Add service registry

registry/service/service.go

@@ -0,0 +1,155 @@
+// Package service uses the registry service
+package service
+
+import (
+	"context"
+	"time"
+
+	"github.com/micro/go-micro/client"
+	"github.com/micro/go-micro/registry"
+	pb "github.com/micro/go-micro/registry/proto"
+)
+
+var (
+	// The default service name
+	DefaultService = "go.micro.service"
+)
+
+type serviceRegistry struct {
+	opts registry.Options
+	// name of the registry
+	name string
+	// address
+	address []string
+	// client to call registry
+	client pb.RegistryService
+}
+
+func (s *serviceRegistry) callOpts() []client.CallOption {
+	var opts []client.CallOption
+
+	// set registry address
+	if len(s.address) > 0 {
+		opts = append(opts, client.WithAddress(s.address...))
+	}
+
+	// set timeout
+	if s.opts.Timeout > time.Duration(0) {
+		opts = append(opts, client.WithRequestTimeout(s.opts.Timeout))
+	}
+
+	return opts
+}
+
+func (s *serviceRegistry) Init(opts ...registry.Option) error {
+	for _, o := range opts {
+		o(&s.opts)
+	}
+	return nil
+}
+
+func (s *serviceRegistry) Options() registry.Options {
+	return s.opts
+}
+
+func (s *serviceRegistry) Register(srv *registry.Service, opts ...registry.RegisterOption) error {
+	var options registry.RegisterOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// register the service
+	_, err := s.client.Register(context.TODO(), toProto(srv), s.callOpts()...)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (s *serviceRegistry) Deregister(srv *registry.Service) error {
+	// deregister the service
+	_, err := s.client.Deregister(context.TODO(), toProto(srv), s.callOpts()...)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (s *serviceRegistry) GetService(name string) ([]*registry.Service, error) {
+	rsp, err := s.client.GetService(context.TODO(), &pb.GetRequest{
+		Service: name,
+	}, s.callOpts()...)
+
+	if err != nil {
+		return nil, err
+	}
+
+	var services []*registry.Service
+	for _, service := range rsp.Services {
+		services = append(services, toService(service))
+	}
+	return services, nil
+}
+
+func (s *serviceRegistry) ListServices() ([]*registry.Service, error) {
+	rsp, err := s.client.ListServices(context.TODO(), &pb.ListRequest{}, s.callOpts()...)
+	if err != nil {
+		return nil, err
+	}
+
+	var services []*registry.Service
+	for _, service := range rsp.Services {
+		services = append(services, toService(service))
+	}
+
+	return services, nil
+}
+
+func (s *serviceRegistry) Watch(opts ...registry.WatchOption) (registry.Watcher, error) {
+	var options registry.WatchOptions
+	for _, o := range opts {
+		o(&options)
+	}
+
+	stream, err := s.client.Watch(context.TODO(), &pb.WatchRequest{
+		Service: options.Service,
+	}, s.callOpts()...)
+
+	if err != nil {
+		return nil, err
+	}
+
+	return newWatcher(stream), nil
+}
+
+func (s *serviceRegistry) String() string {
+	return s.name
+}
+
+// NewRegistry returns a new registry service client
+func NewRegistry(opts ...registry.Option) registry.Registry {
+	var options registry.Options
+	for _, o := range opts {
+		o(&options)
+	}
+
+	// use mdns to find the service registry
+	mReg := registry.NewRegistry()
+
+	// create new client with mdns
+	cli := client.NewClient(
+		client.Registry(mReg),
+	)
+
+	// service name
+	// TODO: accept option
+	name := DefaultService
+
+	return &serviceRegistry{
+		opts:    options,
+		name:    name,
+		address: options.Addrs,
+		client:  pb.NewRegistryService(name, cli),
+	}
+}