From 8f72318fec4f78a4279adc7d766d4da1ab58f516 Mon Sep 17 00:00:00 2001
From: ebarrios <esteban.barrios@trivago.com>
Date: Fri, 5 Mar 2021 16:54:13 +0100
Subject: [PATCH] Added lag column to the kafka plugin

Signed-off-by: ebarrios <esteban.barrios@trivago.com>
---
 .changeset/curvy-poems-cough.md                       |  5 +++++
 .../ConsumerGroupOffsets/ConsumerGroupOffsets.tsx     | 11 +++++++++++
 2 files changed, 16 insertions(+)
 create mode 100644 .changeset/curvy-poems-cough.md

diff --git a/.changeset/curvy-poems-cough.md b/.changeset/curvy-poems-cough.md
new file mode 100644
index 0000000000..6013404490
--- /dev/null
+++ b/.changeset/curvy-poems-cough.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-kafka': patch
+---
+
+Added lag column in the plugin main table
diff --git a/plugins/kafka/src/components/ConsumerGroupOffsets/ConsumerGroupOffsets.tsx b/plugins/kafka/src/components/ConsumerGroupOffsets/ConsumerGroupOffsets.tsx
index 7928393526..3d458194d6 100644
--- a/plugins/kafka/src/components/ConsumerGroupOffsets/ConsumerGroupOffsets.tsx
+++ b/plugins/kafka/src/components/ConsumerGroupOffsets/ConsumerGroupOffsets.tsx
@@ -57,6 +57,17 @@ const generatedColumns: TableColumn[] = [
       return <>{row.groupOffset ?? ''}</>;
     },
   },
+  {
+    title: 'Lag',
+    field: 'lag',
+    render: (row: Partial<TopicPartitionInfo>) => {
+      let lag = undefined;
+      if (row.topicOffset && row.groupOffset) {
+        lag = +topicOffset - +groupOffset;
+      }
+      return <>{lag ?? ''}</>;
+    },
+  },
 ];
 
 type Props = {