Hi,
On Fri, Jun 29, Baptiste wrote:
> converters are just simple C functions, (or could be Lua code as well), and
> are quite trivial to write.
> Instead of creating a converter that reverse the order of chars in a
> string, I would rather patch current "word" converter to support negative
> integers.
> IE: -2 would means you extract the second word, starting at the end of the
> string.
No need to patch "word" for negative indexes. The functionality is
already there:
commit 9631a28275b7c04f441f7d1c3706a765586844e7
Author: Marcin Deranek <marcin.dera...@booking.com>
Date: Mon Apr 16 14:30:46 2018 +0200
MEDIUM: sample: Extend functionality for field/word converters
Extend functionality of field/word converters, so it's possible
to extract field(s)/word(s) counting from the beginning/end and/or
extract multiple fields/words (including separators) eg.
str(f1_f2_f3__f5),field(2,_,2) # f2_f3
str(f1_f2_f3__f5),field(2,_,0) # f2_f3__f5
str(f1_f2_f3__f5),field(-2,_,3) # f2_f3_
str(f1_f2_f3__f5),field(-3,_,0) # f1_f2_f3
str(w1_w2_w3___w4),word(3,_,2) # w3___w4
str(w1_w2_w3___w4),word(2,_,0) # w2_w3___w4
str(w1_w2_w3___w4),word(-2,_,3) # w1_w2_w3
str(w1_w2_w3___w4),word(-3,_,0) # w1_w2;
-Jarno
> On Mon, Jun 25, 2018 at 12:29 PM, Daniel Schneller <
> daniel.schnel...@centerdevice.com> wrote:
>
> > Hi!
> >
> > Just double checking to make sure I am not simply blind: Is there a way to
> > reverse a string using a sample converter?
> >
> > Background: I need to extract just the second level domain from the host
> > header. So for sub.sample.example.com I need to fetch "example".
> >
> > Using the "word" converter and a "." as the separator I can get at the
> > individual components, but because the number of nested subdomains varies,
> > I cannot use that directly.
> >
> > My idea was to just reverse the full domain (removing a potential port
> > number first), get word(2) and reverse again. Is that possible? Or is there
> > an even better function I can use? I am thinking this must be a common use
> > case, but googling "haproxy" and "reverse" will naturally turn up lots of
> > results talking about "reverse proxying".
> >
> > If possible, I would like to avoid using maps to keep this thing as
> > generic as possible.
> >
> > Thanks a lot!
> >
> > Daniel
--
Jarno Huuskonen
