Transferring files/large data blocks
deepone
Member ✭
in Help Center
I would like to be able to pass (potentially large) files between a server and client using ice... I've tried using sequence<byte> and it worked just fine at first but when the files got to a few Mbs things stopped working... (I got an unknown exception from the remote operation)
My setup is something like this:
sequence<byte> ByteData;
interface Client {
void uploadFile( string filename, ByteData data );
};
interface Server {
void login( Client* cli );
};
// in client
server->login( client );
// in server
void
ServerI::login( ClientPrx client, ..... )
{
// read file data
client->uploadFile( filename, data );
}
---
This works for small files, eg the test file I used first was 71k...
For larger files I get "Unknown exception" in the server and ClientI::uploadFile is never reached on the client...
So, is there a recommended way to do this?
My setup is something like this:
sequence<byte> ByteData;
interface Client {
void uploadFile( string filename, ByteData data );
};
interface Server {
void login( Client* cli );
};
// in client
server->login( client );
// in server
void
ServerI::login( ClientPrx client, ..... )
{
// read file data
client->uploadFile( filename, data );
}
---
This works for small files, eg the test file I used first was 71k...
For larger files I get "Unknown exception" in the server and ClientI::uploadFile is never reached on the client...
So, is there a recommended way to do this?
0
Comments
Something like:
sequence<byte> ByteData;
interface Receiver {
void receive( ByteData data);
void close();
};
interface Server {
Receiver *transfer( string filename);
};
Your client will send multiple chunks of the original file
invoking multiple receive() until EOF.
I have used this approach in Java and it is really ***fast***
(well, ftp is a little bit faster but....you have no objects !!)
You can experience the performances using different chunk size.
64K it is rather good.
Hope it helps,
Guido.
You can increase the max message size by setting the property Ice.MessageSizeMax. The default is 1024, meaning 1024 KB = 1MB. Try setting it to a larger value, like 10240 = 10MB.
For more information, have a look at the description of the MessageSizeMax property in the manual's reference section.
If you would like to see an example for transferring arbitrary long files in "chunks", have a look at the code of IcePatch in src/IcePatch.