Py3.6 Scheduled tasks import paths fix, snapshot & scub #2570

[phillxnet]

Fix missing import paths for Py3.6. Follow-up/counter-part to the test-lead pull request #2579 - indicating we have a lack of test coverage here as these failing imports were not uncovered by our tests as the shutdown one was in the referenced pull request.

Affected snapshot & scrub tasks post the Py3.6 transition. Copywrite date and http to https updated on changed files.

Fixes #2570

Testing:

Scheduled Snapshot task

A Web-UI scheduled snapshot (every 5 mins with 2 limit) was created and observed to be instantiated within CRON:

Jun 07 18:25:01 buildvm CRON[25535]: (root) CMD (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:25:02 buildvm CRON[25534]: (root) CMDEND (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:30:01 buildvm CRON[26665]: (root) CMD (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:30:02 buildvm CRON[26663]: (root) CMDEND (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:35:01 buildvm CRON[27625]: (root) CMD (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:35:02 buildvm CRON[27624]: (root) CMDEND (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:40:01 buildvm CRON[29273]: (root) CMD (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)
Jun 07 18:40:03 buildvm CRON[29272]: (root) CMDEND (/opt/rockstor/.venv/bin/st-snapshot 3 \*-*-*-*-*-*)

The resulting Web-UI schedule was updated and expected snapshots were created:

Scheduled Scrub task

A Web-UI scheduled scrub (every 5 mins) and a very small pool was created and seen to be instantiated by CRON:

Jun 07 18:56:01 buildvm cron[875]: (*system*) RELOAD (/etc/cron.d/rockstortab)
...
Jun 07 19:00:01 buildvm CRON[1765]: (root) CMD (/opt/rockstor/.venv/bin/st-pool-scrub 4 \*-*-*-*-*-*)
Jun 07 19:00:02 buildvm kernel: BTRFS info (device vdb): scrub: started on devid 1
Jun 07 19:00:02 buildvm kernel: BTRFS info (device vdb): scrub: finished on devid 1 with status: 0
...
Jun 07 19:01:02 buildvm CRON[1763]: (root) CMDEND (/opt/rockstor/.venv/bin/st-pool-scrub 4 \*-*-*-*-*-*)

And a subsequent scheduled scrub was also observed within the logs:

Jun 07 19:05:01 buildvm CRON[2876]: (root) CMD (/opt/rockstor/.venv/bin/st-pool-scrub 4 \*-*-*-*-*-*)
Jun 07 19:05:02 buildvm kernel: BTRFS info (device vdb): scrub: started on devid 1
Jun 07 19:05:02 buildvm kernel: BTRFS info (device vdb): scrub: finished on devid 1 with status: 0
Jun 07 19:06:02 buildvm CRON[2875]: (root) CMDEND (/opt/rockstor/.venv/bin/st-pool-scrub 4 \*-*-*-*-*-*)

The resulting Web-UI schedule was updated:

and the Pool scrub tab also indicated the scheduled scrubs as expected:

[phillxnet]

@FroggyFlox & @Hooverdan96
Give this pull request is functionally 2 import adjustment to the new Py3.6 base and we have robust testing of the affected function (within pr text) I'll go ahead and merge given our early testing status.

Interesting to see that these import failures were just not uncovered by our tests however. But at least we had the shutdown ones to point us in the rough direction re the required changes here.