Re: [quicwg/base-drafts] HTTP/3 frame encodings are unnecessarily difficult to serialize and parse (#2396)

Lucas Pardue <notifications@github.com> Thu, 31 January 2019 00:16 UTC

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Subject: Re: [quicwg/base-drafts] HTTP/3 frame encodings are unnecessarily difficult to serialize and parse (#2396)
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If we want to do this, we should still mandate that all extension frames
have a length, so endpoints can easily skip over them

On Thu, 31 Jan 2019, 08:42 ianswett <notifications@github.com wrote:

> Multiple HTTP/3 frames have lengths, but do not require the length to
> deserialize.
>
> On the serialization side, those require extra work to determine the size
> before serializing them, which may or may not be easy. SETTINGs is fairly
> complex because it's a series of varints, so you either need to do a
> two-pass serialization or write the SETTINGs and then go back and write the
> length(possibly assuming it's a 2 byte length?).
>
> On the parsing side, extra work is required to verify that the parsed
> length matches the specified length.
>
> This also wastes a byte or two in a few cases.
>
> I suggest we use the principle that if it's easier to serialize and
> deserialize without a frame length then the length should be omitted.
>
> Related to #2395 <https://github.com/quicwg/base-drafts/issues/2395>
>
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