how to download file in react js

Question

I receive file url as response from api. when user clicks on download button, the file should be downloaded without opening file preview in a new tab. How to achieve this in

Answer 1

tldr; fetch the file from the url, store it as a local Blob, inject a link element into the DOM, and click it to download the Blob

I had a PDF file that was stored in S3 behind a Cloudfront URL. I wanted the user to be able to click a button and immediately initiate a download without popping open a new tab with a PDF preview. Generally, if a file is hosted at a URL that has a different domain that the site the user is currently on, immediate downloads are blocked by many browsers for user security reasons. If you use this solution, do not initiate the file download unless a user clicks on a button to intentionally download.

In order to get by this, I needed to fetch the file from the URL getting around any CORS policies to save a local Blob that would then be the source of the downloaded file. In the code below, make sure you swap in your own fileURL, Content-Type, and FileName.

fetch('https://cors-anywhere.herokuapp.com/' + fileURL, {
    method: 'GET',
    headers: {
      'Content-Type': 'application/pdf',
    },
  })
  .then((response) => response.blob())
  .then((blob) => {
    // Create blob link to download
    const url = window.URL.createObjectURL(
      new Blob([blob]),
    );
    const link = document.createElement('a');
    link.href = url;
    link.setAttribute(
      'download',
      `FileName.pdf`,
    );

    // Append to html link element page
    document.body.appendChild(link);

    // Start download
    link.click();

    // Clean up and remove the link
    link.parentNode.removeChild(link);
  });

This solution references solutions to getting a blob from a URL and using a CORS proxy.