugar, quiero que cada iteración asigne y obtenga todos los valores de title , desc y adref presentes en mi jList y un segundo paso, en el hecho de que adref son caracteres de cadena únicos, quiero comparar cada valor "adref" si ya está presente en DB o no.

 const jList = []; var array = jList; var arrayLength = Object.keys(array).length for(var i = 0; i <= arrayLength; i++) { var title = array.data[i].title; var desc = array.data[i].description; var adref = array.data[i].adref; const adrefExists = await ColectData.exists({ adref: adref }); if (adrefExists === 'undefined' || adrefExists === true) console.log("adref exists"); continue; else: console.log( "adding" + title + " " + desc + " " + adref + "on DB..."); assignDataValue(title, desc, adref) continue; }

pero tengo esto:

 0 (node:7434) UnhandledPromiseRejectionWarning: TypeError: Cannot read property '0' of undefined at apiToDB (/Users/mac/Desktop/project_test/index.js:59:28) at /Users/mac/Desktop/project_test/index.js:78:1 at Layer.handle [as handle_request] (Use `node --trace-warnings ...` to show where the warning was created) (node:7434) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1) (node:7434) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Gracias