Re: [hybi] Reliable message delivery (was Re: Technical feedback.)

Jamie Lokier <jamie@shareable.org> Wed, 03 February 2010 00:56 UTC

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Date: Wed, 03 Feb 2010 00:56:50 +0000
From: Jamie Lokier <jamie@shareable.org>
To: Ian Hickson <ian@hixie.ch>
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Cc: Hybi <hybi@ietf.org>
Subject: Re: [hybi] Reliable message delivery (was Re: Technical feedback.)
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Ian Hickson wrote:
> On Mon, 1 Feb 2010, Maciej Stachowiak wrote:
> > On Feb 1, 2010, at 4:00 PM, Ian Hickson wrote:
> > > 
> > > On the client side, I agree in principle (at least to ensure that no 
> > > client-to-server data is lost in a case where the API is used to send 
> > > frames then immediately close the connection). However, what if the 
> > > server never closes its side of the connection, even after the client 
> > > initiates a close? Should we have some sort of timeout?
> > > 
> > > On the server side, I don't think there's any point _requiring_ that 
> > > the server close gracefully. If the server really doesn't care if data 
> > > it just sent is received, e.g. because it knows the client side has 
> > > already GC'ed its WebSocket object, then it should just be able to 
> > > close abruptly.
> > 
> > How can the server possibly know that the client has already GC'd its 
> > WebSocket object, if the server and not the client is the initiator of 
> > the close? (If the client initiates the close, then at least in my 
> > proposal there's no extra work for the server.)
> 
> The server and the client are typically written by the same person. If the 
> client sends a message in the subprotocol saying "ok after this I'm 
> throwing away all references to the object", then the server can know that 
> there's no point sending further data.

Isn't that the same as a close message with the same semantics?

-- Jamie