unable to compare two headers in vcl

[hamnis]

sub vcl_fetch {
    if (obj.http.etag ~ req.http.if-none-match) {
      error 304 "Not Modified";
    }
}

causes compile error. Message from VCC-compiler: Expected CSTR got 'req.http.if-none-match' (program line 255), at (input Line 92 Pos 25)

if (obj.http.etag ~ req.http.if-none-match) {

---

Running VCC-compiler failed, exit 1 VCL compilation failed

[hamnis]

The right hand side of the expression is not evaluated.

[phk]

The exact scenario you propose is unlikely to be possible, because compiling regular expressions is horribly expensive (malloc overhead amongst other things).

The other half of it, is that it is so suicidal to allow a client to send you regexps that it defies description.

(In VCL we precompile the regular expressions at load-time to minimize this overhead.)

In r4186 I have changed the VCL compiler so that the "==" and "!=" operators take general strings as arguments, so replacing your "~" with "==" the above should now be possible.