using LWP::UserAgent and DBI together

sourav has asked for the wisdom of the Perl Monks concerning the following question:

Hello Gurus!
I am not new to Perl, however, pretty new to this module LWP::UserAgent, which I recently started using to send a http server and based on the request execute a proc in the database. Well, it didn't work. After a lot of searching through the code, I tried doing this:

use DBI;
use LWP::UserAgent;

my $ua = LWP::UserAgent->new;
my $r = $ua->post('http://localhost/');

my $dbh = DBI->connect("dbi:Sybase:server=$server", '$uid', '$password
+') || die "Bad db server, no donuts!";
my $sql = "declare \@rc int exec \@rc = myProcName " . 
          "select \@rc";
$row = $dbh->selectall_arrayref($sql);
print $row->[0][0], "\n";
[download]

It fell into an infinite wait until I manually stopped execution by Ctrl-C. However, commenting out the line of the post request, the script runs successfully... whats going wrong here? Can anyone please suggest what's the problem here and if there are any workarounds...

I am using ActivePerl 5.6 on Windows.

Comment on using LWP::UserAgent and DBI together Download Code

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Re: using LWP::UserAgent and DBI together by pajout (Curate) on Nov 09, 2009 at 15:15 UTC
I guess your http server is not responding the request made by $ua and $ua just waits for that response. Sourav, you should primarily decide, what do you want - if your goal is direct connection with some sql database engine (rdbms), DBI and proper DBD:: driver is a good choice. You can connect local rdbms (the software running on the same computer as your perl code), or you can connect remote rdbms, typically via pure tcp/ip protocol. But if you want to establish communication with http server (local or remote, which is evident from url), you can use LWP::UserAgent and related modules. Update: I apologize if I did not understand you correctly, perhaps you want to do both, http request and some sql command...	[reply]
Re^2: using LWP::UserAgent and DBI together by sourav (Initiate) on Nov 09, 2009 at 15:42 UTC
That's right, I'd like to use both a http request and a database connection. My main requirement is - send a post request to a http server and see what the response is, if it's a success, then run a stored proc at the backend to update a table with the response from the http server. The code I posted is a simplfied form of the actual code, which curently waits infinitely during the $dbh->selectall_arrayref() execution (and not the $ua = LWP::UserAgent->new() call). I guess there are some problems when you are using both these two modules in a single script, however, I could not find any specific document describing the source of the problem or anything to solve it (that is, to have a http request and a dbi call in the same script). Any help?	[reply]
Re^3: using LWP::UserAgent and DBI together by sourav (Initiate) on Nov 09, 2009 at 15:50 UTC
One more thing I might add... I tried replicating the same problem with ActivePerl 5.8, here it seems to be working fine without a glitch... but I can't use this version at work (that's only 5.6 there)....	[reply]