ep := &EndpointShards{
		Shards:          map[ShardKey][]*IstioEndpoint{},
		ServiceAccounts: sets.String{},
	}
	e.shardsBySvc[serviceName][namespace] = ep
	// Clear the cache here to avoid race in cache writes.
	e.clearCacheForService(serviceName, namespace)
	return ep, true
}

func (e *EndpointIndex) DeleteServiceShard(shard ShardKey, serviceName, namespace string, preserveKeys bool) {
	e.mu.Lock()

		return "", err
	}
	return meta.GetResourceVersion(), nil
}

// Patch applies only the modifications made in the PatchFunc rather than doing a full replace. Useful to avoid
// read-modify-write conflicts when there are many concurrent-writers to the same resource.
func (cl *Client) Patch(orig config.Config, patchFn config.PatchFunc) (string, error) {
	modified, patchType := patchFn(orig.DeepCopy())

		removed := subscribed.DeleteAll(currentResources...)
		resp.RemovedResources = sets.SortedList(removed)
	}
	var newResourceNames []string
	if shouldSetWatchedResources(w) {
		// Set the new watched resources. Do not write to w directly, as it can be a copy from the 'filtered' logic above
		if usedDelta {
			// Apply the delta
			newResourceNames = sets.SortedList(sets.New(w.ResourceNames...).
				DeleteAll(resp.RemovedResources...).