Пример #1
1
func (l *labelWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
	md, _ := metadata.FromContext(ctx)

	labels := make(map[string]string)

	for k, v := range md {
		if strings.HasPrefix(k, LabelPrefix) {
			key := strings.TrimPrefix(k, LabelPrefix)
			key = strings.ToLower(key)
			labels[key] = strings.ToLower(v)
		}
	}

	filter := func(services []*registry.Service) []*registry.Service {
		var filtered []*registry.Service

	SERVICE:
		for _, service := range services {
			// check labels for the service
			for lk, lv := range labels {
				// if we match then append the service and return
				if v := service.Metadata[lk]; v == lv {
					filtered = append(filtered, service)
					continue SERVICE
				}
			}

			var nodes []*registry.Node

		NODE:
			for _, node := range service.Nodes {
				// check labels against the node
				for lk, lv := range labels {
					// if it matches then append node
					if v := node.Metadata[lk]; v == lv {
						nodes = append(nodes, node)
						continue NODE
					}
				}
			}

			if len(nodes) > 0 {
				service.Nodes = nodes
				filtered = append(filtered, service)
			}
		}

		return filtered
	}

	callOptions := append(opts, client.WithSelectOption(
		selector.Filter(filter),
	))

	return l.Client.Call(ctx, req, rsp, callOptions...)
}
Пример #2
0
func (dc *dcWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
	md, _ := c.GetMetadata(ctx)

	filter := func(services []*registry.Service) []*registry.Service {
		for _, service := range services {
			var nodes []*registry.Node
			for _, node := range service.Nodes {
				if node.Metadata["datacenter"] == md["datacenter"] {
					nodes = append(nodes, node)
				}
			}
			service.Nodes = nodes
		}
		return services
	}

	callOptions := append(opts, client.WithSelectOption(
		selector.Filter(filter),
	))

	fmt.Printf("[DC Wrapper] filtering for datacenter %s\n", md["datacenter"])
	return dc.Client.Call(ctx, req, rsp, callOptions...)
}