plot-schedule for Debian12 fails and generates cache_timeout error

[szymontrocha]

Seems like plot-schedule doesn't work for Debian 12. Running pscheduler plot-schedule -PT6H > schedule.png produces empty PNG file. This is testpoint bundle:

# cat /etc/issue
Debian GNU/Linux 12 \n \l
# apt list perfsonar-testpoint
Listing... Done
perfsonar-testpoint/perfsonar-release,now 5.1.4 all [installed]

2025-01-02T10:09:42.443022+01:00 perfsonar1 pscheduler-api[4052507] ERROR    Exception: TypeError: send_file() got an unexpected keyword argument 'cache_timeout'
2025-01-02T10:09:42.443304+01:00 perfsonar1 pscheduler-api[4052507] ERROR    Traceback (most recent call last):
2025-01-02T10:09:42.443445+01:00 perfsonar1 pscheduler-api[4052507] ERROR      File "/usr/share/pscheduler/api-server/pschedulerapiserver/schedule.py", line 220, in schedule
2025-01-02T10:09:42.443549+01:00 perfsonar1 pscheduler-api[4052507] ERROR        return send_file(image_path, cache_timeout=1)
2025-01-02T10:09:42.443674+01:00 perfsonar1 pscheduler-api[4052507] ERROR               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2025-01-02T10:09:42.443774+01:00 perfsonar1 pscheduler-api[4052507] ERROR    TypeError: send_file() got an unexpected keyword argument 'cache_timeout'
2025-01-02T10:09:42.444183+01:00 perfsonar1 pscheduler-api[4052507] ERROR    Internal error 150.254.163.209 GET https://perfsonar1/pscheduler/schedule: Unable to plot schedule; see system logs. send_file() got an unexpected keyword argument 'cache_timeout'

Full pscheduler.log attached
pscheduler.log

[mfeit-internet2]

This is fixed. Versions of Flask newer than we were using discontinued that parameter.