CGI and Perl

Adding Calendar Entries with add_date.cgi

The add_date.cgi program either outputs an HTML form to set up a new appointment or takes the post-method URI encoded data from the form and inputs it into the database (see Listing 11.4). Like hypercal.cgi, which action occurs is based on the input supplied to the program in the URI.

Listing 11.4. add_date.cgi.

#!/usr/bin/perl
 #
 #    Add Date
 #
 #    Prints html form for input of new appointment.  Sends the
 #  form input to part_2 for processing.
 #    Richard Bowen, 12/14/95
 #    rbowen@aiclex.com
 #_____________________________________________________
 require `httools.pl';
 require `variables';
 &header;
 # Determine if it is a personal calendar
 ($sub=$ENV{`PATH_INFO'})=~s#^/##;
 if ($sub=~/personal/){require $personal};
 #  Read in date from QUERY_STRING
 $date=$ENV{`QUERY_STRING'};
 ($month,$day,$year,$command)=split(/&/,$date);
 #
 #    Determine which part of the script is being called
 #__________________________________
 if ($command eq "doit") {&part_2}
 else { &part_1 };
 #
 #    Part One
 #
 #    Prints html form and sends results to part 2
 #______________________________________________
 sub part_1    {
 #  Print some titles to browser.
 &month_txt("$month");
 &title ("Add an appointment for $month_txt $day, $year.");
 print <<"HTML";
 <h2>Add an appointment for $month_txt $day, $year.</h2>
 <b>Note:</b> Only authorized users will be able to add and delete
 appointments. Please contact your web adminstrator for a username
 and password.
 <hr>
 <form method=post action=$base_url$add_date?$month&$day&$year&doit>
 <b>Time:</b>
 <input name="hour" size=2 value="00"><b>: </b>
 <input name="min" value="00" size=2>
 <input type=radio name="ampm" value="am" CHECKED>AM
 <input type=radio name="ampm" value="pm">PM
 <br>
 <b>Until:</b>
 <input name="hour_done" size=2 value="00"><b>: </b>
 <input name="min_done" value="00" size=2>
 <input type=radio name="ampm_done" value="am" CHECKED>AM
 <input type=radio name="ampm_done" value="pm">PM
 <br>
 <i>If no beginning time is specified, the event will be listed as
 the whole day.  If no end time is entered, the event will be listed
 with only the beginning time</i>
 <br>
 <b>Description</b><br>
 <textarea name="desc" rows=5 cols=60></textarea><br>
 <table><tr><td valign=top rowspan=5><b>Event occurs:</b><br>
 <td><input type=radio name="freq" value="once" CHECKED>Once<br>
 <tr><td><input type=radio name="freq" value="daily">Daily for :
 <input name="days" value="1" size="2"> days.<br>
 <tr><td><input type=radio name="freq" value=\"weekly\">Weekly for :
 <input name="weeks" value="1" size=2> weeks.<br>
 <tr><td><input type=radio name="freq" value="monthly">Monthly for :
 <input name="months" value="1" size=2> months.<br>
 <tr><td><input type=radio name="freq" value="annual">Annually for :
 <input name="years" value="1" size=2> years.<br>
 </table>
 Please enter your name : <input name="perp" size="20"><br>
 <input type=submit value="Add Appointment">
 </form><hr>
 Calendar entries will expire and be deleted $old days after the event.
 HTML
 &footer;
     }        #  End of part 1
 sub part_2    {
 #    Receives the post data from add_form and adds the information
 #  to the database.  Format of database is currently:
 #  Julean&time&endtime&event&name&id
 #
 # Get data from form post.
 #  Variables are:
 #  hour, min, ampm, desc, freq, perp
 #  hour_done, min_done, ampm_done, days, weeks, months
 #  freq = one of (once, daily, weekly, monthly)
 &form_parse;
 # Strip returns from description field to make it one continuous string.
 $FORM{`desc'} =~ s/\n//g;
 #  Print titles to HTML page.
 &month_txt("$month");
 &title ("Appointment added to $month_txt $day, $year");
 print "<h1>Appointment added to $month_txt $day, $year</h1>";
 #  Read in current contents of database.
 open (DATES,"$datebook") || print "Was unable to open the datebook
                                    database for reading <br>\n";
 @dates=<DATES>;
 close DATES;
 for (@dates){chop};
 &julean($month,$day,$year);
 #    Rewrite time
 &time($FORM{`hour'},$FORM{`min'},$FORM{`ampm'});
 $begin=$time;
 &time($FORM{`hour_done'},$FORM{`min_done'},$FORM{`ampm_done'});
 $done=$time;
 # Get id number
 open (ID, "$hypercal_id")  || print "Was unable to open the ID file for reading<br>\n";
 @id=<ID>;
 close ID;
 for (@id){chop};
 @id[0]++;
 if (@id[0]>=999999) {@id[0]=1};
 $id=@id[0];
 open (NEWID,">$hypercal_id")  || print "Was unable to open the ID
                                         file ($hypercal_id) for writing<br>\n";
 for $each (@id)    {
 print NEWID "$each\n";}
 #  Add the new appointment to the database.
 $newappt="$jule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";
 push (@newdates,$newappt);
 if ($FORM{`freq'} ne "once") { &many };
 &julean($month,$day,$year);
 &todayjulean;
 for $date (@dates)    {
 ($juldate,$apptime,$appendtime,$appdesc,$perpname,$id)=split(/~~~/,$date);
 if (($today-$juldate)<=$old) {push (@newdates,$date) }
         }
 @dates=sort(@newdates);
 #  Write database back to disk file.
 open (NEWDATES,">$datebook") || print "Was unable to open the
                                        datebook file for writing.<br>\n";
 foreach $date (@dates) {print NEWDATES "$date\n"}
 close NEWDATES;
 #  Links back to other pages.
 print "Back to calendar for
        <a href=$base_url$hypercal?$month&$year>$month\/$year</a><br>";
 print "Back to <a href=$base_url$disp_day?$month&$day&$year>
        $month\/$day\/$year</a>.";
 &footer;
         }    # End of part_2
 #
 #    Sub time
 #  Rewrites time into 24hr format.
 #
 sub time    {
 $time="";
 $HOUR=$_[0];
 $MINS=$_[1];
 $merid=$_[2];
 if ($merid eq "pm") {
  $HOUR+=12;
  if ($HOUR==24) {$HOUR=12}
         }
 if ($HOUR==12 && $merid eq "am"){$HOUR=24};
 if ($HOUR>24){$HOUR=23};
 if ($MINS>59){$MINS=59};
 $HOUR=sprintf "%02.00f",$HOUR;
 $MINS=sprintf "%02.00f",$MINS;
 $time=$HOUR.":".$MINS;
         }
 #
 #    If frequency is more than once ...
 #____________________________________________________
 sub many    {
 MANY:    {
     &daily, last MANY if ($FORM{`freq'} eq "daily");
     &weekly, last MANY if ($FORM{`freq'} eq "weekly");
     &monthly, last MANY if ($FORM{`freq'} eq "monthly");
     &annual, last MANY if ($FORM{`freq'} eq "annual");
     }
 open (ID, ">$hypercal_id");
 @id[0]=$id;
 for $each(@id)    {
 print ID "$each\n";}
         }
 sub daily {
 #    For daily appointments for $FORM{`days'} days
 $days=$FORM{`days'};
 for ($i=1; $i<$days; $i++)    {
 $newjule=($jule+$i);
 $id++;
 $newappt="$newjule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";
 push (@newdates, $newappt);
                 }  #  endfor
 }    #    End daily
 sub weekly {
 #    For weekly appointments for $FORM{`weeks'} weeks.
 $weeks=$FORM{`weeks'};
 if ($weeks>156){$weeks=156};
 for ($i=1;$i<$weeks;$i++)    {
 $newjule=($jule+(7*$i));
 $id++;
 $newappt="$newjule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";
 push (@newdates, $newappt);
                 }  #endfor
 }   #    End weekly
 sub annual    {
 #  for annual appointments for $FORM{`years'} years.
 $years=$FORM{`years'};
 if ($years>10){$years=10};
 for ($i=1;$i<$years;$i++)    {
 $some_year=($year+$i);
 &julean($month,$day,$some_year);
 $id++;
 $newappt="$jule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";
 push (@newdates, $newappt);
                 }  #end for
 }   #   End annual
 sub monthly {
 #    For monthly appointments for $FORM{`months'} months
 #    This is the more difficult one
 #________________________________________
 $months=$FORM{`months'};
 if ($months>36) {$months=36};
 $this_month=$month;
 $this_year=$year;
 $this_day=$day;
 for ($i=1;$i<$months;$i++)    {
 $this_month++;
 if ($this_month==13)    {$this_month=1;
             $this_year++;}
 #  Check to see if this is a last-day-of-the-month thing
 $this_day=$day;
 if ($this_day>=28) { &last_days };
 &julean($this_month,$this_day,$this_year);
 $newjule=$jule;
 $id++;
 $newappt="$newjule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";
 push (@newdates, $newappt);
                 } #  Endfor
 }
 sub last_days    {
 #
 #    If the day given is more than the days in the month,
 #    it is reset to the last day of the month
 #______________________________________________________
 SWITCH:     {
     $last=31, last SWITCH if ($this_month==1);
     $last=28, last SWITCH if ($this_month==2);
     $last=31, last SWITCH if ($this_month==3);
     $last=30, last SWITCH if ($this_month==4);
     $last=31, last SWITCH if ($this_month==5);
     $last=30, last SWITCH if ($this_month==6);
     $last=31, last SWITCH if ($this_month==7);
     $last=31, last SWITCH if ($this_month==8);
     $last=30, last SWITCH if ($this_month==9);
     $last=31, last SWITCH if ($this_month==10);
     $last=30, last SWITCH if ($this_month==11);
     $last=31, last SWITCH if ($this_month==12);
     }
 if ($this_day>$last) {$this_day=$last};
 }

The code is broken down into two parts. The following lines of code determine which part of the script to run based on the presence of a variable supplied to the script at runtime:

$date=$ENV{`QUERY_STRING'};
 ($month,$day,$year,$command)=split(/&/,$date);
 if ($command eq "doit") {&part_2}
 else { &part_1 };

The first part (Part 1) of the code in add_date.cgi simply prints out the HTML form used to
input a new appointment, then exits. Part 2 takes the data supplied in the HTML form in Part 1 and adds it to the database. The following code assembles a new database entry into $newappt, based on information supplied by the post of the form:

 $newappt="$jule~~~$begin~~~$done~~~$FORM{`desc'}~~~$FORM{`perp'}~~~$id";

If there were multiple occurrences of the same event specified in the form, the following code would create an array @dates based on the specified frequency of the event (daily, weekly, monthly, and so on). The database file is opened as a new file handle (NEWDATES). Then, the database, contained in @dates, is sorted and saved back to disk.

push (@newdates,$newappt);
 if ($FORM{`freq'} ne "once") { &many };
 &julean($month,$day,$year);
 &todayjulean;
 for $date (@dates)    {
 ($juldate,$apptime,$appendtime,$appdesc,$perpname,$id)=split(/~~~/,$date);
 if (($today-$juldate)<=$old) {push (@newdates,$date) }
         }
 @dates=sort(@newdates);
 #  Write database back to disk file.
 open (NEWDATES,">$datebook") || print "Was unable to open the
                                        datebook file for writing.<br>\n";
 foreach $date (@dates) {print NEWDATES "$date\n"}
 close NEWDATES;

by BrainBellupdated
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