{"id":58248,"date":"2023-02-04T03:01:32","date_gmt":"2023-02-03T17:01:32","guid":{"rendered":"http:\/\/www.rjmprogramming.com.au\/ITblog\/?p=58248"},"modified":"2023-02-04T07:40:47","modified_gmt":"2023-02-03T21:40:47","slug":"perl-cgi-datetime-module-primer-tutorial","status":"publish","type":"post","link":"https:\/\/www.rjmprogramming.com.au\/ITblog\/perl-cgi-datetime-module-primer-tutorial\/","title":{"rendered":"Perl CGI DateTime Module Primer Tutorial"},"content":{"rendered":"
\"Perl<\/a>

Perl CGI DateTime Module Primer Tutorial<\/p><\/div>\n

Do you remember with Perl CGI Modes of Use Primer Tutorial<\/a> how we used the Perl programming language as an alternative server language player up at the RJM Programming website?<\/p>\n

Well, in any case, today, we explore some Perl modules which can make that code be more useful to us. As for how we interface to it, we’ve written a very simple HTML hello_get.html<\/a> interfacer we’d like to thank https:\/\/www.tutorialspoint.com\/perl\/perl_cgi.htm<\/a> for …<\/p>\n


\n<html>
\n<head>
\n<title>hello_get ... Thanks to https:\/\/www.tutorialspoint.com\/perl\/perl_cgi.htm and https:\/\/perlmaven.com\/most-popular-perl-modules and https:\/\/www.freecodecamp.org\/news\/how-to-format-dates-in-javascript\/<\/title>
\n<\/head>
\n<body>
\n<h1>hello_get.html HTML calls on hello_get.cgi Perl<\/h1>
\n<h3>RJM Programming - February, 2023<\/h3>
\n<h3>Thanks to https:\/\/www.tutorialspoint.com\/perl\/perl_cgi.htm<\/a> and https:\/\/perlmaven.com\/most-popular-perl-modules<\/a> and https:\/\/www.freecodecamp.org\/news\/how-to-format-dates-in-javascript\/<\/a><\/h3>
\n<br><br>
\n<FORM action = \"\/cgi-bin\/hello_get.cgi\" method = \"GET\">
\n
\n First Name: <input type = \"text\" name = \"first_name\"> <br>
\n
\n Last Name: <input type = \"text\" name = \"last_name\">
\n <input type = \"submit\" value = \"Submit\">
\n<\/FORM>
\n
\n<\/body>
\n<\/html>
\n<\/code><\/p>\n

… where this webpage’s HTML form’s action points to some Perl hello_get.cgi<\/a> (up at the Apache web server, in a cgi-bin folder and with the executable permission bit set) code using the DateTime<\/a> module, and showing the user client local timezone current time compared to this RJM Programming’s server timezone current time …<\/p>\n


\n#!\/usr\/bin\/perl
\n
\nuse DateTime;
\nuse DateTime::TimeZone;
\n
\nlocal ($buffer, @pairs, $pair, $name, $value, %FORM);
\n# Read in text
\n$ENV{'REQUEST_METHOD'} =~ tr\/a-z\/A-Z\/;
\n
\nif ($ENV{'REQUEST_METHOD'} eq \"GET\") {
\n $buffer = $ENV{'QUERY_STRING'};
\n}
\n
\n# Split information into name\/value pairs
\n@pairs = split(\/&\/, $buffer);
\n
\nforeach $pair (@pairs) {
\n ($name, $value) = split(\/=\/, $pair);
\n $value =~ tr\/+\/ \/;
\n $value =~ s\/%(..)\/pack(\"C\", hex($1))\/eg;
\n $FORM{$name} = $value;
\n}
\n
\n$first_name = $FORM{first_name};
\n$last_name = $FORM{last_name};
\n
\n$dt = DateTime->now; # same as ( epoch => time )
\n
\n$dttz = DateTime::TimeZone->new( name => 'local' )->name();
\n
\n$dt->set_time_zone( $dttz );
\n
\n$year = $dt->year;
\n$month = $dt->month; # 1-12
\n
\n$day = $dt->day; # 1-31
\n
\n$dow = $dt->day_of_week; # 1-7 (Monday is 1)
\n
\n$hour = $dt->hour; # 0-23
\n$minute = $dt->minute; # 0-59
\n
\n$second = $dt->second; # 0-61 (leap seconds!)
\n
\n$doy = $dt->day_of_year; # 1-366 (leap years)
\n
\n$doq = $dt->day_of_quarter; # 1..
\n
\n$qtr = $dt->quarter; # 1-4
\n
\n$dmy = $dt->dmy('\/'); # 06\/12\/2002
\n
\n$hms = $dt->hms; # 14:02:29
\n
\nprint \"Content-type:text\/html\\r\\n\\r\\n\";
\nprint \"<html>\";
\nprint \"<head>\";
\nprint \"<title>Hello - Second CGI Program<\/title>\";
\nprint \"<script type=text\/javascript>\";
\nprint \" function loctime() { \";
\nprint \" var qwr='' + Intl.DateTimeFormat().resolvedOptions().timeZone; \";
\nprint \" var d = new Date(); \";
\nprint \" d.toLocaleString('en-US', { timeZone: qwr }); \";
\nprint \" var ns=document.getElementById('mystime').innerHTML.split(':')[2].split(' ')[0]; \";
\nprint \" var ls=('' + d.toLocaleString()).replace(',','') + ' GMT' + d.toString().split(' GMT')[1]; \";
\nprint \" document.getElementById('mytime').innerHTML=ls.replace(':' + ls.split(':')[2].split(' ')[0] + ' ', ':' + ns + ' '); \";
\nprint \" } \";
\nprint \"<\/script>\";
\nprint \"<\/head>\";
\nprint \"<body onload=loctime();>\";
\nprint \"<h2 style='font-family:Courier New;'>Hello $first_name $last_name <br> Local: <span id=mytime><\/span><br>Server: <span id=mystime>$dmy $hms<\/span> $dttz <\/h2>\";
\nprint \"<br><br><iframe src='\/hello_get.html' style='width:100%; height:1500px;'><\/iframe><\/body>\";
\nprint \"<\/html>\";
\n
\n1;
\n<\/code><\/p>\n

The use of the HTML iframe in the Perl (writing HTML) code means that either …<\/p>\n