JavaScript fetch()

by

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const button = document.querySelector('.js-button');
 
const output = document.querySelector('.js-output');
 
 
 
async function getRandomPost() {
 
  try {
 
    const response = await fetch('https://jsonplaceholder.typicode.com/posts');
 
    const posts = await response.json();
 
    const randomIndex = Math.floor(Math.random() * posts.length);
 
    const randomPost = posts[randomIndex];
 
    output.textContent = randomPost.body;
 
  } catch (error) {
 
    console.error('Error fetching data:', error);
 
  }
 
}
 
 
 
document.addEventListener("DOMContentLoaded", async function() {
 
  await getRandomPost();
 
});
 
 
 
button.addEventListener('click', async function() {
 
  await getRandomPost();
 
});

html:

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<button class="js-button">Get random post</button>
 
<div class="js-output"></div>

Fetch params:

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const fetchData = (url, userOptions = {}) => {
 
    const defaultOptions = {
 
        method: 'POST',
 
        credentials: 'same-origin',
 
        cache: 'no-cache',
 
        headers: {
 
            'Content-Type': 'application/json',
 
            'LoginToken': 'l0g1n-t0k3n'
 
        }
 
    };
 
    // const options = jQuery.extend(defaultOptions, userOptions);
 
    const options = Object.assign({}, defaultOptions, userOptions);
 
    return fetch(url, options);
 
};
 
 
 
// Usage
 
fetchData(url)
 
    .then(response => response.json())
 
    .then(response => {
 
        console.log(response);
 
    })
 
    .catch(error => console.error('Error: ', error));
 
 
 
fetchData(url, {method: 'GET'})
 
    .then((response) => {
 
        return response.text();
 
    })
 
    .then(response => {
 
        let $responseContent = $(response).find('.content').html();
 
        $('.content').html($responseContent);
 
    })
 
    .catch(error => console.error('Error: ', error));

All fetch() parameters:

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return fetch(url, {
 
        method: "POST", // *GET, POST, PUT, DELETE, etc.
 
        mode: "cors", // no-cors, cors, *same-origin
 
        cache: "no-cache", // *default, no-cache, reload, force-cache, only-if-cached
 
        credentials: "same-origin", // include, same-origin, *omit
 
        headers: {
 
            "Content-Type": "application/json; charset=utf-8",
 
            // "Content-Type": "application/x-www-form-urlencoded",
 
        },
 
        redirect: "follow", // manual, *follow, error
 
        referrer: "no-referrer", // no-referrer, *client
 
        body: JSON.stringify(data), // body data type must match "Content-Type" header
 
    })

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