update examples (#1108)

* update examples/README.md and delete the middleware.Chain contained in examples

* update examples/README.md

examples/README.md

@@ -1 +1,14 @@
 # examples
+
+- examples/blog is simple crud project.
+- examples/config is kratos config example.
+- examples/errors is kratos errors example, it is generated through proto-gen-go-errors.
+- examples/helloworld is helloworld example.
+- examples/http is transport/http some examples of usage.
+- examples/log is log example, including、logger、helper、filter、valuer, etc.
+- examples/metadata is metadata example.
+- examples/metrics is metrics example, in the example, prom is used to collect data.
+- examples/registry is registration and discovery examples,including Etcd, Consul, Nacos.
+- examples/traces is middleware/tracing example，middleware/tracing is implemented by opentelemetry.
+- examples/validate is middleware/validate example, the verification code is generated by proto-gen-validate.
+- examples/ws is implementation of transport interface with websocket example.

examples/helloworld/client/main.go

@@ -6,7 +6,6 @@ import (
 
 	pb "github.com/go-kratos/kratos/examples/helloworld/helloworld"
 	"github.com/go-kratos/kratos/v2/errors"
-	"github.com/go-kratos/kratos/v2/middleware"
 	"github.com/go-kratos/kratos/v2/middleware/recovery"
 	transgrpc "github.com/go-kratos/kratos/v2/transport/grpc"
 	transhttp "github.com/go-kratos/kratos/v2/transport/http"
@@ -50,9 +49,7 @@ func callGRPC() {
 		context.Background(),
 		transgrpc.WithEndpoint("127.0.0.1:9000"),
 		transgrpc.WithMiddleware(
-			middleware.Chain(
-				recovery.Recovery(),
-			),
+			recovery.Recovery(),
 		),
 	)
 	if err != nil {