Add a batch action to remove all contacts from domains

[CydeWeys]

This implements the first part of Minimum Data Set phase 3, wherein we delete all contact data. This action is necessary to leave a permanent record on the domain (in the form of a domain history entry) documenting when the contacts were removed by the administrative user.

Then, after this has finished removing all contact assocations, we can simply empty out or drop the Contact/ContactHistory tables and associated join tables.

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This change is 

[jicelhay]

@jicelhay reviewed 1 of 4 files at r1, all commit messages.
Reviewable status: 1 of 7 files reviewed, 1 unresolved discussion

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core/src/main/java/google/registry/batch/RemoveAllDomainContactsAction.java line 195 at r7 (raw file):

    for (DesignatedContact designatedContact : domain.getContacts()) {
      @Nullable Contact contact = contacts.get(designatedContact.getContactKey());
      if (contact == null) {

is there any AI for domains that have this data?

[CydeWeys]

Reviewable status: 1 of 7 files reviewed, 1 unresolved discussion (waiting on @jicelhay)

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core/src/main/java/google/registry/batch/RemoveAllDomainContactsAction.java line 195 at r7 (raw file):

Previously, jicelhay (Juan Celhay) wrote…

is there any AI for domains that have this data?

This is a state in the system that shouldn't exist -- indeed foreign keys at the DB schema layer should probably ensure that it doesn't. And if it does exist, then it's not fixable via EPP, as the domain update flow would run into the same problem.

So I think the best we can do here is, in the unlikely event of this scenario, log it, and then go in and fix it manually. I suspect we won't have any occurrences of this, though. (But if I didn't explicitly handle the situation, then sb.append(...) below could run into an NPE.

[jicelhay]

@jicelhay reviewed 1 of 4 files at r1, 1 of 3 files at r4, 4 of 4 files at r7.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @CydeWeys)