Add a dry-run option to commit-log-replay action and use it in Sandbox (#1234)

core/src/test/java/google/registry/backup/ReplayCommitLogsToSqlActionTest.java

@@ -208,6 +208,30 @@ public class ReplayCommitLogsToSqlActionTest {
     assertExpectedIds("previous to keep");
   }
 
+  @Test
+  void testReplay_dryRun() throws Exception {
+    action.dryRun = true;
+    DateTime now = fakeClock.nowUtc();
+    jpaTm().transact(() -> jpaTm().insertWithoutBackup(TestObject.create("previous to keep")));
+    Key<CommitLogBucket> bucketKey = getBucketKey(1);
+    Key<CommitLogManifest> manifestKey = CommitLogManifest.createKey(bucketKey, now);
+    saveDiffFileNotToRestore(gcsService, now.minusMinutes(2));
+    jpaTm().transact(() -> SqlReplayCheckpoint.set(now.minusMinutes(1).minusMillis(1)));
+    saveDiffFile(
+        gcsService,
+        createCheckpoint(now.minusMinutes(1)),
+        CommitLogManifest.create(bucketKey, now, null),
+        CommitLogMutation.create(manifestKey, TestObject.create("a")),
+        CommitLogMutation.create(manifestKey, TestObject.create("b")));
+
+    action.run();
+    assertThat(response.getStatus()).isEqualTo(SC_OK);
+    assertThat(response.getPayload())
+        .isEqualTo(
+            "Running in dry-run mode; would have processed %d files. They are (limit 10):\n"
+                + "commit_diff_until_1999-12-31T23:59:00.000Z");
+  }
+
   @Test
   void testReplay_manifestWithNoDeletions() throws Exception {
     DateTime now = fakeClock.nowUtc();