My Holiday Calendar ics file generator

My Holiday Calendar (.ics file generator)
(Another donateWare script from MRE Software)

I was working on a Google Calendar for our ham radio club and wanted to include some holidays on it. I didn't care for the default Google Holiday offering and really wanted complete control of the holidays and descriptions. I tried modifying the Google .ics file but found that quite tedious. I decided to just write my own .ics calendar file generator and add my preferred holidays to it by taking advantage of PHP's great strtotime() function. I named it My_Holiday_Calendar.php. I saw many others on the web asking for different holiday calendars so I decided to post it on my site and let others make their own. It is a little quick and dirty coding and I am no ical expert but I have commented it pretty well and it worked great for me. Modify it, run it, and roll your own holiday calendar!

Note: The code below contains some Alabama, Mississippi, Georgia, Florida, Louisiana, and Amateur Radio events which you may want to change or remove.

Tip: You can set this up on your web server as a cron job that runs on January 1st, then subscribe to the file it generates (My_Holiday_Calendar.ics) as a URL calendar. This will keep it updated automatically until the end of the world!

This code is for informational purposes only.
USE AT YOUR OWN RISK

To download a .zip file with the .php file plus an .ics file without the state and ham holidays:

ENJOY!

<?php /* This script generates an .ics file for all the holidays I want in My Holiday Calendar This can be run as a cron job to create a fresh calendar every year and connected to Google as a URL subscription calendar */ //error_reporting(0); $path = __DIR__ . '/'; // path to files area - must be writable by the script date_default_timezone_set("America/Chicago"); $year = date("Y"); // get the current year $start_year = $year - 2; // this is the starting year - start 2 years ago $end_year = $year + 5; // This is the ending year. - end 5 years from now $remove = array(); // add events you want to remove separated by commas... $remove = array("U14", "U07"); would remove Earth Day and April Fools Day // If $remove is used the events will be removed from the calendar the next time the ics file is imported. // If you use just the value "ALL"... $remove = array("ALL"); All events will be removed the next time the calendar is imported. This is an easy way to start over! // $Vstring =""; $num = 0; for($year = $start_year; $year <= $end_year; $year++){ holarray($year); // set the $holiday array values for this year foreach($holiday as $h){ // process each holiday to make a VEVENT $uid = $h[2]."-".$year."@N4MZ.COM"; // this creates a UID for event number and year. example: U03-2028@N4MZ.COM $Vstring .= vevent($h[0], $h[1], $uid, $h[3]); $num++; // keep a count of events } } // $string = "BEGIN:VCALENDAR\r\nVERSION:2.0\r\nPRODID:-//My Holiday Calendar//iCal 1.0//EN\r\nCALSCALE:GREGORIAN\r\nMETHOD:PUBLISH\r\n"; $string .= "BEGIN:VTIMEZONE\r\nTZID:America/Chicago\r\nX-LIC-LOCATION:America/Chicago\r\nBEGIN:DAYLIGHT\r\nTZOFFSETFROM:-0600\r\nTZOFFSETTO:-0500\r\nTZNAME:CDT\r\nDTSTART:19700308T020000\r\nRRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU\r\nEND:DAYLIGHT\r\nBEGIN:STANDARD\r\nTZOFFSETFROM:-0500\r\nTZOFFSETTO:-0600\r\nTZNAME:CST\r\nDTSTART:19701101T020000\r\nRRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU\r\nEND:STANDARD\r\nEND:VTIMEZONE\r\n"; $string .= $Vstring; $string .= "END:VCALENDAR"; file_put_contents($path."My_Holiday_Calendar.ics", $string); // ics calendar file with multiple events echo "Generated ".$num." events in the file: My_Holiday_Calendar.ics<br>"; //------------------------------------------------------------------------------------------------------------- function holarray($year){ // this sets the holiday array based on the $year passed to it each time it is called global $holiday; // The array structure is Name, Description, Event Number, Unix Timestamp, Movable holiday with 1 for AL/USA and 2 for FL state holidays (2 is depreciated) // If you add an event you must give it a unique event number as it becomes part of the UID in the .ics file. // The order of the events is irrelevant. $holiday = array( array("World Amateur Radio Day", "Observance that marks the 1925 founding of the International Amateur Radio Union in Paris. The day promotes amateur radio science, highlights emergency communication capabilities, and encourages public engagement. ARRL supported!", "U00", strtotime("4/18/".$year)), array("Juneteenth", "Federal Holiday", "U01", strtotime("6/19/".$year), 1), // if it has a fifth element it is a movable friday/monday if on weekend move array("New Years Day", "Federal Holiday", "U02", strtotime("1/1/".$year), 1), array("Independence Day", "Federal Holiday", "U03", strtotime("7/4/".$year), 1), array("Rosa L. Parks Day (AL)", "State Observance in Alabama. Government offices are not closed.", "U04", strtotime("12/1/".$year)), array("Mardi Gras Starts", "Start of carnival season in the deep south.", "U05", strtotime("1/6/".$year)), array("Valentine's Day", "Observance", "U06", strtotime("2/14/".$year)), array("April Fools Day", "Observance - Ham radio use is banned on this day.", "U07", strtotime("4/1/".$year)), array("Christmas", "Federal Holiday", "U08", strtotime("12/25/".$year), 1), array("Halloween", "Observance", "U09", strtotime("10/31/".$year)), array("St. Patrick's Day", "Observance", "U10", strtotime("3/17/".$year)), array("Veteran's Day", "Federal Holiday", "U11", strtotime("11/11/".$year), 1), array("Groundhog Day", "Observance - Possum Day in Alabama", "U12", strtotime("2/2/".$year)), array("Flag Day", "Observance", "U13", strtotime("6/14/".$year)), array("Earth Day", "Observance - International", "U14", strtotime("4/22/".$year)), array("Pearl Harbor Day", "Observance - A date which will live in infamy.", "U15", strtotime("12/7/".$year)), array("Susan B. Anthony Day (FL)", "State Observance in Florida. Government offices are not closed.", "U16", strtotime("2/15/".$year), 1), array("Pascua Florida Day (FL)", "State Observance in Florida. Government offices are not closed.", "U17", strtotime("4/2/".$year), 1), array("Daylight Saving Time Starts", "Observance - Spring Forward", "U18", strtotime("second sunday of march ".$year)), array("Daylight Saving Time Ends", "Observance - Fall Back", "U19", strtotime("first sunday of november ".$year)), array("Presidents' Day", "Federal Holiday", "U20", strtotime("third monday of february ".$year)), array("Jefferson Davis Birthday (AL)", "State Holiday in Alabama. Government offices are closed.", "U21", strtotime("first monday of june ".$year)), array("Confederate Memorial Day (AL&MS)", "State Holiday in Alabama & Mississippi. Government offices are closed.", "U22", strtotime("fourth monday of april ".$year)), array("Tuskegee Airmen Day (AL)", "Observance in Alabama", "U23", strtotime("fourth thursday of march".$year)), array("Armed Forces Day", "Observance", "U24", strtotime("third saturday of may".$year)), array("The National Day of Prayer", "Observance", "U25", strtotime("first thursday of may".$year)), array("Martin Luther King Jr. Day", "Federal Holiday", "U26", strtotime("third monday of january".$year)), array("Labor Day", "Federal Holiday", "U27", strtotime("first monday of september".$year)), array("Columbus Day", "Federal Holiday", "U28", strtotime("second monday of october".$year)), array("Mother's Day", "Observance", "U29", strtotime("second sunday of may".$year)), array("Father's Day", "Observance", "U30", strtotime("third sunday of june".$year)), array("Memorial Day", "Federal Holiday", "U31", strtotime("last monday of may".$year)), array("Thanksgiving", "Federal Holiday", "U32", strtotime("fourth thursday of november".$year)), array("Mardi Gras Day", "Observed in the deep south, AKA Fat Tuesday. Mobile & Baldwin county offices are closed. State Holiday in Louisiana as is the Monday before.", "U33", get_easter_datetime($year) - (46 * 86400)), array("Good Friday (LA&GA)", "Christian holiday widely observed. State holiday in Louisiana & Georgia. Government offices are closed.", "U34", get_easter_datetime($year) - (2 * 86400)), array("Easter Sunday", "Christian holiday widely observed.", "U35", get_easter_datetime($year)), array("Atlantic Hurricane Season Starts", "Observance - The Atlantic hurricane season is the period in a year, from June 1 to November 30, when tropical or subtropical cyclones are most likely to form in the North Atlantic Ocean.", "U36", strtotime("6/1/".$year)), array("Atlantic Hurricane Season Ends", "Observance - The Atlantic hurricane season runs from June 1 to November 30 which is when tropical or subtropical cyclones are most likely to form in the North Atlantic Ocean.", "U37", strtotime("11/30/".$year)), array("Black Friday (FL&GA)", "State Holiday in Florida & Georgia. Government offices are closed.", "U38", strtotime("+1 day fourth thursday of november".$year)), array("Battle of New Orleans (LA)", "State Holiday in Louisiana. Government offices are closed.", "U39", strtotime("1/8/".$year)), array("Election Day", "Observance - Occurs on Tuesday after the first Monday in November.", "U40", strtotime("+1 day first monday of november".$year)), array("National Radio Day", "Observance - National Radio Day is celebrated annually to honor the invention of the radio and its enduring impact on mass communication, news, and entertainment.", "U41", strtotime("8/20/".$year)) ); // move federal and some state holidays to friday or monday if they occur on a weekend for($i=0; $i<count($holiday); $i++){ if(isset($holiday[$i][4])){ // if it has a 5th element it is a correctable holiday $orgDate = date('F jS', $holiday[$i][3]); if(date('D', $holiday[$i][3]) == "Sat" && $holiday[$i][4] == 1){ // only correct saturdays if this is set to 1 $holiday[$i][3] = $holiday[$i][3] - 86400; // Federal Holiday sat=fri $holiday[$i][0] = $holiday[$i][0] . " <--"; $holiday[$i][1] = $holiday[$i][1] . " <-- Observed on Friday because of the weekend occurance of {$orgDate}."; } else if(date('D', $holiday[$i][3]) == "Sun"){ $holiday[$i][3] = $holiday[$i][3] + 86400; // Federal Holiday sun=mon $holiday[$i][0] = "--> " . $holiday[$i][0]; $holiday[$i][1] = $holiday[$i][1] . " --> Observed on Monday because of the weekend occurance of {$orgDate}."; } } } } //--------- function get_easter_datetime($year) { $base = strtotime("21 March ".$year); $days = easter_days($year); return $base + ($days * 86400); // return unix timestamp for easter } //----------------- function vevent($summary, $desc, $uid, $timestamp){ // this returns a string containing a VEVENT global $remove; // $string = "BEGIN:VEVENT\r\n"; $string .= "DTSTART;VALUE=DATE:" . date('Ymd', $timestamp) . "\r\n"; $string .= "DTEND;VALUE=DATE:" . date('Ymd', $timestamp + 86400) . "\r\n"; // add one day to the start date $string .= "DTSTAMP:" . gmdate('Ymd\THis\Z') . "\r\n"; // $ptr = strpos($uid, "-"); if(isset($remove[0])){ if(in_array(substr($uid, 0, $ptr), $remove) || $remove[0] == "ALL") $string .= "STATUS:CANCELLED\r\n"; // if this is on the list to remove else $string .= "STATUS:CONFIRMED\r\n"; } else $string .= "STATUS:CONFIRMED\r\n"; $string .= "SUMMARY:" . $summary . "\r\n"; $desc = foldIcsLine($desc); // fold long description line lengths at 75 characters $string .= "DESCRIPTION:" . $desc ."\r\n"; $string .= "UID:".$uid."\r\n"; $string .= "CLASS:PUBLIC\r\n"; $string .= "TRANSP:OPAQUE\r\n"; // $string .= "END:VEVENT\r\n"; return $string; } //------------------------- function foldIcsLine($string) { // this limits the line length to 75 characters to meet the standard // Escape standard ics characters first $string = str_replace(["\r\n", "\r", "\n"], '\n', $string); $string = str_replace(['\\', ',', ';'], ['\\\\', '\,', '\;'], $string); $lines = []; $encodingPrefixLength = 12; // Adjust if your line has a prefix like "DESCRIPTION:" // Split the string into chunks of 75 bytes or less while (strlen($string) > 0) { $maxLength = 75 - $encodingPrefixLength; // Take a chunk $chunk = substr($string, 0, $maxLength); $lines[] = $chunk; $string = substr($string, strlen($chunk)); // After the first line, subsequent lines require 1 space for indentation $encodingPrefixLength = 1; } // Join lines with CRLF and a single space for continuation return implode("\r\n ", $lines); } ?>

If you find this code of value, donate a little to the cause. Think of the time you just saved!

USE AT YOUR OWN RISK!

Feedback on this script is welcomed.

Questions / Comments? Email me.