HTTP::Request failed on HTTP/1.1 and Connection: Keep-Alive

[Simon Tneoh]

Hi Abigail,
I know that the error comes from the Java program, the nullpointer error.
But what it confused me is: if I'm using an Internet Explorer version 5 to
access the page, it's working fine. If I use HTTP::Request, it'll fail. I tried
to simulate the headers in the IE's request in HTTP::Request, but I failed to
make it work. I just wonder if it's because HTTP::Request doesn't support
HTTP/1.1 and Keep-Alive properly?
Thanks.

Regards,
Simon.

Abigail <abigail@abigail.nl> wrote in message news:<slrnbhfts1.1e7.abigail@alexandra.abigail.nl> ...

> Simon Tneoh (simon.tneoh@mybiz.net) wrote on MMMDCVIII September MCMXCIII
> in <URL:news:a07bdd22.0307180516.3c1d95e2@posting.goo gle.com>:
> -: Hello all,
> -: Thanks in advance for any helps provided.
> -: I try to download a page through GET method with protocol HTTP/1.1
> -: by
> -: using HTTP::Request module and it fails.
>
> And the error you show us is a Java trace. The Java program makes
> one of the most common errors in Java programs: nullpointer
> exception.
>
> But Java has *nothing* to do with the charter of this group.
>
>
>
> Abigail

[MegaZone]

[email]simon.tneoh@mybiz.net[/email] (Simon Tneoh) shaped the electrons to say:

>to simulate the headers in the IE's request in HTTP::Request, but I failed to
>make it work. I just wonder if it's because HTTP::Request doesn't support
>HTTP/1.1 and Keep-Alive properly?

I'd probably throw a sniffer at it (like Etherial) - grab the headers
from the successful IE connect, and the unsuccessful Perl connect, and
see what differs - then see what I might be able to do to make the
Perl options resemble the IE configuration.

Presuming the Java were a black box. (Been there, done that -
sometimes you *can't* 'fix' the other bit, you just to make your bit
work with it as is.)

But if you do have the ability to tweak the Java, add some better
error handling to at least trap what is going wrong.

-MZ, CISSP #3762, RHCE #806199299900541
--
<URL:mailto:megazone@megazone.org> Gweep, Discordian, Author, Engineer, me..
"A little nonsense now and then, is relished by the wisest men" 508-755-4098
<URL:http://www.megazone.org/> <URL:http://www.eyrie-productions.com/> Eris

[trwww]

[email]simon.tneoh@mybiz.net[/email] (Simon Tneoh) wrote in message news:<a07bdd22.0308041753.2c82307d@posting.google. com>...

> Hi Abigail,
> I know that the error comes from the Java program, the nullpointer error.
> But what it confused me is: if I'm using an Internet Explorer version 5 to
> access the page, it's working fine. If I use HTTP::Request, it'll fail. I tried
> to simulate the headers in the IE's request in HTTP::Request, but I failed to
> make it work. I just wonder if it's because HTTP::Request doesn't support
> HTTP/1.1 and Keep-Alive properly?
> Thanks.
>

I highly doubt it. I know it is easy to blame the perl end of the
connection when one sees something like the above, but it is usually
not the case.

For instance, developing an asp.net app, my code used the
HttpContext.Current.Request.UserAgent object from the .NET class
library. When I made requests via IE or NS, everything was gravy. But
when I used LWP::Simple to develop a test suite, the app would crash
saying I was using a null value as an object.

After stepping through the code with the debugger, I saw
HttpContext.Current.Request.UserAgent was null when using LWP::Simple.

HttpContext.Current.Request.UserAgent is a convience object and is by
no means obligated to be instantiated ( by specification or otherwise
).

So while it was easy to immediately think the problem was in the
client side perl logic, some digging proved the problem was indeed on
the server side.

Todd W.