fix(3235): Fetch parentEvent meta when create Event

[kumada626]

Context

When restart build was failed in sd-setup-init step and restart build from that build, meta is missing at that time.
So we fix this behavior by fetching parent event meta when creating event.

Objective

Fetch parent event meta when creating event.

References

#3225

License

I confirm that this contribution is made under a BSD license and that I have the authority necessary to make this contribution on behalf of its copyright owner.

[coveralls]

coverage: 95.329% (+0.008%) from 95.321%
when pulling 065df39 on fetch-parent-meta
into 7c71738 on master.

[VonnyJap]

what about make this more simplified?

Suggested change

	let mergedParameters = {};
	payload.baseBranch = parentEvent.baseBranch || null;
	if (!payload.meta.parameters && parentEvent.meta && parentEvent.meta.parameters) {
	payload.meta.parameters = parentEvent.meta.parameters;
	mergedParameters = parentEvent.meta.parameters;
	}
	if (Object.keys(payload.meta).length === 0) {
	payload.meta = { ...parentEvent.meta };
	}
	if (Object.keys(mergedParameters).length > 0) {
	payload.meta.parameters = mergedParameters;
	}
	// Merge parameters if they exist in the parent event and not in the payload
	if (!payload.meta.parameters && parentEvent.meta && parentEvent.meta.parameters) {
	payload.meta.parameters = parentEvent.meta.parameters;
	}
	// Copy meta from parent event if payload.meta is empty
	if (Object.keys(payload.meta).length === 0) {
	payload.meta = { ...parentEvent.meta };
	}

[kumada626]

If payload(RestartedEevnt) only has parameters in meta, I think your suggested method will not fetch parentEvent meta (and neither will my method).
I will have fixed this bug.

[VonnyJap]

please check my suggestion

[VonnyJap]

@kumada626 - can you also add couple of functional tests
https://github.com/screwdriver-cd/screwdriver/blob/master/features/metadata.feature
Changes to metadata behavior can be crucial and we should add some functional tests to make sure that it is working as intended if possible.

[kumada626]

@VonnyJap Since this change does not alter normal behavior, it would be difficult to add it as a functional test.
This change is to fix the case of a restart from a build that failed in setup-init of a build due to some temporary environmental factors, so if we can guarantee that the normal behavior has not changed, there should be no problem.