add context for registry (#716)

* add context for registry

app.go

@@ -81,7 +81,7 @@ func (a *App) Run() error {
 		})
 	}
 	if a.opts.registry != nil {
-		if err := a.opts.registry.Register(a.instance); err != nil {
+		if err := a.opts.registry.Register(a.opts.ctx, a.instance); err != nil {
 			return err
 		}
 	}
@@ -106,7 +106,7 @@ func (a *App) Run() error {
 // Stop gracefully stops the application.
 func (a *App) Stop() error {
 	if a.opts.registry != nil {
-		if err := a.opts.registry.Deregister(a.instance); err != nil {
+		if err := a.opts.registry.Deregister(a.opts.ctx, a.instance); err != nil {
 			return err
 		}
 	}

registry/registry.go

@@ -1,15 +1,17 @@
 package registry
 
+import "context"
+
 // Registry is service registry.
 type Registry interface {
 	// Register the registration.
-	Register(service *ServiceInstance) error
+	Register(ctx context.Context, service *ServiceInstance) error
 	// Deregister the registration.
-	Deregister(service *ServiceInstance) error
+	Deregister(ctx context.Context, service *ServiceInstance) error
 	// Service return the service instances in memory according to the service name.
-	Service(name string) ([]*ServiceInstance, error)
+	Service(ctx context.Context, name string) ([]*ServiceInstance, error)
 	// Watch creates a watcher according to the service name.
-	Watch(name string) (Watcher, error)
+	Watch(ctx context.Context, name string) (Watcher, error)
 }
 
 // Watcher is service watcher.

transport/grpc/resolver/discovery/builder.go

@@ -1,6 +1,8 @@
 package discovery
 
 import (
+	"context"
+
 	"github.com/go-kratos/kratos/v2/log"
 	"github.com/go-kratos/kratos/v2/registry"
 	"google.golang.org/grpc/resolver"
@@ -36,7 +38,7 @@ func NewBuilder(r registry.Registry, opts ...Option) resolver.Builder {
 }
 
 func (d *builder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (resolver.Resolver, error) {
-	w, err := d.registry.Watch(target.Endpoint)
+	w, err := d.registry.Watch(context.Background(), target.Endpoint)
 	if err != nil {
 		return nil, err
 	}