@tgeimer
Thanks for your solution! Saved my day ;)

Here is the carefree package :)
The python script will open the Birthday.ics file directly from your Owncloud, change the year automaticly and safe the output file at a fixed location. Python “Requests” library is used to connect to your Owncloud.
This script works in linux. The script above was only working in MS Windows.
The script can be run by cron e.g. every 30min so you will see updates and you don’t have to worry about the next year ;)

#!/usr/bin/env python
# -*- coding: utf-8 -*-

# Time functions for current year 
import time
from time import localtime, strftime

# Use Requests lib to download Owncloud Birthday calendar .ics file
import requests #http://docs.python-requests.org/en/master/

year = strftime("%Y", localtime()) #Get the current year

try: #Catch errors
	url = 'https://YOUR_URL/remote.php/dav/calendars/USER/BIRTHDAYCALENDAR?export' # Url to your Owncloud Birthday caldender .ics file. Replace parts written in capitals
	download = requests.get(url, auth=('USER', 'PASS')) #Replace parts written in capitals
	fobj_in= download.text.split("\n") #Split file
	fobj_out = open("/home/pi/MagicMirror/modules/Birthdays/geburtstage.ics","w") #Output file

	for line in fobj_in:
		if line.find("DTSTART") > -1 or line.find("DTEND") > -1: #Change year of DTSTART oder DTEND lines
			#Format of the string: DTSTART;VALUE=DATE:19650521	#DTEND;VALUE=DATE:19650522
			split=line.split(":")
			helpline=split[0]+":"+year+split[1][4:]
			fobj_out.write(helpline.encode('utf-8')+"\n")		
		else: #Change nothing, just copy the line
			fobj_out.write(line.encode('utf-8')+"\n")
	fobj_out.close() 
	download.close() 
	
except requests.exceptions.RequestException as e:  # This is the correct syntax
    print(e)

Hi Mykle1,

that is a good idea, thank you! I have a workaround now, but I need to change the files every year :(.
You can download the Birthday .ics from Owncloud and save it localy.
In the config.js file I changed the calendar url to work with local .ics file:
url: ‘webcal://localhost:8080/modules/Birthdays/geburtstage_2017.ics’, //Use a local file

Then I wrote a small python script (for Windows) to change the year of the .ics file, as you proposed above, and it worked.

If anyone is interessted you can use my python script below. It will open the “geburtstage.ics” file which needs to be located in the same folder as the python script. The script will ask for the year you want to change to and will create a new ics file containing the changed birthday years.

//your code here

**Birthday_ICS.py**
#Ask for the year you want to change to
year = input("Please enter the year you want to change to: ")

fobj_in = open("geburtstage.ics", "r") #Source file
fobj_out = open("geburtstage_" + year + ".ics","w") #Output file

for line in fobj_in:
	if line.find("DTSTART") > -1 or line.find("DTEND") > -1: #Change year of DTSTART oder DTEND lines
		#Format of the string: DTSTART;VALUE=DATE:19650521	#DTEND;VALUE=DATE:19650522
		split=line.split(":")
		helpline=split[0]+":"+year+split[1][4:]
		fobj_out.write(helpline)		
	else: #Change nothing, just copy the line
		fobj_out.write(line)
print("Complete!") #Let me know when you are finished
#Close the documents
fobj_in.close()
fobj_out.close()

Re: OwnCloud integration
Owncloud calendar integration works fine except for the birthday calendar. Magic Mirror calendar module is not showing the birthdays.
In the Owncloud Birthday calendar .ics file I found, that the birthday dates are stored with the birth year.
Example for 22MAY1965
DTSTART;VALUE=DATE:19650521
DTEND;VALUE=DATE:19650522

I assume that the calendar module is only showing entries of the current year.
Is there a workaround or module existing that could help here?

Thank you in advance.