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JavaScript Asynchronous Programming with JavaScript Understanding Promises Handle Multiple Promises with Promise.all

Amy Preci
Amy Preci
6,247 Points

Wiki links return 404, no page exists for some names in the JSON data. Therefore getting rejected promises, how to fix?

Is there a way that once the Promise is rejected, to kick it out of the json data or to kick it out of the profiles array? Otherwise the astronaut's name is being appended to the wiki URL, but that url doesn't exist. So none of my astronauts render on the page. Has anyone found a fix?

function getJSON(url) { return new Promise((resolve, reject) => { const xhr = new XMLHttpRequest(); xhr.open('GET', url); xhr.onload = () => { if(xhr.status === 200) { let data = JSON.parse(xhr.responseText); console.log(data); resolve(data); } else { reject( Error(xhr.statusText) ); } }; xhr.onerror = () => reject( Error('A network error occurred.') ); xhr.send(); });

}

function getProfiles(json) { const profiles = json.people.map( person => { return getJSON(wikiUrl + person.name); });

return Promise.all(profiles); }

1 Answer

Steven Parker
Steven Parker
231,172 Points

This is generally the result of different spellings in the translation of foreign names, and has come up several times, as you can see in the Questions section of this video page.

A sample of previous questions and answers about this issue include: