Death on idea: filters on synth bodies

Poul-Henning Kamp phk at
Mon Aug 23 08:57:51 UTC 2021

For the longest times I have wanted to run synth bodies through
VFP, to get rid of the temp VSB and to enable ESI processing
on error messages.

It is not going to happen.

It would become quite a mess in `vcl_synth{}`.

We do not run `vcl_deliver{}` after `vcl_synth{}, so there
both the VFP and VDP filter lists would have to be configured
at the same time, which in addition to requiring two filter
lists variables, makes it near impossible to produce the automatic
proposal for VDP filters based on the object.

But we would also still have to buffer the body in a VSB, because we
"suck" data through VFP from the core code, we dont push it in from
the fetch code.

It would be more feasible to do it in the case of `vcl_backend_error{}`
because we only need to deal with the VFP list there, but the temporary
VSB would still be required there too.

So, yeah:  Not going to happen.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.

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