Send a file

Send a new file to Nextcloud and return the fileId used to create a signature request. Files must be uploaded as multipart/form-data with field name 'file[]' or 'files[]'. Note on multiple file uploads: PHP has a limit on the number of files that can be uploaded in a single request (max_file_uploads directive, default 20). When uploading many files (more than 20), consider uploading them sequentially in multiple requests or use individual file uploads like the Files app does.