From af401a0d71f6400bf1676ba9110765f2ee8b0e84 Mon Sep 17 00:00:00 2001
From: Jiri Pechanec <jpechane@redhat.com>
Date: Mon, 6 Dec 2021 06:51:39 +0100
Subject: [PATCH] DBZ-4205 Handle new transaction id format

---
 .../mongodb/MongoDbEventMetadataProvider.java      | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/debezium-connector-mongodb/src/main/java/io/debezium/connector/mongodb/MongoDbEventMetadataProvider.java b/debezium-connector-mongodb/src/main/java/io/debezium/connector/mongodb/MongoDbEventMetadataProvider.java
index 52b114ae9..5375b417e 100644
--- a/debezium-connector-mongodb/src/main/java/io/debezium/connector/mongodb/MongoDbEventMetadataProvider.java
+++ b/debezium-connector-mongodb/src/main/java/io/debezium/connector/mongodb/MongoDbEventMetadataProvider.java
@@ -69,6 +69,20 @@ public String getTransactionId(DataCollectionId source, OffsetContext offset, Ob
                 return sessionTxnId;
             }
         }
+        // Both components were always present in the testing but the documentation claims they are optional
+        // so it is better to code this defensively
+        if (sourceInfo.schema().field(SourceInfo.LSID) != null && (sourceInfo.getString(SourceInfo.LSID) != null
+                || sourceInfo.getInt64(SourceInfo.TXN_NUMBER) != null)) {
+            final String lsid = sourceInfo.getString(SourceInfo.LSID);
+            final Long txnNumber = sourceInfo.getInt64(SourceInfo.TXN_NUMBER);
+            if (lsid == null) {
+                return txnNumber.toString();
+            }
+            if (txnNumber == null) {
+                return lsid;
+            }
+            return lsid + ":" + txnNumber;
+        }
         final Long operationId = sourceInfo.getInt64(SourceInfo.OPERATION_ID);
         if (operationId == null) {
             return null;