fetch errors code example

Example 1: javascript fetch api

fetch('http://example.com/movies.json')
  .then((response) => {
    return response.json();
  })
  .then((data) => {
    console.log(data);
  });

Example 2: how to handle fetch errors

function CheckError(response) {
  if (response.status >= 200 && response.status <= 299) {
    return response.json();
  } else {
    throw Error(response.statusText);
  }
}

// Now call the function inside fetch promise resolver
fetch(url)
  .then(CheckError)
  .then((jsonResponse) => {
  }).catch((error) => {
  });

Example 3: js fetch api

// Example POST method implementation:
async function postData(url = '', data = {}) {
  // Default options are marked with *
  const response = await 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'
      // 'Content-Type': 'application/x-www-form-urlencoded',
    },
    redirect: 'follow', // manual, *follow, error
    referrerPolicy: 'no-referrer', // no-referrer, *no-referrer-when-downgrade, origin, origin-when-cross-origin, same-origin, strict-origin, strict-origin-when-cross-origin, unsafe-url
    body: JSON.stringify(data) // body data type must match "Content-Type" header
  });
  return response.json(); // parses JSON response into native JavaScript objects
}

postData('https://example.com/answer', { answer: 42 })
  .then(data => {
    console.log(data); // JSON data parsed by `data.json()` call
  });

Example 4: .fetch method

fetch('http://example.com/movies.json')
  .then(response => response.json())
  .then(data => console.log(data));

Example 5: how to handle fetch errors

const response = await fetch(url);
if (response.status >= 200 && response.status <= 299) {
  const jsonResponse = await response.json();
  console.log(jsonResponse);
} else {
  // Handle errors
  console.log(response.status, response.statusText);
}

Example 6: fetch error handling js

export async function getStaticProps(context) {
  const res = await fetch(`https://...`)
  const data = await res.json()

  //use this statement for the program not to crush but go back to the home page
  if (!data) {
    return {
      redirect: {
        destination: '/',
        permanent: false,
      },
    }
  }

  return {
    props: {}, // will be passed to the page component as props
  }
}