Error Recovery
Handle upload errors gracefully. Show user-friendly messages and offer retry options for failed uploads.
What you should see: failures are collected into a panel you can retry from, rather than losing the whole queue. Exceed the 10 MB cap to produce a failure and watch the recovery path.
var uploader = CoreUpload.create('#error-uploader', {
uploadUrl: '/api/upload/upload',
multiple: true,
autoUpload: true,
maxFileSize: '10MB',
onTaskError: function(file, error) {
showError(file.name, error); // Add to the failed-uploads panel
},
onTaskComplete: function(file, response) {
clearError(file.name); // Remove from the panel after a successful retry
}
});
document.getElementById('btn-retry-all').onclick = function() {
uploader.retry(); // Retry all failed uploads
};Retries happen without you
Transient failures are retried automatically with a backoff, so most network hiccups resolve without the user ever seeing them. The error callbacks are how you observe that it happened at all.
What to do when the retries run out
Automatic retries only cover the transient case. Once they are exhausted the file needs a manual retry the user can reach, and a message that distinguishes causes: a network problem is worth trying again, a file the server refused is not. Offering “retry” on a permanent rejection just reproduces the failure more slowly.