Question

I have this page where a user can upload documents (multiple documents, size limit 10MB each). It is a two step process. Step 1 has the input form. Step 2 is the preview page with a submit button.

How should I handle the scenario where the user closes the browser while on the preview page, without submitting the form? Should I save the files in a temp location after step 1? Is this a decent solution?

And what are the best practices in general for uploading (reasonably) large files?

Thanks.

Answer 1

You can use a temporary folder to save the files and copy the files to their final location only on submission of the form.

In any case, it would be better to implement a garbage collector. The garbage collector can empty the temporary folder every night. But when using a garbage collector, if you have a way to identify files that were not submitted (for example, if a row is added to a database upon submission), you can put the files in their final location from the beginning, and let the garbage collector remove them every night.

Upload of large files can be done using a JQuery UI plugin such as Uploadify: http://www.uploadify.com/.
You should pay attention that it uses flash, which on the one hand is very good for uploading large files, but on the other hand it will prevent your application from supporting Apple machines such as iPad.