File picker

acceptAttribute() returns the value for an <input type="file"> accept attribute, built from the same list the server checks against:

import { acceptAttribute } from 'upload-safety';

<input type="file" name="file" accept={ acceptAttribute( [ 'pdf', 'docx' ] ) } />

Without an argument it lists every supported extension.

Note

accept only filters the dialog. Users can switch it to “All files”, and scripts can post anything. The server check is the one that counts.

The package entry imports node:zlib and node:crypto. If your bundler refuses those in client code, call acceptAttribute() on the server and pass the string down, or copy the value into a constant.