Attempting to fetch a spreadsheet via Angular from an external URL triggers a CORS error. How can I resolve this?
function retrieveDataSheet() {
const sheetUrl = 'https://example.com/sample.xlsx';
fetch(sheetUrl)
.then(response => response.arrayBuffer())
.then(buffer => {
const workbook = XLSX.read(buffer, { type: 'array' });
const firstSheetName = workbook.SheetNames[0];
const firstSheet = workbook.Sheets[firstSheetName];
console.log('Parsed data:', XLSX.utils.sheet_to_json(firstSheet));
})
.catch(err => console.error('Fetch failed:', err));
}
The error is due to the external server not setting the necessary CORS headers. In my experience, routing the request through a backend proxy is often the best approach. This proxy fetches the spreadsheet, then forwards the data to your Angular application while handling CORS on the server side. It is also worth discussing with the external service provider about enabling proper CORS headers if that is feasible, as this could be a more sustainable solution for production environments.
hey, try adding a cors-anywhere proxy before your url. e.g. prepend ‘https://cors-anywhere.herokuapp.com/’ for testing. not ideal for prod tho, so look into a more permanent fix later
hey, u might consider a serverless proxy solution. i used a lambda function to fetch and return the sheet, bypassing cors on client side. ever tried a similar approach? curious how it compared to traditional backends in your experience.