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JavaScript Asynchronous Programming with JavaScript Understanding Promises Using Fetch

Gavin Eyquem
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Gavin Eyquem
Front End Web Development Techdegree Student 20,496 Points

TypeError: person.thumbnail is undefined.

I try to make sure the code is as shown in the video, but when I run the code I get the above error. It then points to line 73 in the JS file.

Can someone tell me what I'm missing?

Here's my code... function getProfiles(json) { const profiles = json.people.map( person => { return fetch(wikiUrl + person.name) .then(response => response.json()) }); return Promise.all(profiles); }

// Generate the markup for each profile function generateHTML(data) { data.forEach(person => { const section = document.createElement('section'); peopleList.appendChild(section);

// Check if request returns a 'standard' page from Wiki if (person.type === 'standard') { section.innerHTML = <img src=${person.thumbnail.source}> <h2>${person.title}</h2> <p>${person.description}</p> <p>${person.extract}</p> ; } else { section.innerHTML = <img src="img/profile.jpg" alt="ocean clouds seen from space"> <h2>${person.title}</h2> <p>Results unavailable for ${person.title}</p> ${person.extract_html} ; } }); }

btn.addEventListener('click', (event) => { event.target.textContent = "Loading...";

fetch(astrosUrl) .then(response => response.json()) .then(getProfiles) .then(generateHTML) .catch(err => { peopleList.innerHTML = '<h3>Something went wrong!</h3>'; console.log(err); }) .finally( () => event.target.remove()) });

Steven Parker
Steven Parker
231,236 Points

Gavin Eyquem — A much better way to show what you are doing in a workspace is with a snapshot, which allows us to easily try out the code. Here's a video about making and sharing a snapshot.

You may also want to take a look at this video about Posting a Question.