date_api_ical.inc in Date 5
Same filename and directory in other branches
Parse iCal imports and create iCal exports. This file must be included when these functions are needed.
File
date_api_ical.incView source
<?php
/**
* @file
* Parse iCal imports and create iCal exports.
* This file must be included when these functions are needed.
*/
/**
* Turn an array of events into a valid iCalendar file
*
* @param $events
* An array of events where each event is an array with:
* 'start' => local start date as unix timestamp,
* omit time for all day event.
* 'end' => local end date as unix timestamp,
* optional, omit for all day event.
* 'timezone' => name of the timezone for the event,
* blank for stateless events.
* 'summary' => Title of event (Text)
* 'description' => Description of event (Text)
* 'location' => Location of event (Text)
* 'uid' => ID of the event for use by calendaring program.
* Recommend the url of the node
* 'url' => URL of event information
*
* @param $calname
* Name of the calendar. Will use site name if none is specified.
*
* @return
* Text of a date_icalendar file.
*
* @todo
* add folding and more ical elements
*/
function date_ical_export($events, $calname = NULL) {
$output .= "BEGIN:VCALENDAR\nVERSION:2.0\n";
$output .= "METHOD:PUBLISH\n";
$output .= 'X-WR-CALNAME:' . date_ical_escape_text($calname ? $calname : variable_get('site_name', '')) . "\n";
$output .= "PRODID:-//Drupal iCal API//EN\n";
foreach ($events as $uid => $event) {
// Skip any items with empty dates.
if (!empty($event['start'])) {
$output .= "BEGIN:VEVENT\n";
$output .= "DTSTAMP;VALUE=DATE-TIME:" . gmdate("Ymd\\THis\\Z", time()) . "\n";
$tz_append = '';
if ($event['timezone'] == 'GMT' || $event['timezone'] == 'UTC') {
$tz_append = 'Z';
}
if (empty($event['timezone']) || $tz_append) {
$output .= "DTSTART;VALUE=DATE-TIME:" . gmdate("Ymd\\THis", $event['start']) . $tz_append . "\n";
}
else {
$output .= "DTSTART;TZID=" . $event['timezone'] . ":" . gmdate("Ymd\\THis", $event['start']) . "\n";
}
if ($event['start'] && $event['end']) {
if (empty($event['timezone']) || $tz_append) {
$output .= "DTEND;VALUE=DATE-TIME:" . gmdate("Ymd\\THis", $event['end']) . $tz_append . "\n";
}
else {
$output .= "DTEND;TZID=" . $event['timezone'] . ":" . gmdate("Ymd\\THis", $event['end']) . "\n";
}
}
$output .= "UID:" . ($event['uid'] ? $event['uid'] : $uid) . "\n";
if ($event['url']) {
$output .= "URL;VALUE=URI:" . $event['url'] . "\n";
}
if ($event['location']) {
$output .= "LOCATION:" . date_ical_escape_text($event['location']) . "\n";
}
$output .= "SUMMARY:" . date_ical_escape_text($event['summary']) . "\n";
if ($event['description']) {
$output .= "DESCRIPTION:" . date_ical_escape_text($event['description']) . "\n";
}
$output .= "END:VEVENT\n";
}
}
$output .= "END:VCALENDAR\n";
return $output;
}
/**
* Escape #text elements for safe iCal use
*
* @param $text
* Text to escape
*
* @return
* Escaped text
*
*/
function date_ical_escape_text($text) {
//$text = strip_tags($text);
$text = str_replace('"', '\\"', $text);
$text = str_replace("\\", "\\\\", $text);
$text = str_replace(",", "\\,", $text);
$text = str_replace(":", "\\:", $text);
$text = str_replace(";", "\\;", $text);
$text = str_replace("\n", "\n ", $text);
return $text;
}
/**
* Return an array of iCalendar information from an iCalendar file.
*
* No timezone adjustment is performed in the import since the timezone
* conversion needed will vary depending on whether the value is being
* imported into the database (when it needs to be converted to UTC), is being
* viewed on a site that has user-configurable timezones (when it needs to be
* converted to the user's timezone), if it needs to be converted to the
* site timezone, or if it is a date without a timezone which should not have
* any timezone conversion applied.
*
* Properties that have dates and times are converted to sub-arrays like:
* 'datetime' => date in YYYY-MM-DD HH:MM format, not timezone adjusted
* 'all_day' => whether this is an all-day event
* 'tz' => the timezone of the date, could be blank for absolute
* times that should get no timezone conversion.
*
* Exception dates can have muliple values and are returned as arrays
* like the above for each exception date.
*
* Most other properties are returned as PROPERTY => VALUE.
*
* Each item in the VCALENDAR will return an array like:
* [0] => Array (
* [TYPE] => VEVENT
* [UID] => 104
* [SUMMARY] => An example event
* [URL] => http://example.com/node/1
* [DTSTART] => Array (
* [datetime] => 1997-09-07 09:00:00
* [all_day] => 0
* [tz] => US/Eastern
* )
* [DTEND] => Array (
* [datetime] => 1997-09-07 11:00:00
* [all_day] => 0
* [tz] => US/Eastern
* )
* [RRULE] => Array (
* [FREQ] => Array (
* [0] => MONTHLY
* )
* [BYDAY] => Array (
* [0] => 1SU
* [1] => -1SU
* )
* )
* [EXDATE] => Array (
* [0] = Array (
* [datetime] => 1997-09-21 09:00:00
* [all_day] => 0
* [tz] => US/Eastern
* )
* [1] = Array (
* [datetime] => 1997-10-05 09:00:00
* [all_day] => 0
* [tz] => US/Eastern
* )
* )
* )
*
* @param $filename
* Location (local or remote) of a valid iCalendar file
* @return array
* An array with all the elements from the ical
* @todo
* figure out how to handle this if subgroups are nested,
* like a VALARM nested inside a VEVENT.
*/
function date_ical_import($filename) {
$items = array();
include_once './' . drupal_get_path('module', 'date_api') . '/date.inc';
// Fetch the iCal data. If file is a URL, use drupal_http_request. fopen
// isn't always configured to allow network connections.
if (substr($filename, 0, 4) == 'http') {
// Fetch the ical data from the specified network location
$icaldatafetch = drupal_http_request($filename);
// Check the return result
if ($icaldatafetch->error) {
drupal_set_message('Request Error: ' . $icaldatafetch->error, 'error');
return array();
}
// Break the return result into one array entry per lines
$icaldatafolded = explode("\n", $icaldatafetch->data);
}
else {
$icaldatafolded = @file($filename, FILE_IGNORE_NEW_LINES);
if ($icaldatafolded === FALSE) {
drupal_set_message('Failed to open file: ' . $filename, 'error');
return array();
}
}
// Verify this is iCal data
if (trim($icaldatafolded[0]) != 'BEGIN:VCALENDAR') {
drupal_set_message('Invalid calendar file:' . $filename, 'error');
return array();
}
// "unfold" wrapped lines
$icaldata = array();
foreach ($icaldatafolded as $line) {
$out = array();
// See if this looks like the beginning of a new property or value.
// If not, it is a continuation of the previous line.
ereg("([A-Z]+)[:|;](.*)", $line, $out);
if (empty($out)) {
$line = array_pop($icaldata) . "\n" . $line;
}
$icaldata[] = $line;
}
$icaldatafolded = NULL;
// Parse the iCal information
$is_subgroup = FALSE;
$skip = FALSE;
foreach ($icaldata as $line) {
$line = trim($line);
$vcal .= $line . "\n";
switch ($line) {
case 'BEGIN:VEVENT':
case 'BEGIN:VALARM':
case 'BEGIN:VTODO':
case 'BEGIN:VJOURNAL':
case 'BEGIN:VVENUE':
case 'BEGIN:VFREEBUSY':
case 'BEGIN:VTIMEZONE':
unset($subgroup);
$type = str_replace('BEGIN:', '', $line);
$subgroup['TYPE'] = $type;
$is_subgroup = TRUE;
break;
case 'END:VEVENT':
case 'END:VALARM':
case 'END:VTODO':
case 'END:VJOURNAL':
case 'END:VVENUE':
case 'END:VFREEBUSY':
case 'END:VTIMEZONE':
// Can't be sure whether DTSTART is before or after DURATION,
// so parse DURATION at the end.
if (array_key_exists('DURATION', $subgroup)) {
date_ical_parse_duration($subgroup);
}
// Check for all-day events.
if (array_key_exists('DTSTART', $subgroup) && !array_key_exists(DTEND, $subgroup)) {
$subgroup['DTSTART']['all_day'] = 1;
}
$items[] = $subgroup;
unset($subgroup);
$is_subgroup = FALSE;
break;
default:
unset($field, $data, $prop_pos, $property);
ereg("([^:]+):(.*)", $line, $reg);
$field = $reg[1];
$data = $reg[2];
$property = $field;
$prop_pos = strpos($property, ';');
if ($prop_pos !== false) {
$property = substr($property, 0, $prop_pos);
}
$property = strtoupper(trim($property));
switch ($property) {
// Keep blank lines out of the results.
case '':
break;
// Lots of properties have date values that must be parsed out.
case 'CREATED':
case 'LAST-MODIFIED':
case 'DTSTART':
case 'DTEND':
case 'DTSTAMP':
case 'RDATE':
case 'TRIGGER':
case 'FREEBUSY':
case 'DUE':
case 'COMPLETED':
if (!$is_subgroup) {
$items[$property] = date_ical_parse_date($field, $data);
}
else {
$subgroup[$property] = date_ical_parse_date($field, $data);
}
break;
case 'EXDATE':
$subgroup[$property] = date_ical_parse_exceptions($field, $data);
break;
case 'DURATION':
// Can't be sure whether DTSTART is before or after DURATION in
// the VEVENT, so store the data and parse it at the end.
$subgroup['DURATION'] = array(
'DATA' => $data,
);
break;
case 'RRULE':
case 'EXRULE':
$subgroup[$property] = date_ical_parse_rule($field, $data);
break;
case 'SUMMARY':
case 'DESCRIPTION':
case 'LOCATION':
$subgroup[$property] = date_ical_parse_text($field, $data);
break;
// For all other properties, just store the property and the value.
// This can be expanded on in the future if other properties should
// be given special treatment.
default:
if (!$is_subgroup) {
$items[$property] = $data;
}
else {
$subgroup[$property] = $data;
}
break;
}
}
}
// Store the original text in the array for reference.
$items['VCALENDAR'] = $vcal;
return $items;
}
/**
* Parse a ical date element.
*
* Possible formats to parse include:
* PROPERTY:YYYYMMDD[T][HH][MM][SS][Z]
* PROPERTY;VALUE=DATE:YYYYMMDD[T][HH][MM][SS][Z]
* PROPERTY;VALUE=DATE-TIME:YYYYMMDD[T][HH][MM][SS][Z]
* PROPERTY;TZID=XXXXXXXX;VALUE=DATE:YYYYMMDD[T][HH][MM][SS]
* PROPERTY;TZID=XXXXXXXX:YYYYMMDD[T][HH][MM][SS]
*
* The property and the colon before the date are removed in the import
* process above and we are left with $field and $data.
*
* @param $field
* The text before the colon and the date, i.e.
* ';VALUE=DATE:', ';VALUE=DATE-TIME:', ';TZID='
* @param $data
* The date itself, after the colon, in the format YYYYMMDD[T][HH][MM][SS][Z]
* 'Z', if supplied, means the date is in UTC.
*
* @return array
* $items array, consisting of:
* 'datetime' => date in YYYY-MM-DD HH:MM format, not timezone adjusted
* 'all_day' => whether this is an all-day event with no time
* 'tz' => the timezone of the date, could be blank if the ical
* has no timezone; the ical specs say no timezone
* conversion should be done if no timezone info is
* supplied
* @todo
* Another option for dates is the format PROPERTY;VALUE=PERIOD:XXXX. The period
* may include a duration, or a date and a duration, or two dates, so would
* have to be split into parts and run through date_ical_parse_date() and
* date_ical_parse_duration(). This is not commonly used, so ignored for now.
* It will take more work to figure how to support that.
*/
function date_ical_parse_date($field, $data) {
$tz = '';
$data = trim($data);
$items = array(
'DATA' => $data,
);
if (substr($data, -1) == 'Z') {
$tz = 'UTC';
}
if (strstr($field, 'TZID=')) {
$tmp = explode('=', $field);
// Fix commonly used alternatives like US-Eastern which should be US/Eastern.
$tz = str_replace('-', '/', $tmp[1]);
}
$data = str_replace(array(
'T',
'Z',
), '', $data);
preg_match(DATE_REGEX_LOOSE, $data, $regs);
if (!empty($regs[5])) {
$time = ' ' . date_pad($regs[5]) . ':' . date_pad($regs[6]) . ':' . date_pad($regs[7]);
}
$items['datetime'] = $regs[1] . '-' . $regs[2] . '-' . $regs[3] . $time;
$items['all_day'] = empty($time) ? 1 : 0;
$items['tz'] = $tz;
$items['granularity'] = empty($time) ? array(
'Y',
'M',
'D',
) : array(
'Y',
'M',
'D',
'H',
'N',
'S',
);
return $items;
}
/**
* Parse an ical repeat rule.
*
* @return array
* Array in the form of PROPERTY => array(VALUES)
* PROPERTIES include FREQ, INTERVAL, COUNT, BYDAY, BYMONTH, BYYEAR, UNTIL
*/
function date_ical_parse_rule($field, $data) {
$items = array(
'DATA' => $data,
);
$rule = explode(';', $data);
foreach ($rule as $key => $value) {
$param = explode('=', $value);
if ($param[0] == 'UNTIL') {
$values = date_ical_parse_date('', $param[1]);
}
else {
$values = explode(',', $param[1]);
}
$items[$param[0]] = $values;
}
return $items;
}
/**
* Parse exception dates (can be multiple values).
*
* @return array
* an array of date value arrays.
*/
function date_ical_parse_exceptions($field, $data) {
$items = array(
'DATA' => $data,
);
$ex_dates = explode(',', $data);
foreach ($ex_dates as $ex_date) {
$items[] = date_ical_parse_date('', $ex_date);
}
return $items;
}
/**
* Parse the duration of the event.
*
* Example:
* DURATION:PT1H30M
* DURATION:P1Y2M
*
* @param $subgroup
* array of other values in the vevent so we can
* check for DTSTART and add DTEND.
*/
function date_ical_parse_duration(&$subgroup) {
$items = $subgroup['DURATION'];
$data = $items['DATA'];
preg_match('/^P(\\d{1,4}[Y])?(\\d{1,2}[M])?(\\d{1,2}[W])?(\\d{1,2}[D])?([T]{0,1})?(\\d{1,2}[H])?(\\d{1,2}[M])?(\\d{1,2}[S])?/', $data, $duration);
$items['year'] = str_replace('Y', '', $duration[1]);
$items['month'] = str_replace('M', '', $duration[2]);
$items['week'] = str_replace('W', '', $duration[3]);
$items['day'] = str_replace('D', '', $duration[4]);
$items['hour'] = str_replace('H', '', $duration[6]);
$items['minute'] = str_replace('M', '', $duration[7]);
$items['second'] = str_replace('S', '', $duration[8]);
$start_date = array_key_exists('DTSTART', $subgroup) ? $subgroup['DTSTART']['datetime'] : date_unix2iso(date_time());
$timezone = array_key_exists('DTSTART', $subgroup) ? $subgroup['DTSTART']['tz'] : variable_get('date_default_timezone_name', 'UTC');
$date = date_make_date(str_replace(' ', 'T', $start_date), $timezone, 'local');
$stamp1 = $date->local->timestamp;
$stamp2 = $stamp1;
foreach ($items as $item => $count) {
if ($count > 0) {
$stamp2 = strtotime('+' . $count . ' ' . $item, $stamp2);
}
}
$format = date_limit_format('Y-m-d H:i:s', $subgroup['DTSTART']['granularity']);
$subgroup['DTEND'] = array(
'datetime' => date_format_date($format, $stamp2, NULL, $timezone),
'all_day' => $subgroup['DTSTART']['all_day'],
'tz' => $timezone,
);
$items['DURATION'] = $stamp2 - $stamp1;
$subgroup['DURATION'] = $items;
}
/**
* Parse and clean up ical text elements.
*/
function date_ical_parse_text($field, $data) {
if (strstr($field, 'QUOTED-PRINTABLE')) {
$data = quoted_printable_decode($data);
}
$data = str_replace('\\n', "\n", $data);
$data = stripslashes($data);
return $data;
}
/**
* Adjust ical date to appropriate timezone and format it.
*
* @param $ical_date
* an array of ical date information created in the ical import.
* @param $to_tz
* the timezone to convert the date's value to.
* @return object
* a timezone-adjusted date object
*/
function date_ical_date($ical_date, $to_tz = FALSE) {
// If the ical date has no timezone, must assume it is stateless
$from_tz = $ical_date['tz'];
// Convert this to an ISO date;
$ical_date['datetime'] = str_replace(' ', 'T', $ical_date['datetime']);
$date = date_make_date($ical_date['datetime'], $from_tz, 'local');
if ($ical_date['tz'] != '' && $to_tz != $ical_date['tz']) {
date_convert_timezone($date, $from_tz, $to_tz, 'local');
}
return $date;
}Functions
Name |
Description |
|---|---|
| date_ical_date | Adjust ical date to appropriate timezone and format it. |
| date_ical_escape_text | Escape #text elements for safe iCal use |
| date_ical_export | Turn an array of events into a valid iCalendar file |
| date_ical_import | Return an array of iCalendar information from an iCalendar file. |
| date_ical_parse_date | Parse a ical date element. |
| date_ical_parse_duration | Parse the duration of the event. |
| date_ical_parse_exceptions | Parse exception dates (can be multiple values). |
| date_ical_parse_rule | Parse an ical repeat rule. |
| date_ical_parse_text | Parse and clean up ical text elements. |