Can't get crontab to work properly, trying to start a python script on boot

Question

I am trying to start a python script when the raspberry boots up. I have set up a new job in crontab, but it does not work liek expected. Here is what I did:

My script is in the following directory:

/home/pi/MyProgram/MyProgram.py

Then I made it executable by typing:

cd /home/pi/MyProgram
sudo chmod +x MyProgram.py

Than I added a job to crontab by:

sudo crontab -e

I added this line:

@reboot sleep 60 && sudo python /home/pi/MyProgram/MyProgram.py 2>&1 >>/home/pi/MyProgram/log.txt

I need the 60 seconds sleep, cause of some services starting later, like mqtt. After a reboot (and some seconds of waiting, because of the sleep 60) the display gets black for a second, but than returns to the desktop. Getting black for a second is a sign for me that the script tries to start. The script initializes pygame as one of the first steps.

The logfile log.txt remains empty.

What is possibly wrong? Do I oversee something?

NOTE: Running the script in the terminal with sudo python /home/pi/MyProgram/MyProgram.py works like a charm.

NOTE2: journalctl gives the following lines about cron:

cron[428]: (CRON) INFO (pidfile fd = 3)
...
cron[428]: (CRON) INFO (Running @reboot jobs)
CRON[451]: pam_unix(cron:session): session opened for user root by (uid=0)
...
CRON[464]: (root) CMD (sleep 60 && sudo python /home/pi/MyProgram/MyProgram.py 2>&1 >>/home/pi/MyProgram/log.txt)

Answer 1

To log any output:

sleep 60
python /home/pi/MyProgram/MyProgram.py >>/home/pi/MyProgram/log.txt 2>&1

Perhaps:

ZZZ=""
while [ -z "$ZZZ" ]
do
  sleep 5
  ZZZ="$(ps -ef | grep mqtt)"
done
python /home/pi/MyProgram/MyProgram.py >>/home/pi/MyProgram/log.txt 2>&1

if your script needs "mqtt" running

Answer 2

I think you need a full path to Python... try /usr/bin/python, or python3 if that's what you need.