From 067aefd6a2e189ec35b943b7e8d04176d194af35 Mon Sep 17 00:00:00 2001
From: Jun Nemoto <35618893+jnmt@users.noreply.github.com>
Date: Mon, 4 Aug 2025 13:12:48 +0900
Subject: [PATCH] Disable the coordinator write omission in ScalarDB (#203)

---
 .../scalar/dl/ledger/config/LedgerConfig.java |  8 +++++
 .../dl/ledger/config/LedgerConfigTest.java    | 34 +++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/ledger/src/main/java/com/scalar/dl/ledger/config/LedgerConfig.java b/ledger/src/main/java/com/scalar/dl/ledger/config/LedgerConfig.java
index a139f300..9c6eede0 100644
--- a/ledger/src/main/java/com/scalar/dl/ledger/config/LedgerConfig.java
+++ b/ledger/src/main/java/com/scalar/dl/ledger/config/LedgerConfig.java
@@ -519,6 +519,14 @@ private void validateTransactionManager() {
             LedgerError.CONFIG_GROUP_COMMIT_MUST_BE_DISABLED.buildMessage(
                 ConsensusCommitConfig.COORDINATOR_GROUP_COMMIT_ENABLED));
       }
+      if (consensusCommitConfig.isCoordinatorWriteOmissionOnReadOnlyEnabled()) {
+        LOGGER.warn(
+            "Disabling the unsupported option '{}' because Coordinator writes are always necessary for ScalarDL",
+            ConsensusCommitConfig.COORDINATOR_WRITE_OMISSION_ON_READ_ONLY_ENABLED);
+        props.setProperty(
+            ConsensusCommitConfig.COORDINATOR_WRITE_OMISSION_ON_READ_ONLY_ENABLED,
+            Boolean.toString(false));
+      }
     }
   }
 
diff --git a/ledger/src/test/java/com/scalar/dl/ledger/config/LedgerConfigTest.java b/ledger/src/test/java/com/scalar/dl/ledger/config/LedgerConfigTest.java
index f10df9c1..86a93bff 100644
--- a/ledger/src/test/java/com/scalar/dl/ledger/config/LedgerConfigTest.java
+++ b/ledger/src/test/java/com/scalar/dl/ledger/config/LedgerConfigTest.java
@@ -581,4 +581,38 @@ public void constructor_HmacEnabledButCipherKeyNotGiven_ShouldThrowIllegalArgume
     // Assert
     assertThat(thrown).isExactlyInstanceOf(IllegalArgumentException.class);
   }
+
+  @Test
+  public void
+      constructor_ConsensusCommitWithCoordinatorWriteOmissionDisabledSpecified_ShouldConstructProperly() {
+    // Arrange
+    props.setProperty(DatabaseConfig.TRANSACTION_MANAGER, "consensus-commit");
+    props.setProperty(
+        ConsensusCommitConfig.COORDINATOR_WRITE_OMISSION_ON_READ_ONLY_ENABLED, "false");
+
+    // Act
+    LedgerConfig config = new LedgerConfig(props);
+    ConsensusCommitConfig consensusCommitConfig =
+        new ConsensusCommitConfig(config.getDatabaseConfig());
+
+    // Assert
+    assertThat(consensusCommitConfig.isCoordinatorWriteOmissionOnReadOnlyEnabled()).isFalse();
+  }
+
+  @Test
+  public void
+      constructor_ConsensusCommitWithCoordinatorWriteOmissionEnabledSpecified_ShouldConstructProperlyWithDisablingIt() {
+    // Arrange
+    props.setProperty(DatabaseConfig.TRANSACTION_MANAGER, "consensus-commit");
+    props.setProperty(
+        ConsensusCommitConfig.COORDINATOR_WRITE_OMISSION_ON_READ_ONLY_ENABLED, "true");
+
+    // Act
+    LedgerConfig config = new LedgerConfig(props);
+    ConsensusCommitConfig consensusCommitConfig =
+        new ConsensusCommitConfig(config.getDatabaseConfig());
+
+    // Assert
+    assertThat(consensusCommitConfig.isCoordinatorWriteOmissionOnReadOnlyEnabled()).isFalse();
+  }
 }