How to persist data about current file - RadUploadHandler

[Patrice VIALOR]

Hi,

I'm working on the RadUploadHandler. 
ATM, I have implemented a custom Filename calculation, and folder management following the posts in this forum.

But now, I'm facing another problem :
For a single file, It seem that each time a new chunk of the current file is being uploaded, a new instance of RadUploadHandler is being instantiated.

I'm working on a server-side post-transfer file comparaison, in order to recognize file already uploaded.
From my app point of view, I need to store a same image multiple times (in my DB at least).

So in order to avoir storing the same image N times on the hard drive, I have implemented a post-transfert file-content comparison.

In case of a file upload of an already existing file, this is my scenarion :
- In an overloaded InitializeChunkStorage, based on the filename, I move a possible "identical file" to another filename. At this moment, I want to store multiple informations.
- in an overloaded SaveChunkData, I want to compare the two files (byte to byte comparison), and retrieve the informations stored in the InitializeChunkStorage method.

My problem is, that any information sotred in a CustomRadUploadHandler have disappeared when  I'm in SaveChunkData.

So is there a way to persist informations, in a per-File scope ? (not in a per-upload session).

Thanks in advance.

[Patrice VIALOR]

The only solution I found is to store informations with 

public  override void ProcessRequest(System.Web.HttpContext context)
{
context.Session["persistance_test"] = "mydata";
}

BUT two questions still remain :

1) For a single file, the "normal" scenario for the RadUploadHandler is : receive the upload call, start with the firsts chunks, then continue the remaining chunks, then the final one, and then close the file.

Does this scenario can change ? (Does the order of the actions in the above scenario depends on the order of the received TCP packets - and can change if some TCP packet is dropped -, or can I assert that this order will ever be respected ?)

2) If I put the following session state parameters in my webconfig :

<sessionState mode="InProc" cookieless="true" timeout="2" />  (Session timeout = 2 minutes)

In the following cases, does the timeout (the sessionEnd event precisely) will be throwed before the end of the upload :
- If I upload multiple files, and the total upload time is estimated above 2 minutes ?
- If I upload a single file, and the total upload time is estimated above 2 minutes ?


Thanks in advance.

[Alex Fidanov]

Hi Raphaël,

The RadUploadHandler should not receive another chunk, if the previous one was not successfully saved. The RadUpload should send only consecutive chunks to the handler. I am not sure I understood your second question correctly. Could you please elaborate more on the session time out issue?

Best wishes,
Alex Fidanov
the Telerik team

[Patrice VIALOR]

About session time out, I found that the timeout calculated is between consecutives HttpHandler calls.
So the timeout will not be throwed during an upload.

Thanks