I'm trying to implement a Readable stream that emits objects parsed from UDP 
datagrams.  I've been looking for some good stream tutorials, but nothing's 
really clicking for me.  I think this is compounded by the fact that the stream 
documentation on nodejs.org says that Readable.push() and Writable._write() 
both accept Buffers or strings, not referencing the objets that are implied by 
the presence of the objectMode option.

I'm going to be listening on a UDP socket and I want to emit one or more 
objects per dgram message; the message is newline delimited and could have 
multiple events per message.  I then want to use multiple Writable streams to 
distribute the received objects.  I will not be polling for data, obviously; 
there's no read() method appropriate for a datagram.  At a high level, I want 
to be able to do the following:
        var udpListener = new UDPListener(somePort);
        var frameHandler = new FrameHandler();
        var destination = fs.createWritableStream("targetFile.txt");

        udpListener.pipe(frameHandler).pipe(destination);

udpListener should emit objects, frameHandler should be a transformer that 
modifies the object, and destination should accept a string or buffer to be 
written out to a file or over the network to another service.  Under the hood, 
UDPListener will create a dgram socket, split received message by newline, turn 
the message into an object, and then send it downstream.

The way the documentation for _read reads, it implies that I need to maintain 
my own buffer of data received on the UDP socket, which would then be push()'ed 
when _read is invoked.  I would have thought that I'd just be able to 
arbitrarily push() new data, but push()'ing an object results in "[Object 
object]" being received at the next phase of the pipeline.

Is an invocation _read() supposed to result in one or more calls to push() by 
the implementing class?  How do I push() an object?

Thanks,
Brian

--
Brian Lalor
bla...@bravo5.org
http://github.com/blalor

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