perl -le'print $_,"\t",sin($_/10)+sin(($_/30))**2*0.2+sin($_/500)*0.4+
+4+(rand()+rand()+rand()+rand())/20 for 0..6000' > testdata.txt
[download]

Wisdom I seek ..

I am receiving JSON serialized objects for some perl classes. I can easily de-serialize the JSON structure back into perl data structure - hash/array using standard JSON modules and possibly into a blessed reference.

However, when the serialized class represents objects and sub-objects, I have no way to automatically create blessed reference for sub-objects.

Storable module can easily de-serialize and create blessed references for sub-objects automatically. Is there a way to do the same for JSON?

I went into the module itself and added debug statements to dump the url's posted to, to STDERR.

I'm told by those on the #civicrm irc channel that the API uses the field names provided by the database tables as keys in its methods. I've checked the drpl_users table and in fact the keys in my login method's arguments do in fact match those field names from the table.

When I harvest the url from output, and run that in a browser, it gets me to an access denied page, with a login form. Using these credentials on that login form gets me to the civiCRM menu page, suggesting to me that the url is at least reasonably well formed.

There are several other tests coded and failing at this point, but they are all expected to (and in fact do) fail unless the ->login() method succeeds. Any and all ideas for how to move past this issue would be appreciated.

Thanks,
-- Hugh

#!/usr/bin/perl
use strict;
use warnings;

use CiviCRM::Client;
use Data::Dumper;

my $civicrm = CiviCRM::Client::REST->new(
'http://example.org', '37736c686aeGrt54skk705bfa9a9Hgsfll81');

print STDERR Dumper($civicrm);

if($civicrm->login({ 'name' => 'hesco', 'pass' => 'secret' })){
  print STDERR "succeeded in login attempt \n";
} else {
  print STDERR "failed to login \n";
}

[download]

$VAR1 = bless( {
                 '_civicrmUrl' => 'http://example.org',
                 '_ua' => bless( {
                                   'max_redirect' => 7,
                                   'protocols_forbidden' => undef,
                                   'show_progress' => undef,
                                   'handlers' => {
                                                   'response_header' =
+> bless( [
                                                                      
+           {
                                                                      
+             'owner' => 'LWP::UserAgent::parse_head',
                                                                      
+             'callback' => sub { "DUMMY" },
                                                                      
+             'm_media_type' => 'html',
                                                                      
+             'line' => '/usr/local/share/perl/5.10.0/LWP/UserAgent.pm
+:608'
                                                                      
+           }
                                                                      
+         ], 'HTTP::Config' )
                                                 },
                                   'no_proxy' => [],
                                   'protocols_allowed' => undef,
                                   'use_eval' => 1,
                                   'requests_redirectable' => [
                                                                'GET',
                                                                'HEAD'
                                                              ],
                                   'timeout' => 180,
                                   'def_headers' => bless( {
                                                             'user-age
+nt' => 'libwww-perl/5.830'
                                                           }, 'HTTP::H
+eaders' ),
                                   'proxy' => {},
                                   'max_size' => undef
                                 }, 'LWP::UserAgent' ),
                 '_sessionKeyName' => 'key',
                 '_siteKey' => '37736c686aeGrt54skk705bfa9a9Hgsfll81'
               }, 'CiviCRM::Client::REST' );
failed to login
[download]

Hi

I am making some small server using sockets in non-blocking mode. I want to check if the client (telnet) is still connected, but I don't know how.

Reading routine looks like that (from web):

$rv = sysread($sock2, $buffer, $BUFSIZ);
if (!defined($rv) && $! == EAGAIN) { } # HERE
else { print $sock1 $buffer; }
 
[download]

I suppose that HERE I should check for some disconnect error, but I am not sure...

Oh Monks, help me with your wisdom!

i was messing around with implementing some security into my program and i noticed some strange thing in one of my foreach loops

foreach (@array){

do something
$self->_call($_);
do something else
}
[download]

if this is the case then please help me with some quick fix.

thnx

PS

it is interesting that i always stumble over some basic stuff, did anyone noticed the same problem (stumbling over basics while at the same time writing solutions to a really hardcore stuff)?

UPDATE:

ok what happens is this:

sub _do {

my ($self,%arg) = @_;

unless(%arg){


# some stuff (~200 lines)


foreach my $choice (@array_choices){                                 #
+ log update
        my @choice_array = split(",",$print_hash{$choice});
        my $pick;
        ($choice_array[0] eq 'correct') ? ($pick = "$choice_array[1]-$
+choice_array[2]") : ($pick = $choice_array[1]);  # pick for correctio
+n
        $self->_do($choice_array[0] => $pick);                        
+   # repete undo precedure with defined values
        ($choice_array[0] eq 'correct') ? (delete $class_log{do}[$hash
+_order{$choice_array[0]}]) : (delete $class_log{do}[$hash_order{$prin
+t_hash{$choice}}]);         # delete do choice
        push(@return_log,"_do($choice_array[0] => $choice_array[1]);")
+ unless (ref $pick eq 'ARRAY');                 # data for physh
        push(@return_log,"_do($choice_array[0] => \[$choice_array[1],$
+choice_array[2]\]);") if (ref $pick eq 'ARRAY');# data for physh
    }

}
else{

# brute _do

}
}
[download]

I need your help yet again. The below code is mostly re-used. The sub-routine (not listed) is used by a dozen scripts and works great. The query itself works fine if I try it out on a single database.

However when I run this the results are not even close to accurate. Can anyone see any glaring errors? I thought maybe the space that was in the hash keys was the issue so I fixed that but still dosen't work. Been tinkering with this for well over 2 hours..and it's starting to erk me. This should be simple..but it's not.

What it's doing is getting a number of times a user takes something ..the key is a date/hour concat so in essence I want the number of times a user took something for each date/hour (for those date/hours that have takes). There should be a max of 24 lines per host (so 24*3 which is 3 days, 24 hours in each day). Im getting 8 lines with 200ish results..should be A LOT more..both in terms of lines and the #'s returned (I'd expect them to be between 100's and 10,000's).

#!/usr/bin/perl

use strict;
use warnings;
use DBD::mysql;

######################
#### CONFIG VARS #####
######################

my $output_file = 'Takes_by_hour.txt';

######################
#### PRIVATE VARS ####
######################


my $start_date = '2009-10-04';
my $end_date = '2009-10-06';

######################
#### MAIN BODY #######
######################

open OUTPUT, ">$output_file";
select(OUTPUT); $| = 1;
select(STDOUT); $| = 1;
        
while (my ($host, $default_db) = each(%hosts)) {
    my %take_counts = ();
    
    #get database urls for host
    my @databases = get_databases($host, $default_db, $db_user, $db_pa
+ss);
    @databases = sort(@databases);

    #process data on each database
    foreach my $database (@databases) {
        print join ("/", $host, $database) . "\n";
        
        #Get List of Instructor with active/current courses
        my $dbh = DBI->connect("DBI:mysql:database=$database:host=$hos
+t",$db_user,$db_pass,{RaiseError=>1})|| die "$DBI::errstr\n";
        my $sql = "SELECT DATE_FORMAT(ar.StartedAt,'%b%d-%k') AS DateT
+aken, COUNT(ar.UserID) 
               FROM Assignments AS a JOIN AssignmentResults AS ar ON a
+.ID=ar.AssignmentID 
               WHERE DATE(ar.StartedAt) BETWEEN '$start_date' AND '$en
+d_date' GROUP BY DateTaken";
        my $sth = $dbh->prepare ( $sql );
        $sth->execute();

        while (my @row = $sth->fetchrow_array()) {
            if (exists $take_counts{$row[0]}) { 
                $take_counts{$row[0]} += $row[1];
            }
            else { 
                $take_counts{$row[0]} = $row[1];
            }
        }
        $sth->finish();
        $dbh->disconnect();
    }
    foreach (my ($key, $value) = each (%take_counts)) {
        print OUTPUT "$host\t$key\t$value\n";
    }

}

close OUTPUT;

[download]

Thanks again for any help that you can provide.

Kevin M

#!/usr/bin/perl

use strict;
use warnings;
use LWP;

my $path = "Infrastruktur/Svitsjoversikt";
my $loginurl = "http://intranett.oikt.local/user/login";
my $finaluri = "/Infrastruktur/Svitsjoversikt";
my $user = "foo";
my $pass = "bar";
my $param = "Login=$user&Password=$pass&LoginButton=1&RedirectURI=$fin
+aluri";

# Create a user agent
my $ua = LWP::UserAgent->new;
$ua->agent("monitorezex/1.0 ");
#push @{ $ua->requests_redirectable }, 'POST';   # Make POST requests 
+redirectable
$ua->cookie_jar({ file => "cookies.txt" });

# Create a request
my $req = HTTP::Request->new(
  POST => $loginurl
);
$req->content_type('application/x-www-form-urlencoded');
$req->content( $param );

# Pass request to the user agent and get a response back
my $res = $ua->request($req);

# Check the outcome of the response
if ($res->is_success) {
  print "SUCCESS!\n";
  print $res->as_string;
} else {
  print "FAILURE: " . $res->status_line . "\n";
  print $res->as_string;
}
exit;
[download]

HTTP/1.1 302 Found
Cache-Control: no-cache, must-revalidate
Connection: close
Date: Fri, 09 Oct 2009 06:45:56 GMT
Pragma: no-cache
Location: http://intranett.oikt.local/Infrastruktur/Svitsjoversikt
Location: http://intranett.oikt.local/Infrastruktur/Svitsjoversikt
Server: Apache/1.3.39 (Win32) PHP/5.2.6
Content-Language: no-bokmaal
Content-Type: text/html; charset=utf-8
Expires: Mon, 26 Jul 1997 05:00:00 GMT
Last-Modified: Fri, 09 Oct 2009 06:45:56 GMT
Client-Date: Fri, 09 Oct 2009 06:45:56 GMT
Client-Peer: 10.10.8.120:80
Client-Response-Num: 1
Client-Transfer-Encoding: chunked
Refresh: 0;URL=http://intranett.oikt.local/Infrastruktur/Svitsjoversik
+t
Served-By: intranett.oikt.local
Set-Cookie: eZSESSIDoikt_intranett=v8igadrdc86koc225jk55or5e2; path=/
X-Powered-By: eZ Publish

<HTML><HEAD><META HTTP-EQUIV="Refresh" Content="0;URL=http://intranett
+.oikt.local/Infrastruktur/Svitsjoversikt"><META HTTP-EQUIV="Location"
+ Content="http://intranett.oikt.local/Infrastruktur/Svitsjoversikt"><
+/HEAD><BODY></BODY></HTML>
[download]

10.15.0.2 - - [09/Oct/2009:08:38:31 +0200] "POST /user/login HTTP/1.1"
+ 302 246
10.15.0.2 - - [09/Oct/2009:08:38:32 +0200] "GET /Infrastruktur/Svitsjo
+versikt,%20http://intranett.oikt.local/Infrastruktur/Svitsjoversikt H
+TTP/1.1" 404 23015
[download]

                        while (my @row = $sth->fetchrow_array()){
                            my $parser = XML::LibXML->new();
                            my $doc = $parser->parse($row[0]);
                            my $root = $doc->documentElement();

                            my %linked_counts_by_abbr;
                            for my $usage_node ($root->findnodes('/Boo
+kReferences/BookUsage')) {
                                my $abbr         = $usage_node->getAtt
+ribute('BookAbbr');
                                my $linked_count = $usage_node->getAtt
+ribute('LinkedCount');
                                $linked_counts_by_abbr{$abbr} += $link
+ed_count;
                            }
                            foreach (my ($key, $value) = each %linked_
+counts_by_abbr){
                                print OUTPUT "$key => $value\n";
                            }
                        }
[download]

Can't locate auto/XML/LibXML/parse.al in @INC (@INC contains: /etc/perl /usr/local/lib/perl/5.8.8 /usr/local/share/perl/5.8.8 /usr/lib/perl5 /usr/share/perl5 /usr/lib/perl/5.8 /usr/share/perl/5.8 /usr/local/lib/site_perl /usr/local/lib/perl/5.8.4 /usr/local/share/perl/5.8.4 .) at registrations_by_discipline_with_contacts.pl line 139

Any suggestions? libxml-parser-perl package v2.34 is installed along with the necessary dependencies and I'm on Debian GNU/Linux 4.0 but don't have SUDO privilages and I log in to the sytem remotely via a VPN connection.

I am moving data from an xml-file into a mysql db and need to make a substitution on the fly to clean up a string so it matches the required "datetime" format (replace a letter with a space and truncate). I naively added the substitution expression to the bind value in the script below and got the following error message:

Can't modify non-lvalue subroutine call at blabla.pl line X

use strict;
use DBI;
use XML::XPath
use XML::XPath::XMLParser;

my $dbh = DBI->connect ("DBI:mysql:database",
                           "root", "password",
                           { RaiseError => 1, PrintError => 0});
my $xp = XML::XPath->new (filename => "input_file.xml");
my $nodelist = $xp->find ('//row');
foreach my $row ($nodelist->get_nodelist ())
   {
   $dbh->do  ("INSERT INTO users1 ( create_string, username)  VALUES (
+?, ?)",
                undef, # no need for \%attr
                $row->find ("CreateDate")->string_value () =~ s/(\d\d\
+d\d-\d\d-\d\d)T(\d\d:\d\d:\d\d).*00/$1 $2/g,
                $row->find ("UserName")->string_value ());
   }
$dbh->disconnect ()
[download]

Sample data
<USERS1>
  <row>
    <CreateDate>2008-03-17T13:31:14.345-07:00</CreateDate>
    <UserName>foo</UserName>
    <Email>michael@example.com</Email>
    <UserId>a58d0b09-4f97-42ef-901e-cee41103bc12</UserId>
  </row>
  <row>
    <CreateDate>2008-04-11T14:59:57.123-07:00</CreateDate>
    <UserName>bar</UserName>
    <Email>spot@example.com</Email>
    <UserId>4b618e05-1eca-494b-baa5-ab85bd46f0f3</UserId>
  </row>
</USERS1>
[download]

create_table_users1.sql
CREATE TABLE users1
(
    create_string datetime  ,
    username    varchar(32) );
[download]

Some monks have already noted that the proof that Perl parsing is not, in general, decidable applies equally to all parsing by the Perl interpreter or by Perl scripts. This point had already been made in my series on "Perl and Undecidability" in The Perl Review. [ This is now available online ]. Despite this, some confusion remains on whether, in general, Perl might be "dynamically" parseable.

The Perl Parsing Undecidability proof shows that a Turing machine cannot, in general, parse Perl. Whether running a script, or parsing, the Perl interpreter, and any program implementing the Perl language is, as far as Perl parsing goes, a Turing machine.

This means that how you define "static" and "dynamic" Perl parsing does not matter. All Perl processing is at best equivalent to a Turing machine. And therefore none of it suffices to parse Perl in general.

The confusion does have a reasonable basis in some common sense observations. In practice, Perl almost always does parse itself just fine, despite any difficulties people may have writing tools to analyze Perl scripts. And there is a very convincing (though fallacious) counter-argument.

Fallacious Counter-Argument: First, let's reduce the problem of Perl parsing to the issue of determining whether a function's prototype is nullary or not. If it's proved that determining nullarity is, in general, decidable, it reduces my original proof to rubble. It probably also generalizes to a full counter-proof.

Consider the following code snippet:

sub runtime_nullary {
    my $function = shift;
    return 0
        if not defined( my $prototype = prototype $function );
    return $prototype eq q{};
} ## end sub runtime_nullary

print 'nullary dunno: ';
say runtime_nullary('dunno') ? 'yes' : 'no';

print 'result is ';
say dunno +4;
[download]

1. Something like the above can placed to execute first (or early) in the run phase.
2. We can place this code so that we always reach it and execute it.
3. Once runtime_nullary runs, we know whether the function named in its argument is nullary or not.
4. We can run runtime_nullary on any function we like, and on as many functions as necessary.

So therefore, Fallacious Conclusion: We can in general determine whether any Perl function has a nullary prototype or not.

First, let me concede that the Fallacious Conclusion does follow from Observations 1-4. Let me also concede that Observations 1, 3 and 4 are correct. And let me also concede that if Fallacious Conclusion is correct, my Perl Parsing Undecidability Proof (and probably any other) is kaput.

But what about Observation 2? It looks solid, but it hides a major fallacy. We reach the run phase only if we get out of the compile phase. True, this is something we usually take for granted, but it we assume the compile phase eventually ends (or that we can tell whether it will or not), we assume there is no Halting Problem in the compile phase. And if we assume that there is no Halting Problem in Perl's compile phase, we assume that the compile phase does not have Turing machine power.

Perl's compile phase does have Turing machine power, and therefore is subject to the Halting Problem. This is not just a fact, but it is exactly that property of Perl which causes Perl parsing to not, in general, be decidable. The ghost of the Halting Problem must always haunt those who seek the power of the One Universal Machine to Bind Them All.

Update: I simplified the code snippet a bit to focus on my point in this post. The original is on page 25 of the Fall 2008 issue of The Perl Review.

As life would have it, there was not a lot of opportunity to solve world hunger, or create ever lasting peace via a computer language, so she had to settle for something a little less dramatic. With one young son in elementary school, the school seemed to be overflowing with young minds which could be brought to the pleasures of Perl.

Quest one

A plan began to bubble forth, and congealed into an idea... teaching the older children how to program, using Perl. After school. After classes. For free! I repeat, for free! She approached the court with a plan, to be told that much consideration must be given before allowing an unknown subject within the castle walls. Access to the magic of the computers could be potentially dangerous, although how so, the court did not seem to know, only that they had been told by the great IT wizard that said that this was so.

After many months (I am not kidding here, it took from the beginning of Sept to mid-November), the court decreed that, in spite of no blessings by the IT wizards, that they would take the risk.

At this point, the humble programmer's trusted man-servant and she taught (or at least attempted to teach) the wonders of Perl to the young vassals, and helped those interested minds find the beginning paths to the wonders of computer programming.

Through this journey of 14 weeks, the Queen never once took notice of this humble programmer, nor of her quest.

However, the humble programmer's reward was the joy on the children's faces when they could make the computer make farting noises on command! Ah, the joy of youth.

Quest two

How, the programmer said to herself, could a good cleaning truly be a noble quest. Once cleaned, dust would simply gather again and again. Perhaps it was time to bring forth the heros of web development, Earl Template, Duchess CSS, and Duke Content Management of System.

But there are hazards on this quest. The Great School Board Server was protected by the mighty IT wizards, who allow no Open Source Software to dirty their pristine MS environment. None shall enter (or have access to) the Great School Board Server.

So the quest begins, and with the help of the magic of Perl, the magic of wiki, templates, and css, a peasant's Content Management System is devised that will allow the court to manage the web-content via very simple wiki, and beautiful pages of html shall be produced. The only thing missing is the magic incantation to put these html pages on the Great School Board Server.

The Queen and her trusty servant, who dabbles in web-magic, were petitioned for a hearing. The trusty servant, able to produce web pages with minimal flair, was not interested on expanding her knowledge of web-magic, nor was she interested in modifying the results of her incantations. All shall remain as is.

As with all great tales, the fates intervened. The Queen's trusted web-dabbler moved on to fairer shores, leaving this castle with no one to spin-webs. During the summer months of inactivity, our humble programmer worked feverishly using her magic incantations, and the mighty web heroes, to transform the dusty dried web into a dew-sparkled work of beauty (ok, a little exaggeration, but this is just a story...). The new dew-sparkled web site had been infused with the magic of java-script drop-down menus, starting only with a single drop of YAML text, a drop of templates, therein multiplying to all of the web pages, so each would share a common core. In her quest for simplicity of maintenance, our humble programmer had decreed that nothing shall be written twice. Pictoral tales (appropriately sized for the great internet) of great sport or celebration can be conjured with a simple flick of the wrist. The goal, again, was to provide magic where the incantations could be performed by those not in the least bit skilled in the art of spinning webs.

During this time of feverish activity, she joined forces with another knight, highly skilled in the art of Volunteer. The two schemed unabashedly to defeat the curses that cause outdated websites. When the court came back from holidays, requests for hearings were once again put forth. The Queen took no delight in outsiders' help, and would have no discourse with either of the two subjects.

True to her skill as a great volunteer, our Knight petitioned those even more powerful than the Queen, beseeching them to ensure a reputation worthy of new enrollment by painting the web in beautiful colours. "It has already been done", she cried, "the only thing missing is the transfer to the Great School Board Server". And lo and behold, the greater powers decreed that this shall be done.

Although a great achievement had been attained, the quest has not yet ended, for there still lurks the curses of dusty and dried-up websites. The Great School Board, where great decisions are made, hired a young eager apprentice web-spinner, not only to aid the Queen in this story, but all the Kings and Queens under the umbrella of the Great School Board. However, this poor apprentice was shackled with the curse of 'no open-source', and could not have access to our humble programmer's magic.

What, pray tell, shall be done? The Queen has at her side, a fair young maiden, wishing to be indoctrinated in the arts of web spinning, or so the Queen claims. Overtures were made to this young maiden, with promises of spells and potions to recreate and enhance the freshly dusted web site. Deafened by what we know not, the young maiden made no reply. Again and again our humble programmer and Knight Volunteer made overtures, and again and again they fell on deaf ears. Pleas were made to the Queen. "Help", they cried, "we do not wish to see the freshly spun web dry up into dust, it must be constantly freshened. Please do not let it lie fallow."

The Queen responded by ignoring the two servants, and appealed for web-magic from the young apprentice at the Great School Board. The apprentice in turn could not offer what was required, as she was busy with spells for other kingdoms. The not-so-young humble programmer almost gave up the quest, but was heartened by Knight Volunteer's stories of noble quests, completed in spite of many obstacles, where the rewards were many. The Great Knight Volunteer also recounted tales of appreciation by many of those in the court.

Faced with many appeals and cries of outrage by our valiant Knight Volunteer, the Queen condescended to request website dustings from our humble programmer. However, the ever mystical username/password required to upload to the Great School Board Server was still unknown to all within the castle walls. The young maiden, whom it was said wished to be a web spinning apprentice, was still mystified by all that said "html".

Although freshly dusted html sits on our humble programmer's laptop, the website itself begins to gather dust. Our humble programmer begins to feel that the quest was not so noble after all, because no matter how pretty, an out-of-date web-site is simply no better than the out-of-date information contained therein. The humble programmer and the Knight Volunteer were again beseeching all and sundry for someone, anyone to ask for and obtain the mystical username/password so that the castle web-aspiring apprentice could at least upload to the Great School Board Server. All requests were ignored.

"What to do! What to do!" cried our humble programmer and Knight Volunteer in unison. Our Knight Volunteer grabbed her lance, her armour and her unshakable determination, and went forth to confront the Queen. Unknown to our fair Knight, the Queen employed the evil of unknown forces, who sent a Dragon to swallow our fair Knight whole. The Dragon was successful at knocking the fair Knight off of her feet, and declared that the Knight Volunteer must never again involve herself in anything to do with the now dusty website.

The humble programmer, unaware of the of Dragon or his intentions, arranged an audience with the Queen. "Much goes on in my mighty kingdom that you are not aware of", says the Queen to the programmer. "All spinning of webs must come from me or one of my own. It is not allowed for outsiders to be privy to our magics."

"But", cried the humble programmer, "I have repeatedly beseeched you and your aspiring web apprentice for an audience so that I may impart my thoughts and experiences, as well as to deliver the magics and potions that can create web sites with a few simple incantations. I have been repeatedly ignored. My only humble request is that this meeting not take me away from those tasks that, indirectly, put food on my table."

The audience has been tentatively committed for two weeks from this telling.

Our humble programmer is no longer eager to save the world from anything. Our humble programmer wonders if the Queen should have access to her magics before they are dispersed into the winds via CPAN. However, hubris (one of the three virtues of a progammer) makes our programmer very proud of her work, and the resulting website. There would be great disappointment if the website did not take root and flourish. "What to do?"

If there is a moral to this incomplete quest, it is simply

"Do not volunteer your efforts, no matter how noble, no matter how supported by those around you, unless the Queen Bee wants your help."

What to do?

Padre is using Actions for menu options, shortcuts, etc. The Action for showing the Perl help search (F2) is handled by the following piece of source:

for ( @{ $self->{event} } ) {
     next if ref($_) ne 'CODE';
     &{$_}(@args);
}
[download]

print "---START---\n";
for ( @{ $self->{event} } ) {
     print STDERR $self->{name}." => $_\n";
     next if ref($_) ne 'CODE';
     &{$_}(@args);
}
[download]

---START---
help.search => CODE(0x9bcb9b0)
help.search => CODE(0xa2f8618)
---START---
help.search => -f
help.search => CODE(0xa2f8618)
[download]

print "---START---\n";
for my $item ( @{ $self->{event} } ) {
     print STDERR $self->{name}." => $item\n";
     next if ref($item) ne 'CODE';
     &{$item}(@args);
}
[download]

---START---
help.search => CODE(0x9bcb9b0)
help.search => CODE(0xa2f8618)
---START---
help.search => CODE(0x9bcb9b0)
help.search => CODE(0xa2f8618)
[download]

$_ was used by the loop, but it was no copy of the first array item, it was referencing it. Because something in the called CODE(0x9bcb9b0) was using $_, the new value was stored into the referenced place - the first array item overriding it's own CODE-reference.
By using a private (my) variable for the loop, $_ isn't used any longer and the problem was gone: http://padre.perlide.org/trac/changeset/8727/trunk/Padre/lib/Padre/Action.pm

This is a common problem which triggers Perl newbies and experts and which is usually hard to find, because the errors occurs at a place somewhere later when using the modified data, but if you respect this rule, you should be safe:
Use a private my-variable for looping whenever you call a sub or method within your loop!

Then I started dreaming. Disks are slow. Only right way to read them is sequentially, so it rules out disk as storage if you want to have fast access. So, what is fastest way to run perl snippets? In memory.

But, I would run out of memory eventually. So I would have to support sharding across bunch of machines... That would also enable me to scale linearly just by adding a new machine or two...

I just had a bunch of web kiosks running Debian live around, so I decided to try does this idea sound sane in a week. And sure enough, I had working version after a week.

Then I decided to rip it apart and rewrite into simpler one which is modeled around management of individual nodes and much simpler network protocol. And I discovered that parsing file on master node isn't bad because it cuts down on required dependencies on deployment. And with a little bit of caching it even provides speedup on startup.

In this stage, it's quite usable toy. I would really appreciate feedback about it. Is it interesting for other people to try it? Or did I just learned a few lessons about scalability that everybody else already knows?

And lastly how would you release such a toy? CPAN doesn't really seems like a right place, so is Ohloh enough? It's not in git, so github isn't really an option.

Will take a list of hosts from either STDIN or a file. It will resolve the hosts and then try to access them using SSH to extract manufacturer, serial number and product name using dmidecode. It will then access the manufacturers support page to determine the warranty of the host. Currently it works with IBM, HP and DELL.

Assumes you are using SSH Public Keys, if your key has a password use ssh-agent to automate the password typing.

Using it on HP has some shortcomings because of their support page. It requires you to specify country and product number, neither is possbile to extract from a host in any automated faschion. To work around this issue there is a convertion table for HP product name to product number and country will need to be specified either per subnet or one default location.

This Padre plugin allows users to type shell commands/scripts into the active document and run them. The output from the command is then inserted into the document after the command. See the POD for examples.

Caveat emptor: I've only tested this on Linux, but it *should* work on pretty much any *nix like system.

--gsiems

#!/usr/bin/perl
use strict;

open (BLACKBOARD, "+>blackboard"); #look around
no strict;
use less 'time';
my $hand = 'reluctant'; @chalk = 'obsolete';
sub cheat {print BLACKBOARD "I will not use Perl in C class\n";}
until ($caught) {
    use warnings;
    &cheat;
    $teacher_enters = int(rand(10));
    if ($teacher_enters == 1) {
        no warnings;
        $caught = "red handed";
        close BLACKBOARD;
        delete @chalk[1,2,4];
    } else {redo}
}
die "You are not to use Perl in C class, start the assignment again!";
[download]

A few months ago (end of July) we had an intrusion into an old PerlMonks database that created and continues to create an on-going discussion and strong emotions. The question I'd like to know is what material impact has the password debacle had on PerlMonks?

I'd like to know our gut feelings and I'd like to put some numbers behind that. Usually when someone has an idea for an interesting new set of site stats they code it up and then present a post to show it off. But I want to reverse the process. Before I start coding or make requests for missing information, I'd like to discuss this.

What differences have you noticed, if any? Consider site traffic volume, composition of users visiting, quality of questions and responses, number of nodes. Is there anything missing from this list? What other indicators should be considered?

Any attempt to quantify our gut observations is likely to be ambiguous at best. Numbers never tell the whole story. Worse yet, to quantify something we often need to use a proxy that only partially correlates with the behavior we want to measure.

However, observation is vulnerable to issues of salience and sometimes wishful thinking. It is human nature to see what we want to see. But even when we try to be objective, things have to catch our attention for us to observe them. We tend to give more weight to the things we care about than the things we don't. What numbers would give us objective information that we could use to counter bias in our observations?

Here are some of my preliminary ideas. I'd like to see before and after trends in the following statistics. I emphasize the word "trend" because there could be normal seasonal variations in PM traffic and I wouldn't want to confuse that with impact analysis.

• rate of new user creation.
• number of daily users by level, frequency of visit, and length of membership
• number of daily "unique visitors"
• number of anonymous monk posts
• votes per day, also by level, frequency of visit, and length of membership
• posts per day, by level

What I'd like to know is: did the exploit change the behavior of monks in any way? Is the impact, if any, primarily among experienced regular users or occassional and/or low level users?

If for example, the impact is primarly in the rate of non-spam new user creation, I would surmise that we likely have suffered significant PR damage (or we have an SEO problem). If long term members are visiting less often, voting less regularly, or posting less frequently I might worry about loss of trust in the established Perl community. I would hope that such numbers would show no statistically significant impact. But I think it is important to know, even if the results are scary or painful. If there is damage, we need to correct it. It is impossible to know the right course of action unless we understand the nature of that damage.

What do you want to know? What would you do to measure it? What implications would you draw from the data? What corrective action would that imply?

Best, beth