Specifies the URL of the server-side proxy that streams the resulting file and enables export in Safari.
Safari does not implement an API for saving files. In this case, the Diagram widget can POST the content to a server-side proxy which streams the file back to the user. To enable this functionality, set the export.proxyUrl option to the proxy.
- Your proxy receives a POST request with the following parameters in the request body: fileName, contentType (the MIME type of the file) and base64 (the base-64 encoded file content).
- The proxy should return the decoded file with the "Content-Disposition" header set to attachment; filename="