forceIframeTransport

Set this option to true to force iframe transport uploads, even if the browser is capable of XHR file uploads.
This can be useful for cross-site file uploads, if the Access-Control-Allow-Origin header cannot be set for the server-side upload handler which is required for cross-site XHR file uploads.

• Type: boolean
• Default: false

redirect

Set this option to the location of a redirect url on the origin server (the server that hosts the file upload form), for cross-domain iframe transport uploads. If set, this value is sent as part of the form data to the upload server.
The upload server is supposed to redirect the browser to this url after the upload completes and append the upload information as URL-encoded JSON string to the redirect URL, e.g. by replacing the "%s" character sequence.

• Type: string
• Example: 'http://example.org/cors/result.html?%s'

redirectParamName

The parameter name for the redirect url, sent as part of the form data and set to 'redirect' if this option is empty.

• Type: string
• Example: 'redirect-url'

postMessage

Set this option to the location of a postMessage API on the upload server, to enable cross-domain postMessage transport uploads.

• Type: string
• Example: 'http://example.org/upload/postmessage.html'

Note: This feature is currently only fully supported by Google Chrome.