When scheduling a cron interval, the first run is not the at the expected time

[erikthegamer1242]

Describe the bug

I want WatchTower to update every Friday at 6AM and when starting it says

Scheduling first run: 2022-05-01 00:06:00 +0000 UTC
Note that the first check will be performed in 1346 hours, 55 minutes, 22 seconds

To Reproduce

Steps to reproduce the behavior:

1. Start container with docker run env variable '-e WATCHTOWER_SCHEDULE="0 6 * * 5"'
2. Look at docker logs and receive:
   Scheduling first run: 2022-05-01 00:06:00 +0000 UTC Note that the first check will be performed in 1346 hours, 55 minutes, 22 seconds

Expected behavior

It should start at next Friday at 6AM
Screenshots

Environment

• Platform: Linux docker-vm 5.4.0-100-generic 113-Ubuntu SMP Thu Feb 3 18:43:29 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
• Architecture linux/amd64
• Docker version Docker version 20.10.12, build e91ed57

Logs from running watchtower with the --debug option

Additional context

[piksel]

The schedule should be represented by 6 fields, not 5:
https://containrrr.dev/watchtower/arguments/#scheduling

This is due to the scheduler library being used. They changed to the 5-field version in later version, but it would be a breaking change to upgrade to it.

[erikthegamer1242]

Thanks a lot, works!

[ewoks]

follow up question in that context @piksel :
is first run here mandatory delayed? Is there a way to execute check soon after start and after that according to schedule?