Re: Apache2::Filter Intermittently Missing Injected String

Am Mi, 30.03.2011, 12:17 schrieb Chris Datfung:
> I have a script that uses Apache2::Filter to filter the server response
> output and inject a string into the HTML body. The script normally works
> fine expect intermittently the output is missing the injected string. This
> happens around 10% of the time. I verified that there is enough memory and
> CPU available and tried playing with the buffer size, but to no avail.
>
> The server is running:
>
> Apache 2.2.17-2
> Modperl 2.0.4-7
>
> Any explanation for why the script fails 10% of the time?
>
> Thanks
> Chris
>

I had a similar problem with a http proxy that injected a string into the
HTML body. If the response is passed to the filter in multiple parts there
is a certain probability that the response is split on the string position
you are looking for (for example part 2 ends with "</bo" and part 3 starts
with "dy>"). I had to buffer the last bytes of each response part and take
them into account when looking for the search-string in the next part. I
dont know though if this is possible in Apache2::Filter or if this is your
problem at all.

Hendrik