Add the DNS refresh request time field to the Domain tables (#1279)

* Add the DNS refresh request time field to the Domain tables

This isn't used yet, but it will eventually be the replacement for the dns-pull
task queue once we get further in the migration.

* Merge branch 'master' into domain-dns-dirty

core/src/main/java/google/registry/model/domain/DomainBase.java

@@ -65,7 +65,8 @@ import org.joda.time.DateTime;
       @Index(columnList = "domainName"),
       @Index(columnList = "techContact"),
       @Index(columnList = "tld"),
-      @Index(columnList = "registrantContact")
+      @Index(columnList = "registrantContact"),
+      @Index(columnList = "dnsRefreshRequestTime")
     })
 @WithStringVKey
 @ExternalMessagingName("domain")
@@ -213,7 +214,8 @@ public class DomainBase extends DomainContent
           .setSmdId(domainContent.getSmdId())
           .setSubordinateHosts(domainContent.getSubordinateHosts())
           .setStatusValues(domainContent.getStatusValues())
-          .setTransferData(domainContent.getTransferData());
+          .setTransferData(domainContent.getTransferData())
+          .setDnsRefreshRequestTime(domainContent.getDnsRefreshRequestTime());
     }
   }
 }

core/src/main/java/google/registry/model/domain/DomainContent.java

@@ -50,6 +50,7 @@ import com.googlecode.objectify.annotation.IgnoreSave;
 import com.googlecode.objectify.annotation.Index;
 import com.googlecode.objectify.annotation.OnLoad;
 import com.googlecode.objectify.condition.IfNull;
+import google.registry.dns.RefreshDnsAction;
 import google.registry.flows.ResourceFlowUtils;
 import google.registry.model.EppResource;
 import google.registry.model.EppResource.ResourceWithTransferData;
@@ -303,6 +304,35 @@ public class DomainContent extends EppResource
    */
   @Index DateTime autorenewEndTime;
 
+  /**
+   * When this domain's DNS was requested to be refreshed, or null if its DNS is up-to-date.
+   *
+   * <p>This will almost always be null except in the couple minutes' interval between when a
+   * DNS-affecting create or update operation takes place and when the {@link RefreshDnsAction}
+   * runs, which resets this back to null upon completion of the DNS refresh task. This is a {@link
+   * DateTime} rather than a simple dirty boolean so that the DNS refresh action can order by the
+   * DNS refresh request time and take action on the oldest ones first.
+   *
+   * <p>Note that this is a Cloud SQL-based replacement for the {@code dns-pull} task queue. The
+   * domains that have a non-null value for this field should be exactly the same as the tasks that
+   * would be in the {@code dns-pull} queue. Because this is Cloud SQL-specific, it is omitted from
+   * Datastore.
+   *
+   * <p>Note that in the {@link DomainHistory} table this value means something slightly different:
+   * It means that the given domain action requested a DNS update. Unlike on the {@code Domain}
+   * table, this value is not then subsequently nulled out once the DNS refresh is complete; rather,
+   * it remains as a permanent record of which actions were DNS-affecting and which were not.
+   */
+  // TODO(mcilwain): Start using this field once we are further along in the DB migration.
+  @Ignore DateTime dnsRefreshRequestTime;
+
+  /**
+   * Returns the DNS refresh request time iff this domain's DNS needs refreshing, otherwise absent.
+   */
+  public Optional<DateTime> getDnsRefreshRequestTime() {
+    return Optional.ofNullable(dnsRefreshRequestTime);
+  }
+
   @OnLoad
   void load() {
     // Reconstitute all of the contacts so that they have VKeys.
@@ -967,6 +997,11 @@ public class DomainContent extends EppResource
       return thisCastToDerived();
     }
 
+    public B setDnsRefreshRequestTime(Optional<DateTime> dnsRefreshRequestTime) {
+      getInstance().dnsRefreshRequestTime = dnsRefreshRequestTime.orElse(null);
+      return thisCastToDerived();
+    }
+
     public B setSmdId(String smdId) {
       getInstance().smdId = smdId;
       return thisCastToDerived();

core/src/test/java/google/registry/model/domain/DomainBaseTest.java

@@ -173,6 +173,7 @@ public class DomainBaseTest extends EntityTestCase {
                             "registrar",
                             null))
                     .setAutorenewEndTime(Optional.of(fakeClock.nowUtc().plusYears(2)))
+                    .setDnsRefreshRequestTime(Optional.of(fakeClock.nowUtc()))
                     .build()));
   }
 

core/src/test/java/google/registry/model/history/DomainHistoryTest.java

@@ -53,6 +53,8 @@ import google.registry.testing.DatabaseHelper;
 import google.registry.testing.DualDatabaseTest;
 import google.registry.testing.TestOfyOnly;
 import google.registry.testing.TestSqlOnly;
+import java.util.Optional;
+import org.joda.time.DateTime;
 import org.junit.jupiter.api.BeforeEach;
 
 /** Tests for {@link DomainHistory}. */
@@ -245,6 +247,7 @@ public class DomainHistoryTest extends EntityTestCase {
             .asBuilder()
             .setNameservers(host.createVKey())
             .setDsData(ImmutableSet.of(DelegationSignerData.create(1, 2, 3, new byte[] {0, 1, 2})))
+            .setDnsRefreshRequestTime(Optional.of(DateTime.parse("2020-03-09T16:40:00Z")))
             .build();
     jpaTm().transact(() -> jpaTm().insert(domain));
     return domain;