MM-60240 Sanitize Channels based on user permissions (#28086)

* initial commit

* add unit tests

* update tests, self review

* update tests to verify something returned.

* update app-layer

* update unit tests

* fix tests

* add check for PermissionSysconsoleReadComplianceDataRetentionPolicy

* revert package-lock

* review suggestions

---------

Co-authored-by: Mattermost Build <build@mattermost.com>

server/public/model/channel.go

@@ -356,6 +356,15 @@ func (o *Channel) GetOtherUserIdForDM(userId string) string {
 	return otherUserId
 }
 
+func (o *Channel) Sanitize() Channel {
+	return Channel{
+		Id:          o.Id,
+		TeamId:      o.TeamId,
+		Type:        o.Type,
+		DisplayName: o.DisplayName,
+	}
+}
+
 func (t ChannelType) MarshalJSON() ([]byte, error) {
 	return json.Marshal(string(t))
 }

server/public/model/channel_test.go

@@ -114,3 +114,49 @@ func TestGetGroupNameFromUserIds(t *testing.T) {
 
 	require.LessOrEqual(t, len(name), ChannelNameMaxLength)
 }
+
+func TestSanitize(t *testing.T) {
+	schemaId := NewId()
+	o := Channel{
+		Id:                NewId(),
+		CreateAt:          1,
+		UpdateAt:          1,
+		DeleteAt:          1,
+		Name:              NewId(),
+		DisplayName:       NewId(),
+		Header:            NewId(),
+		Purpose:           NewId(),
+		LastPostAt:        1,
+		TotalMsgCount:     1,
+		ExtraUpdateAt:     1,
+		CreatorId:         NewId(),
+		SchemeId:          &schemaId,
+		Props:             make(map[string]any),
+		GroupConstrained:  NewPointer(true),
+		Shared:            NewPointer(true),
+		TotalMsgCountRoot: 1,
+		PolicyID:          &schemaId,
+		LastRootPostAt:    1,
+	}
+	s := o.Sanitize()
+
+	require.NotEqual(t, "", s.Id)
+	require.Equal(t, int64(0), s.CreateAt)
+	require.Equal(t, int64(0), s.UpdateAt)
+	require.Equal(t, int64(0), s.DeleteAt)
+	require.Equal(t, "", s.Name)
+	require.NotEqual(t, "", s.DisplayName)
+	require.Equal(t, "", s.Header)
+	require.Equal(t, "", s.Purpose)
+	require.Equal(t, int64(0), s.LastPostAt)
+	require.Equal(t, int64(0), s.TotalMsgCount)
+	require.Equal(t, int64(0), s.ExtraUpdateAt)
+	require.Equal(t, "", s.CreatorId)
+	require.Nil(t, s.SchemeId)
+	require.Nil(t, s.Props)
+	require.Nil(t, s.GroupConstrained)
+	require.Nil(t, s.Shared)
+	require.Equal(t, int64(0), s.TotalMsgCountRoot)
+	require.Nil(t, s.PolicyID)
+	require.Equal(t, int64(0), s.LastRootPostAt)
+}