feat: Add immediate option to ReplicationSource

[onedr0p]

Describe what this PR does

Adds immediate option to ReplicationSource - immediate can be used to stop replication when a new ReplicationSource is created. Defaults to "true".

Is there anything that requires special attention?

I am unable to run make test (Apple Silicon issue?) locally so looking for some feedback. This also could use some unit tests if required, however I am unable to write & test due to that issue until I find another way.

Related issues:
#627

[openshift-ci]

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[openshift-ci]

Hi @onedr0p. Thanks for your PR.

I'm waiting for a backube member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[codecov]

Codecov Report

Merging #812 (f74f1f5) into main (49fe3ef) will decrease coverage by 0.1%.
The diff coverage is 63.6%.

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #812     +/-   ##
=======================================
- Coverage   66.9%   66.9%   -0.1%     
=======================================
  Files         55      55             
  Lines       7058    7091     +33     
=======================================
+ Hits        4726    4747     +21     
- Misses      2054    2062      +8     
- Partials     278     282      +4     

Files Changed	Coverage Δ
controllers/mover/syncthing/mover.go	81.2% <ø> (ø)
controllers/mover/rclone/builder.go	87.8% <40.0%> (-2.2%)	⬇️
controllers/mover/restic/builder.go	88.8% <40.0%> (-2.1%)	⬇️
controllers/mover/rsync/builder.go	89.0% <40.0%> (-2.0%)	⬇️
controllers/mover/rsynctls/builder.go	89.3% <40.0%> (-2.0%)	⬇️
controllers/mover/rclone/mover.go	71.8% <100.0%> (+0.3%)	⬆️
controllers/mover/restic/mover.go	81.6% <100.0%> (+0.1%)	⬆️
controllers/mover/rsync/mover.go	76.7% <100.0%> (+0.2%)	⬆️
controllers/mover/rsynctls/mover.go	71.1% <100.0%> (+0.2%)	⬆️
controllers/mover/syncthing/builder.go	92.9% <100.0%> (+0.1%)	⬆️

[sonarcloud]

SonarCloud Quality Gate failed.   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
13.8% Duplication

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[tesshuflower]

@onedr0p thanks for this PR, however I think if we do this there are a few updates we'd need to do:

• If we add immediate to replicationsource I'd prefer to also add to replicationdestination to be consistent
• Does it make sense to add immediate to spec.trigger somewhere? And potentially even call this something like spec.trigger.scheduleImmediate? Since I think this will not apply (and should be ignored) by manual triggers.
• I think the actual implementation will need to be modified to set status/modify the scheduling algorithm to make sure we skip this initial sync if immediate is false. The way it's done in the PR prevents the job from starting - which would be the same effect as creating a replicationsource with paused=true. The problem with this is everything else will still happen immediately - i.e. snapshot/clone will be taken of the pvc immediately, and that pvc from snap/clone will be of the PVC at the time when the replicationsource is created. I think to do this as you intend, we'd need to modify the scheduling to not sync at all at the start which is a little more involved as we don't want to risk breaking the scheduling.

I'll discuss with the rest of the team to see if this does sound like a valid direction to go - I will try to take a look at the scheduling when I have a moment and see if it's something that could be done relatively easily.

[onedr0p]

Closing PR, will circle back if needed after the volume populator functionality is released. I still think this might be needed for other situations but there's problems with this PR as pointed out above.