From cf209db6b91a6638a9b32b7e9393b84ef27caaad Mon Sep 17 00:00:00 2001
From: Girish Kumar <45126881+0xgirish@users.noreply.github.com>
Date: Sat, 27 Apr 2024 02:55:57 +0530
Subject: [PATCH 1/2] fix: client.Lag doesn't calculate lag for all
 consumergroups with client.Lag(ctx)

Signed-off-by: Girish Kumar <45126881+0xgirish@users.noreply.github.com>
---
 pkg/kadm/groups.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pkg/kadm/groups.go b/pkg/kadm/groups.go
index 6adca804..477a9b63 100644
--- a/pkg/kadm/groups.go
+++ b/pkg/kadm/groups.go
@@ -1460,7 +1460,12 @@ func (cl *Client) Lag(ctx context.Context, groups ...string) (DescribedGroupLags
 		}
 		if g.Err != nil {
 			delete(set, g.Group)
+			continue
 		}
+
+		// if no groups were specified for lag calculation, we will calculate lag for all groups
+		// adding groups to the set again.
+		set[g.Group] = struct{}{}
 	}
 	if len(set) == 0 {
 		return lags, nil

From 823ff5bf1b40e0b1662ccc93e4fdbf7617cb5492 Mon Sep 17 00:00:00 2001
From: Girish Kumar <45126881+0xgirish@users.noreply.github.com>
Date: Sat, 4 May 2024 10:36:22 +0530
Subject: [PATCH 2/2] Update groups.go

---
 pkg/kadm/groups.go | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/pkg/kadm/groups.go b/pkg/kadm/groups.go
index 477a9b63..2716450f 100644
--- a/pkg/kadm/groups.go
+++ b/pkg/kadm/groups.go
@@ -1463,8 +1463,9 @@ func (cl *Client) Lag(ctx context.Context, groups ...string) (DescribedGroupLags
 			continue
 		}
 
-		// if no groups were specified for lag calculation, we will calculate lag for all groups
-		// adding groups to the set again.
+		// If the input set of groups is empty, DescribeGroups returns all groups.
+		// We add to `set` here so that the Lag function itself can calculate
+		// lag for all groups.
 		set[g.Group] = struct{}{}
 	}
 	if len(set) == 0 {