Parse the last partial line in CRI logs

[mrunalp]

@Random-Liu @yujuhong @runcom @feiskyer PTAL

Fixes part of #44976

This should work while we find a longer term format for CRI logs.

Signed-off-by: Mrunal Patel [email protected]

What this PR does / why we need it:
This PR attempts to parse the last line of log even if it doesn't have a newline. Today for CRI based log formats such lines are ignored and empty output is returned.

Which issue(s) this PR fixes
Fixes part of #44976

Special notes for your reviewer:
Use a CRI runtime like CRI-O and the output will be empty for these commands without this PR.

# kubectl create -f https://raw.githubusercontent.com/openshift-qe/v3-testfiles/master/configmap/configmap.yaml
# kubectl create -f https://raw.githubusercontent.com/openshift-qe/v3-testfiles/master/configmap/pod-configmap-volume1.yaml 
# kubectl logs dapi-test-pod-1 
very# 

Release Note:

NONE

[derekwaynecarr]

@mrunalp - this implements what was proposed here in the absence of a better solution?

#44976 (comment)

what you have now is better than what we have previously, so this works for me for the moment.

[mrunalp]

@derekwaynecarr Yes, that's what this PR implements.
This can be improved later when we modify the log format but is the best we can do for now.

[derekwaynecarr]

this is no worse than what we have before, and makes more content visible to users that were previously invisible. in that vein, this is good to me and doesn't preclude us doing more in future.

/approve
/lgtm

[k8s-github-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: derekwaynecarr, mrunalp

Associated issue: 44976

The full list of commands accepted by this bot can be found here.

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• pkg/kubelet/OWNERS [derekwaynecarr]

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[Random-Liu]

LGTM. I prefer adding a helper function instead of copying code, but I'm fine with doing that in another PR.

[feiskyer]

LGTM. We may also add a test for such case.

[k8s-github-robot]

Automatic merge from submit-queue (batch tested with PRs 55697, 55631, 51905, 55647, 55826). If you want to cherry-pick this change to another branch, please follow the instructions here.