Inserting a Middle Tier and Blob/File Transfer

[sleonard]

I currently have a 2 tier application which I need to bring into the 21st Century by creating a Middle tier with all the advantages that will bring.

My problem is that some of the access to the storage/persistence layer is via an API which takes a file handle from the client. The API then writes a file from the server to the referenced area on the client.

If I create a DCOM object and place it on the middle tier, what will happen if I pass it a client file handle to be used in the same API call?

I hope that makes sense and hope someone can help.

Stephen ...

 

[palbano]

>> if I pass it a client file handle to be used in the same
>> API call?

if i follow you, that will fail since the file handle was opened on a different machine it will not be valid on the remote machine.

The client will have to stream the file bytes to the server in your new architecture.

-pete

 

[sleonard]

Thanks pete,

I had thought as much but wanted some confirmation before I got stuck into testing it.

I think the problem in my case is streaming the bytes from the server to the client. Can you suggest a method for doing this?

I'm toying with several options, including mapped network drives (Ugly) and socket connections (still not ideal but much nicer).

Thanks again for your comments

Stephen ...

 

[palbano]

what is the client environment - OS, development language/tools?

I have been doing Socket dev since 1994 so for me it's it's usually my first choice. It is just so solid.

-pete

 

[SemperFiDownUnda]

I just left a project where we needed the client on a web browser to upload a file to Domino (Lotus's Web server...YUK) and the Web Server called a COM object on an application server that ultimately put it into a SQL database. Now what we did was to have the client app (in this case the Web server is the client app) read the file into a binary array and pass that Binary array to the COM object's method as a parameter. The method then uploaded the contents of the file to the database.
Benifit of this method is that no "Shared" drive is needed.