Re: [quicwg/base-drafts] Make HTTP frames a TLV format. This has several advantages: (#2235)

ianswett <notifications@github.com> Mon, 24 December 2018 18:42 UTC

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Subject: Re: [quicwg/base-drafts] Make HTTP frames a TLV format. This has several advantages: (#2235)
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After thinking about this more, I think this is a very important change and making it will cause HTTP/3 align better with the QUIC transport.

In retrospect, PR#2098(Allow DATA to extend to the end of the stream) violated what appears to be a core design choice of HTTP/2, that all frames explicitly specify a length, so they're easily skippable.  Admittedly, skipping DATA doesn't make much sense, but it is still inconsistent.

To me, that's one of many signals that TLV is a better approach.  I was intending to create an extension that was DATA without length, but I realized that this new frame type would have a length byte, but it would be ignored or specified as a particular incorrect value(ie: 0), neither of which are ideal.

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