Sending Message Objects via TCP/IP

[GotRobotFriends]

Hi all,

Forgive me if I'm rehashing old ground, my search of the forum didn't turn up anything concrete so I thought I'd ask here. What's the best way to send Message objects over a TCP/IP connection, I'm assuming that you would flatten to XML, can you then link the xml string directly into the TCP write? (I've only ever used flatten to string). Will inheritance be maintained through the flattening operation? That is to say, if I send some message (not the generic "Message object), I unflatten from XML passing in only the generic "Message" object to the type terminal, will the resulting wire carry the child message? Or will I get a casting error?

If it doesn't contain the child, then I have to handle the cast some other way, perhaps by writing a header which is then read as input to a case structure to make the correct unflatten?

Does anyone have any experience with this problem?

Thanks in advance!

[komorbela]

Once AQ asked for examples to help the development of Network Actors. You can find it in this post. Maybe you could add your use case as another useful example to that post. By the way I haven't thought about it as I don't need it now. I am just hoping to get it and use it smoothly if I ever will need it

[drjdpowell]

Why XML?   Just Flatten to String and unflatten at the other end.  Handles child-class objects no problem (the name of the class is part of the flattened string).

[justACS]

As drjdpowell said, I would suggest just using Flatten to String.  It's less verbose and works well.  And yes, if you unflatten using the generic message, the specific message type will be preserved.

[GotRobotFriends]

Hi JD,

For some reason I was under the impression that XML was required to handle the class information. I did some tests and know that XML maintains that Message's payload (say I want to send a message that carries a double). Is this still the case with flatten to string (my tests of looking at the flattened output show that something is happening when I change the value of the payload, but it's pretty incomprehensible).

Thanks for the info guys.

[David_Staab]

As niACS said, Flatten To String serializes the object properly, and Unflatten From String recovers it fully. Use it.

If you're interested in serializing objects to non-proprietary formats, check out Aristos Queue's thread on LAVA about making a general-purpose serializer for LVOOP.