Config options fix

[shmuelk]

What type of PR is this?
/kind bug

What this PR does / why we need it:
A textual configuration is required by the EPP to run.

If neither the config-text nor the config-file options are specified, the EPP crashes with a nil pointer error.

This PR adds to the options validation code a check that one of the config-text or config-file command line arguments has been specified.

In addition this PR adds a very simple log setup for the initial log messages issued before the command line arguments parse and validate correctly. Without this, no error messages show up in the EPP's stdout. See https://pkg.go.dev/sigs.k8s.io/controller-runtime/pkg/log#hdr-The_Log_Handle for more details.

Which issue(s) this PR fixes:
Fixes #2297

Does this PR introduce a user-facing change?:

NONE

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[elevran]

Q: is it (or should it be) possible to run EPP without a configuration file? There are runner options that set config directly in code (With...()). Sould the validation also check the configuration pointers on the runner?

[ahg-g]

Ideally we should have a default configuration. I think in general our config defaulting, especially the way individual plugins config defaulting is done needs re-work.

[nirrozenbaum]

practically atm we provide default plugins for certain extension points.
we don't provide default configuration if non was specified.
as an immediate fix for the segfault this looks good from my side.
longer term I agree default configuration would be a nicer solution.

[shmuelk]

The current With...() functions of the runner do not set enough configuration related stuff.

When the datalayer goes production, there will be more work done.

[nirrozenbaum]

/lgtm
/approve

holding in case @elevran or @ahg-g have more comments.
if not please unhold.
/hold

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: nirrozenbaum, shmuelk

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• OWNERS [nirrozenbaum]

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[ahg-g]

/lgtm

[ahg-g]

/hold cancel

[shmuelk]

I have created issue #2324 to discuss and track the adding of a default configuration for the EPP.

[kfswain]

/cherrypick release-1.3

[k8s-infra-cherrypick-robot]

@kfswain: #2321 failed to apply on top of branch "release-1.3":

Applying: Added check that one of confi-text or config-file is specified
Applying: Added dummy config-file argument to get tests to pass
Applying: Add a very basic logger to log startup messages in case of errors
Using index info to reconstruct a base tree...
M	cmd/epp/runner/runner.go
A	pkg/common/observability/logging/logger.go
Falling back to patching base and 3-way merge...
Auto-merging pkg/epp/util/logging/logger.go
CONFLICT (content): Merge conflict in pkg/epp/util/logging/logger.go
Auto-merging cmd/epp/runner/runner.go
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"
Patch failed at 0003 Add a very basic logger to log startup messages in case of errors

Details

In response to this:

/cherrypick release-1.3

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