How does one chunk files using actionscript (flex)?

Question

I am doing file transfers, but the filereference API doesn't support file chunking. Has anyone done this before? For example, I would like to be able to upload a 1 gig file from an AIR client to a custom PHP/Java/etc. service.

Answer 1

It seems that all you should have to do is use the upload() routine. The php or java service should be doing the chunking.

var myHugeFile = new air.File('myHugeLocal.file');
myHugeFile.upload(new URLRequest("http://your.website.com/uploadchunker.php"));

There is a much more elaborate example of using filereference in the adobe learning area here: http://www.adobe.com/devnet/air/flex/articles/uploading_air_app_to_server.html

Answer 2

Three options jump out on this:

1. Use an FTP service that supports resumable transfers, assuming flash supports this as well. Maybe not an option if you are wanting to communicate with a custom service of your own.
2. Leverage the http file part header support. Only applicable if AIR allows access to the appropriate http headers (content-range & content-length). This is what BITS does. Probably a bit harder to implement.
3. Hand roll your own TCP or UDP protocol exchange. Not for the faint of heart. I'd look in the OSS space before going this route.