gRPC VS ZeroMQ

gRPC, built on HTTP/2, inherently supports flow control. The server can push updates, but it must also respect flow control signals from the client, ensuring that it doesn't send data faster than what the client can handle.

Yes, grpc_cli tool uses essentially the same mechanism except implemented as a grpc service rather than as a stubby service. The basic principle of both is implementing the C++ proto library's DescriptorDatabase interface with cached recursive queries of (usually) the server's compiled in FileDescriptorProtos.

See also https://github.com/grpc/grpc/blob/master/doc/server-reflecti...

The primary difference between what grpc does and what stubby does is that grpc uses a stream to ensure that the reflection requests all go to the same server to avoid incompatible version skew and duplicate proto transmissions. With that said, in practice version skew is rarely a problem for grpc_cli style "issue a single RPC" usecases: even if requests do go to two or more different versions of a binary that might have incompatible proto graphs, it is very common for the request and response and RPC to all be in the same proto file so you only need to make one RPC in the first place unless you're using an extension mechanism like proto2 extensions or google.protobuf.Any.

While gRPC and Apache Thrift have served the microservice architecture well, CloudWeGo's advanced features and performance metrics set it apart as a promising open source solution for the future.

The loadBalancingConfig is what we use in order to decide which policy to go for (round_robin in this case). This JSON representation is based on a protobuf message, then why does the name resolver returns it in the JSON format? The main reason is that loadBalancingConfig is a oneof field inside the proto message and so it can not contain values unknown to the gRPC if used in the proto format. The JSON representation does not have this requirement so we can use a custom loadBalancingConfig .

The Dart implementation of gRPC which puts mobile and HTTP/2 first. It's built and maintained by the Dart team. gRPC is a high-performance RPC (remote procedure call) framework that is optimized for efficient data transfer.

gRPC is a high-performance, open-source RPC (Remote Procedure Call) framework initially developed by Google. It uses Protocol Buffers for serialization and supports bidirectional streaming.

In general, tunneling through HTTP2 turns out to be a great choice. There is a RPC protocol built on top of HTTP2: gRPC[1].

This is because HTTP2 is great at exploiting a TCP connection to transmit and receive multiple data structures concurrently - multiplexing.

There may not be a reason to use HTTP3 however, as QUIC already provides multiplexing.

I expect that in the future most communications will be over encrypted HTTP2 and QUIC simply because middleware creators can not resist to discriminate.

[1] <https://grpc.io>

Even in the https://grpc.io blog says this

gRPC

Slightly OT:

Are ZeroMQ and NanoMQ still widely used (and recommended)?

https://github.com/zeromq/libzmq

https://github.com/nanomq/nanomq

Remarkable, up until recently, requests for a new release were sumewhat brusquely rejected and marked as spam.

https://github.com/zeromq/libzmq/issues/4455

I wonder what made the maintainer change his mind.

FP Libraries: gRPC, ZeroMQ, and AREG are examples of libraries with a special focus on providing possibilities for Interprocess Communication. Developed using C++, they facilitate communication through predefined APIs, emphasizing functional programming concepts.

Unlikely, but they seem to be different things altogether. BlazingMQ appears to be a traditional message queue (think ActiveMQ), with message peristence. ZeroMQ is more of a network middleware (think Tibco Rendezvous), and does not include persistence.

BlazingMQ also appears to be more of a "platform" or "service" that an app can use (sort of like Oracle, say) -- ZeroMQ includes libraries that one can use to build an app, service or platform, but none is provided "out of the box".

Which makes it harder to get started with ZeroMQ, since by definition every ZeroMQ app is essentially built "from scratch".

If you're interested in ZeroMQ, you may want to check out OZ (https://github.com/nyfix/OZ), which is a Rendezvous-like platform that uses the OpenMAMA API (https://github.com/finos/OpenMAMA) and ZeroMQ (https://github.com/zeromq/libzmq) transport to provide a full-featured network middleware implementation. OZ has been used in our shop since 2020 handling approx 50MM high-value messages per day on our global FIX network.

-- Using src='https://github.com/zeromq/libzmq/releases/download/v4.3.4/zeromq-4.3.4.tar.gz'

Just check copying file in source repo https://github.com/zeromq/libzmq

I think the situation is more subtle than the poster admits.

No, ZeroMQ and successors do not tell you about socket state. You can't detect disconnection or reconnection. But then if a TCP connection fails in some way that does not lead to disconnection (packets getting dropped, remote machine powers down), it can't possibly tell you about that either, but you still need to deal with it. So in any case, you need some sort of application-level error detection and recovery; you need heartbeats, and serial numbers in messages, and a protocol for explicitly restarting a connection and performing the initial handshake. And once you have that, explicit connection events from ZeroMQ are much less important.

Admittedly, given that this is a TCP transport, reporting reconnections would still be useful, because TCP won't ever drop messages from the interior of a sequence itself (if it delivers 15, it has delivered 1 - 14 already), so you shouldn't need the serial numbers.

And if it's really not possible to detect authentication failures, than that seems rubbish. And it seems that is indeed the case: https://github.com/zeromq/libzmq/issues/3505

From https://github.com/zeromq/libzmq