Add grpc plugin (#2758)

* Add grpc plugin

* remove stale readmes

server/grpc/extractor_test.go

@@ -0,0 +1,64 @@
+package grpc
+
+import (
+	"context"
+	"reflect"
+	"testing"
+
+	"go-micro.dev/v5/registry"
+)
+
+type testHandler struct{}
+
+type testRequest struct{}
+
+type testResponse struct{}
+
+func (t *testHandler) Test(ctx context.Context, req *testRequest, rsp *testResponse) error {
+	return nil
+}
+
+func TestExtractEndpoint(t *testing.T) {
+	handler := &testHandler{}
+	typ := reflect.TypeOf(handler)
+
+	var endpoints []*registry.Endpoint
+
+	for m := 0; m < typ.NumMethod(); m++ {
+		if e := extractEndpoint(typ.Method(m)); e != nil {
+			endpoints = append(endpoints, e)
+		}
+	}
+
+	if i := len(endpoints); i != 1 {
+		t.Errorf("Expected 1 endpoint, have %d", i)
+	}
+
+	if endpoints[0].Name != "Test" {
+		t.Errorf("Expected handler Test, got %s", endpoints[0].Name)
+	}
+
+	if endpoints[0].Request == nil {
+		t.Error("Expected non nil request")
+	}
+
+	if endpoints[0].Response == nil {
+		t.Error("Expected non nil request")
+	}
+
+	if endpoints[0].Request.Name != "testRequest" {
+		t.Errorf("Expected testRequest got %s", endpoints[0].Request.Name)
+	}
+
+	if endpoints[0].Response.Name != "testResponse" {
+		t.Errorf("Expected testResponse got %s", endpoints[0].Response.Name)
+	}
+
+	if endpoints[0].Request.Type != "testRequest" {
+		t.Errorf("Expected testRequest type got %s", endpoints[0].Request.Type)
+	}
+
+	if endpoints[0].Response.Type != "testResponse" {
+		t.Errorf("Expected testResponse type got %s", endpoints[0].Response.Type)
+	}
+}