From ce981d15443fe1348e3b5cc5e12da71c45e1a16c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Johannes=20Br=C3=BCderl?= <johannes.bruederl@gmail.com>
Date: Tue, 2 Jul 2019 15:45:00 +0200
Subject: [PATCH] admin: add DeleteConsumerGroup

---
 admin.go         | 32 +++++++++++++++++++++++++++++++-
 admin_test.go    | 30 ++++++++++++++++++++++++++++++
 mockresponses.go | 23 +++++++++++++++++++++++
 3 files changed, 84 insertions(+), 1 deletion(-)

diff --git a/admin.go b/admin.go
index d88a0a493..18ca4918d 100644
--- a/admin.go
+++ b/admin.go
@@ -84,7 +84,10 @@ type ClusterAdmin interface {
 	// List the consumer group offsets available in the cluster.
 	ListConsumerGroupOffsets(group string, topicPartitions map[string][]int32) (*OffsetFetchResponse, error)
 
-	// Get information about the nodes in the cluster.
+	// Delete a consumer group.
+	DeleteConsumerGroup(group string) error
+
+	// Get information about the nodes in the cluster
 	DescribeCluster() (brokers []*Broker, controllerID int32, err error)
 
 	// Close shuts down the admin and closes underlying client.
@@ -614,3 +617,30 @@ func (ca *clusterAdmin) ListConsumerGroupOffsets(group string, topicPartitions m
 
 	return coordinator.FetchOffset(request)
 }
+
+func (ca *clusterAdmin) DeleteConsumerGroup(group string) error {
+	coordinator, err := ca.client.Coordinator(group)
+	if err != nil {
+		return err
+	}
+
+	request := &DeleteGroupsRequest{
+		Groups: []string{group},
+	}
+
+	resp, err := coordinator.DeleteGroups(request)
+	if err != nil {
+		return err
+	}
+
+	groupErr, ok := resp.GroupErrorCodes[group]
+	if !ok {
+		return ErrIncompleteResponse
+	}
+
+	if groupErr != ErrNoError {
+		return groupErr
+	}
+
+	return nil
+}
diff --git a/admin_test.go b/admin_test.go
index aafb1481a..40061113b 100644
--- a/admin_test.go
+++ b/admin_test.go
@@ -859,3 +859,33 @@ func TestListConsumerGroupOffsets(t *testing.T) {
 	}
 
 }
+
+func TestDeleteConsumerGroup(t *testing.T) {
+	seedBroker := NewMockBroker(t, 1)
+	defer seedBroker.Close()
+
+	group := "my-group"
+
+	seedBroker.SetHandlerByMap(map[string]MockResponse{
+		// "OffsetFetchRequest":  NewMockOffsetFetchResponse(t).SetOffset(group, "my-topic", partition, expectedOffset, "", ErrNoError),
+		"DeleteGroupsRequest": NewMockDeleteGroupsRequest(t).SetDeletedGroups([]string{group}),
+		"MetadataRequest": NewMockMetadataResponse(t).
+			SetController(seedBroker.BrokerID()).
+			SetBroker(seedBroker.Addr(), seedBroker.BrokerID()),
+		"FindCoordinatorRequest": NewMockFindCoordinatorResponse(t).SetCoordinator(CoordinatorGroup, group, seedBroker),
+	})
+
+	config := NewConfig()
+	config.Version = V1_1_0_0
+
+	admin, err := NewClusterAdmin([]string{seedBroker.Addr()}, config)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = admin.DeleteConsumerGroup(group)
+	if err != nil {
+		t.Fatalf("DeleteConsumerGroup failed with error %v", err)
+	}
+
+}
diff --git a/mockresponses.go b/mockresponses.go
index 919d8bb07..3b0747c1f 100644
--- a/mockresponses.go
+++ b/mockresponses.go
@@ -885,3 +885,26 @@ func (mr *MockDeleteAclsResponse) For(reqBody versionedDecoder) encoder {
 	}
 	return res
 }
+
+type MockDeleteGroupsResponse struct {
+	deletedGroups []string
+}
+
+func NewMockDeleteGroupsRequest(t TestReporter) *MockDeleteGroupsResponse {
+	return &MockDeleteGroupsResponse{}
+}
+
+func (m *MockDeleteGroupsResponse) SetDeletedGroups(groups []string) *MockDeleteGroupsResponse {
+	m.deletedGroups = groups
+	return m
+}
+
+func (m *MockDeleteGroupsResponse) For(reqBody versionedDecoder) encoder {
+	resp := &DeleteGroupsResponse{
+		GroupErrorCodes: map[string]KError{},
+	}
+	for _, group := range m.deletedGroups {
+		resp.GroupErrorCodes[group] = ErrNoError
+	}
+	return resp
+}