Add a method filter for interceptors #459

CAFxX · 2021-09-17T07:13:18Z

This PR is an RFC for a conditional interceptor for specific gRPC methods.

It allows applying an interceptor (sub)chain only to specific methods, or to all but some specific methods, e.g.

// Method1 -> authInterceptor
// Method2 -> authInterceptor, otherInterceptor
// all other methods -> otherInterceptor
ChainUnaryServer(
  // apply the authInterceptor only to `Method1` and `Method2`
  UnaryServerMethods(authInterceptor, true, "/package.service/Method1", "/package.service/Method2"),
  // apply otherInterceptor to all methods apart from `Method1`
  UnaryServerMethods(otherInterceptor, false, "/package.service/Method1"),
)

update: I see we have #364 in v2 (although it's unreleased)

CAFxX · 2021-09-17T07:15:45Z

filter/server_interceptors.go

+/*
+func UnaryServerMethodsInterceptor(interceptor grpc.UnaryServerInterceptor, allowlist bool, methods ...string) grpc.UnaryServerInterceptor {
+	m := newMatchlist(methods, allowlist)
+
+	return UnaryServerConditionInterceptor(interceptor, func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo) bool {
+		return m.match(info.FullMethod)
+	})
+}
+
+func UnaryServerConditionInterceptor(interceptor grpc.UnaryServerInterceptor, condition func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo) bool) grpc.UnaryServerInterceptor {
+	if interceptor == nil {
+		panic("nil interceptor")
+	}
+	return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
+		if condition(ctx, req, info) {
+			return interceptor(ctx, req, info, handler)
+		}
+		return handler(ctx, req)
+	}
+}
+*/


this is an alternate implementation style in case we want to support plugging in arbitrary conditions

add a method filter

30f9367

CAFxX commented Sep 17, 2021

View reviewed changes

devnev added the v1 label Oct 8, 2022

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add a method filter for interceptors #459

Add a method filter for interceptors #459

CAFxX commented Sep 17, 2021 •

edited

CAFxX Sep 17, 2021

Add a method filter for interceptors #459

Are you sure you want to change the base?

Add a method filter for interceptors #459

Conversation

CAFxX commented Sep 17, 2021 • edited

CAFxX Sep 17, 2021

Choose a reason for hiding this comment

CAFxX commented Sep 17, 2021 •

edited