From d9739e02e0e32539736e426ae7e642c580cb6b22 Mon Sep 17 00:00:00 2001
From: Daniel del Castillo <dadelcas@hotmail.com>
Date: Tue, 13 Mar 2018 11:47:08 +0000
Subject: [PATCH] [issue-47] Better replica-check exception message

---
 CHANGELOG.md                                         |  4 ++++
 .../core/replica/DestinationNotReplicaException.java | 12 +++++++++---
 .../hotels/bdp/circustrain/core/replica/Replica.java |  5 +++--
 3 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 700468ed..441500da 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# TBD
+### Changed
+* Clearer replica-check exception message. See [#47](https://github.com/HotelsDotCom/circus-train/issues/47).
+
 # 11.3.0 - 2018-02-27
 ### Changed
 * SNS message now indicates if message was truncated. See [#41](https://github.com/HotelsDotCom/circus-train/issues/41).
diff --git a/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/DestinationNotReplicaException.java b/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/DestinationNotReplicaException.java
index dc6fcf90..e7a382be 100644
--- a/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/DestinationNotReplicaException.java
+++ b/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/DestinationNotReplicaException.java
@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2016-2017 Expedia Inc.
+ * Copyright (C) 2016-2018 Expedia Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,17 +19,23 @@
 import org.apache.hadoop.hive.metastore.api.Table;
 
 import com.hotels.bdp.circustrain.api.CircusTrainException;
+import com.hotels.bdp.circustrain.api.CircusTrainTableParameter;
 
 public class DestinationNotReplicaException extends CircusTrainException {
 
   private static final long serialVersionUID = 1L;
 
-  DestinationNotReplicaException(Table oldReplicaTable, String replicaMetastoreUris) {
+  DestinationNotReplicaException(
+      Table oldReplicaTable,
+      String replicaMetastoreUris,
+      CircusTrainTableParameter tableParameter) {
     super("Found an existing table '"
         + Warehouse.getQualifiedName(oldReplicaTable)
         + "' in '"
         + replicaMetastoreUris
-        + "', but it does not appear to be a replica!");
+        + "', but it does not appear to be a replica! Missing table property '"
+        + tableParameter.parameterName()
+        + "'");
   }
 
 }
diff --git a/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/Replica.java b/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/Replica.java
index 1ab78f50..98375f9c 100644
--- a/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/Replica.java
+++ b/circus-train-core/src/main/java/com/hotels/bdp/circustrain/core/replica/Replica.java
@@ -50,6 +50,7 @@
 import com.hotels.bdp.circustrain.api.ReplicaLocationManager;
 import com.hotels.bdp.circustrain.api.SourceLocationManager;
 import com.hotels.bdp.circustrain.api.event.ReplicaCatalogListener;
+import com.hotels.bdp.circustrain.api.listener.HousekeepingListener;
 import com.hotels.bdp.circustrain.api.metastore.CloseableMetaStoreClient;
 import com.hotels.bdp.circustrain.api.metastore.MetaStoreClientException;
 import com.hotels.bdp.circustrain.core.HiveEndpoint;
@@ -60,7 +61,6 @@
 import com.hotels.bdp.circustrain.core.conf.TableReplication;
 import com.hotels.bdp.circustrain.core.event.EventUtils;
 import com.hotels.bdp.circustrain.core.metastore.LocationUtils;
-import com.hotels.bdp.circustrain.api.listener.HousekeepingListener;
 
 public class Replica extends HiveEndpoint {
 
@@ -297,7 +297,8 @@ private void determinValidityOfReplica(ReplicationMode replicationMode, Table ol
     // REPLICATION_EVENT to determine if a table was created via CT.
     String previousEvent = oldReplicaTable.getParameters().get(REPLICATION_EVENT.parameterName());
     if (StringUtils.isBlank(previousEvent)) {
-      throw new DestinationNotReplicaException(oldReplicaTable, getHiveConf().getVar(ConfVars.METASTOREURIS));
+      throw new DestinationNotReplicaException(oldReplicaTable, getHiveConf().getVar(ConfVars.METASTOREURIS),
+          REPLICATION_EVENT);
     }
     LOG.debug("Checking that replication modes are compatible.");
     Optional<ReplicationMode> replicaReplicationMode = Enums.getIfPresent(ReplicationMode.class,