PLT-8233: Purge ChannelMemberHistory Data when Data Retention Job runs (#7937)

* Changed the channel member history purge function to match pattern established by other data retention purge methods

* Simplifying the channel member history store and associated tests

* Regenerating mocks

* Using a constant

store/storetest/channel_member_history_store.go

@@ -6,6 +6,8 @@ package storetest
 import (
 	"testing"
 
+	"math"
+
 	"github.com/mattermost/mattermost-server/model"
 	"github.com/mattermost/mattermost-server/store"
 	"github.com/stretchr/testify/assert"
@@ -15,7 +17,7 @@ func TestChannelMemberHistoryStore(t *testing.T, ss store.Store) {
 	t.Run("Log Join Event", func(t *testing.T) { testLogJoinEvent(t, ss) })
 	t.Run("Log Leave Event", func(t *testing.T) { testLogLeaveEvent(t, ss) })
 	t.Run("Get Users In Channel At Time", func(t *testing.T) { testGetUsersInChannelAt(t, ss) })
-	t.Run("Purge History", func(t *testing.T) { testPurgeHistoryBefore(t, ss) })
+	t.Run("Purge History", func(t *testing.T) { testPermanentDeleteBatch(t, ss) })
 }
 
 func testLogJoinEvent(t *testing.T, ss store.Store) {
@@ -135,7 +137,7 @@ func testGetUsersInChannelAt(t *testing.T, ss store.Store) {
 	assert.Len(t, channelMembers, 0)
 }
 
-func testPurgeHistoryBefore(t *testing.T, ss store.Store) {
+func testPermanentDeleteBatch(t *testing.T, ss store.Store) {
 	// create a test channel
 	channel := model.Channel{
 		TeamId:      model.NewId(),
@@ -171,8 +173,11 @@ func testPurgeHistoryBefore(t *testing.T, ss store.Store) {
 	channelMembers := store.Must(ss.ChannelMemberHistory().GetUsersInChannelDuring(joinTime+10, leaveTime-10, channel.Id)).([]*model.ChannelMemberHistory)
 	assert.Len(t, channelMembers, 2)
 
-	// but if we purge the old data, only the user that didn't leave is left
-	store.Must(ss.ChannelMemberHistory().PurgeHistoryBefore(leaveTime, channel.Id))
+	// the permanent delete should delete at least one record
+	rowsDeleted := store.Must(ss.ChannelMemberHistory().PermanentDeleteBatch(leaveTime, math.MaxInt64)).(int64)
+	assert.NotEqual(t, int64(0), rowsDeleted)
+
+	// after the delete, there should be one less member in the channel
 	channelMembers = store.Must(ss.ChannelMemberHistory().GetUsersInChannelDuring(joinTime+10, leaveTime-10, channel.Id)).([]*model.ChannelMemberHistory)
 	assert.Len(t, channelMembers, 1)
 	assert.Equal(t, user2.Id, channelMembers[0].UserId)

store/storetest/mocks/ChannelMemberHistoryStore.go

@@ -60,13 +60,13 @@ func (_m *ChannelMemberHistoryStore) LogLeaveEvent(userId string, channelId stri
 	return r0
 }
 
-// PurgeHistoryBefore provides a mock function with given fields: time, channelId
-func (_m *ChannelMemberHistoryStore) PurgeHistoryBefore(time int64, channelId string) store.StoreChannel {
-	ret := _m.Called(time, channelId)
+// PermanentDeleteBatch provides a mock function with given fields: endTime, limit
+func (_m *ChannelMemberHistoryStore) PermanentDeleteBatch(endTime int64, limit int64) store.StoreChannel {
+	ret := _m.Called(endTime, limit)
 
 	var r0 store.StoreChannel
-	if rf, ok := ret.Get(0).(func(int64, string) store.StoreChannel); ok {
-		r0 = rf(time, channelId)
+	if rf, ok := ret.Get(0).(func(int64, int64) store.StoreChannel); ok {
+		r0 = rf(endTime, limit)
 	} else {
 		if ret.Get(0) != nil {
 			r0 = ret.Get(0).(store.StoreChannel)