Configure

1. Write the config file

$ bakasync init
config  ~/.config/bakasync/config.env  (created)
key     ~/.config/bakasync/service-account.json  (missing)

Download the service account key from GCP and save it
to the path above, then run: bakasync doctor

2. Put the key where it says

$ mv ~/Downloads/project-a1b2c3.json ~/.config/bakasync/service-account.json
$ chmod 600 ~/.config/bakasync/service-account.json

3. Fill in three values

BAKASYNC_BASE_URL=https://bakalari.example.cz/bakaweb
BAKASYNC_CLASS_ID=1A
BAKASYNC_CALENDAR_ID=abc123@group.calendar.google.com

BAKASYNC_CLASS_ID is the id in the timetable URL, not the class name. Open the public timetable in a browser and read it off the address bar.

Add BAKASYNC_GROUPS if your class splits, and BAKASYNC_EXPECTED_CLASS_NAME to be told when the page stops being your class. Everything else has a default: see Variables.

4. Check

$ bakasync doctor
config    ~/.config/bakasync/config.env
key       ok, sync@project.iam.gserviceaccount.com
timetable ok, class "1.A", 43 lessons
calendar  FAILED: google api returned 404 Not Found: ...
          the calendar id is wrong, or it is not shared with the service account

A clean run ends with all good, run bakasync --plan to see what the next sync would change.