ks[i], ks[j] = ks[j], ks[i]
	}
	return strings.Join(ks, ".")
}

// Retrieves list of entries under the key passed.
// Note that this method fetches entries upto only two levels deep.
func (c *CoreDNS) list(key string, domain bool) ([]SrvRecord, error) {
	ctx, cancel := context.WithTimeout(context.Background(), defaultContextTimeout)
	r, err := c.etcdClient.Get(ctx, key, clientv3.WithPrefix())

		// ListObjectsResult-36 list with nextmarker prefix and maxKeys set to 1.
		36: {
			IsTruncated: true,
			Prefixes:    []string{"dir/day_id=2017-10-10/"},
		},
		// ListObjectsResult-37 list with prefix match 2 levels deep
		37: {
			IsTruncated: false,
			Objects: []ObjectInfo{
				{Name: "foo/201910/1112"},
				{Name: "foo/201910/1122"},
			},
		},
		// ListObjectsResult-38 list with prefix match 1 level deep

		unlockOnDefer = true
	}

	checkPrecondFn := opts.CheckPrecondFn
	opts.CheckPrecondFn = nil // do not need to apply pre-conditions at lower layer.
	opts.NoLock = true        // no locks needed at lower levels for getObjectInfo()
	objInfo, zIdx, err := z.getLatestObjectInfoWithIdx(ctx, bucket, object, opts)
	if err != nil {
		if objInfo.DeleteMarker {
			if opts.VersionID == "" {
				return &GetObjectReader{