[proposal] PodMigrationJob support external conditions

[sjtufl]

What is your proposal: Introduce mechanism for PodMigrationJob to make sure that some external conditions are met before performing actual evictions on pods.

Why is this needed: PodMigrationJob supports two types of pod migration modes currently, i.e. EvictDirectly and ReservationFirst. Pod eviction is performed directly, or after Reservation is successfully scheduled. However, as an operation at high risk, evicting pod must meet some external interception conditions in scenarios with high technical risk requirements (such as financial scenarios). Typical external conditions include cutting off North/South & East/West traffic, getting approval from change risk control system, etc. Therefore, the external conditions mechanism is needed to let the PodMigrationJob check whether the predefined interception conditions have been met before performing the actual eviction operation, reducing the risk of pod migration.

Is there a suggested solution, if so, please add it:

[sjtufl]

/assign

[eahydra]

Awesome! Looking forward to Proposals and PRs. 🎉

[ZiMengSheng]

/milestone 1.4

[koordinator-bot[bot]]

@ZiMengSheng: You must be a member of the koordinator-sh/milestone-maintainers GitHub team to set the milestone. If you believe you should be able to issue the /milestone command, please contact your and have them propose you as an additional delegate for this responsibility.

In response to this:

/milestone 1.4

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. This bot triages issues and PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, the issue is closed You can:
• Mark this issue or PR as fresh with /remove-lifecycle stale
• Close this issue or PR with /close Thank you for your contributions.

[stale[bot]]

This issue has been automatically closed because it has not had recent activity. This bot triages issues and PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, the issue is closed You can:
• Reopen this PR with /reopen Thank you for your contributions.