VIP14: *.body access

Synopsis

Plan for VCL access/manipulation of *.body and VMOD filter insertion

So for instance synthetic objects can be gzip'ed or ESI'ed, but without overworking the workspaces.

The list of filters to be applied is turned into a list of filter names, something like:

req.filters = "gunzip esi gzip"

VCL can edit this list, for instance with regsub() to insert VMOD filters

A special class of VCL functions can stuff things into the filter pipelines:

sub vcl_foobar {
    body += "<HTML>"
    body += "<H1>" + req.http.foobar + "</H1>"
    ...
}

The vcl_error{} and vcl_synthetic{} functions set up the HTTP headers, configure the filter list and designate the function to fill out the body:

sub vcl_synthetic {
    ...
    return (deliver(vcl_foobar));
}