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JavaScript Manage Multiple Requests with Promise.all

Homero Mendoza
Homero Mendoza
12,374 Points

Uncaught (in promise) TypeError: data.map

have this error when adding the Promise.all

Uncaught (in promise) TypeError: data.map is not a function at generateOptions (app.js:46:22) at app.js:26:1

const select = document.getElementById('breeds');
const card = document.querySelector('.card'); 
const form = document.querySelector('form');

// ------------------------------------------
//  FETCH FUNCTIONS
// ------------------------------------------
// function use to make code better an fetch with json
function fetchData(url){
  return fetch(url)
  .then(checkStatus)
  .then(res => res.json())
  .catch(error => console.log('looks like there was a problem', error) )
}


//fetch the img api
Promise.all([
fetchData('https://dog.ceo/api/breeds/image/random'),
fetchData('https://dog.ceo/api/breeds/list')
])
.then(data => {
const breedList = data[0].message;
const randomImage = data[1].message;

generateOptions(breedList);
generateImage(randomImage)

});



// ------------------------------------------
//  HELPER FUNCTIONS
// ------------------------------------------
function checkStatus(response){
  if (response.ok){
    return Promise.resolve(response);
  }else {
    return Promise.reject(new Error(response.statusText));
  }
}


function generateOptions(data){
const options = data.map(item => `
<option value ='${item}'>${item}</option>
`).join('');
  select.innerHTML = options;
}



function generateImage(data){
const html=  `  
<img src ='${data}' alt>
<p>Click to view images of ${select.value}s</p>` ;
card.innerHTML = html;

}

function fetchBreedImage(){
const breed = select.value;
const img = card.querySelector('img');
const p = card.querySelector('p');

  fetchData(`https://dog.ceo/api/breed/${breed}/images/random`)
  .then(data => {
  img.src = data.message;
    img.alt = breed;
    p.textContent = `Click to view more ${breed}s`;
  })
}


// ------------------------------------------
//  EVENT LISTENERS
// ------------------------------------------

select.addEventListener('change', fetchBreedImage);
card.addEventListener('click', fetchBreedImage);

// ------------------------------------------
//  POST DATA
// ------------------------------------------

1 Answer

Steven Parker
Steven Parker
229,732 Points

The index values for breedList and randomImage are reversed. The breedList should be made from data[1], and randomImage from data[0].

Or, you could change the order of the fetchData calls.