On Tue, Apr 18, 2023 at 12:56 AM Willy Tarreau <[email protected]> wrote: > > Hi Jim, > > [side note: please guys, avoid top-posting, it makes it very difficult > to quote context in responses]
Repenting as fast as I can ... * https://en.wikipedia.org/wiki/Posting_style#Interleaved_style ( does a list etiquette guide exist ? ) > On Mon, Apr 17, 2023 at 09:17:03PM -0600, Jim Freeman wrote: > > Aleksandar - thanks for the feedback ! (haproxy -vv : attached) > > > > I'd spent a good long while scouring the config docs (and Google) seeking > > enlightenment, but ... > > No joy using either of '! -m found -m int 0' or '! -m found'. > > > > Here's hoping someone/anyone else has experience making an empty field() > > work ... > (...) ... > Just a warning below though: > > > > > acl COOK_META_MISSING req.cook(cook2hdr),field(3,\#) ! -m found -m > > > > str '' > > I have no idea how that parses to be honest, because a single match > method may be used and normally whatever follows the first pattern are > other patterns. Since the "found" match doesn't take any pattern, it's > likely that "-m str ''" is still parsed and possibly replaces -m found, > but I wouldn't count on that. > > So if you want to consider as missing a cookie that is either not present > or that is empty, I would probably do it this way: > > acl COOK_META_MISSING req.cook(cook2hdr),field(3,\#) ! -m found > acl COOK_META_MISSING req.cook(cook2hdr),field(3,\#) -m len 0 > > This ACL will be true if the cookie's value was not found, or if it > was found but with an empty length. > > hoping this helps, > Willy Expressing the acl's OR across multiple lines did indeed help - many thanks ! My sense from googling was that the multiple '-m ...' clauses should work (and would be more succinct) is hereby proven wrong, and your explication of the vagaries of second '-m ...' relative to the preceding one is a very helpful insight and caution flag. The crux of that I guess is understanding that "whatever follows the first pattern are other patterns" - that didn't register in my study of the config docs. I'd wish to not have to double up the number of lines per field, but understand that the in-memory expression is very efficient. As always - HAProxy rocks hardcore and world-class !! Thanks again, ...jfree
