• RPC

  • What is an RPC Framework?

What is an RPC Framework?

🔹 What is an RPC Framework?

An RPC (Remote Procedure Call) framework is a set of tools, libraries, and protocols that allow applications to execute functions or procedures on a remote server as if they were local functions.

✅ Purpose: Simplifies communication between distributed systems, microservices, and cloud applications.
✅ Example Use Case: A frontend app calling a backend function on a remote server without worrying about networking details.

🔹 How Does an RPC Framework Work?

1️⃣ Client makes an RPC request (calls a function remotely).
2️⃣ RPC framework serializes the request (converts data into a transportable format).
3️⃣ Server receives and processes the request.
4️⃣ RPC framework deserializes the response and returns it to the client.

📌 Example of an RPC Call Flow:

Client  ──> RPC Framework ──> Network ──> Server  
Client  <── RPC Framework <── Network <── Server Response

💡 Think of it like calling a function, but it runs on another server! 🚀

🔹 Popular RPC Frameworks

| RPC Framework | Used For | Protocol | Serialization Format |
|------------------|-------------|-------------|----------------------|
| gRPC | Microservices, Cloud APIs | HTTP/2 | Protocol Buffers (ProtoBuf) |
| Apache Thrift | Cross-language RPC | TCP, HTTP | Compact Binary Format |
| JSON-RPC | Web APIs, JavaScript-based Apps | HTTP, WebSockets | JSON |
| XML-RPC | Legacy Systems | HTTP | XML |
| ZeroMQ (ØMQ) | High-performance messaging | Custom (No built-in protocol) | Custom |
| Dapr | Cloud-Native Applications | HTTP/gRPC | JSON/ProtoBuf |

🔹 Why Use an RPC Framework?

✅ Simplicity → Developers call remote functions like local functions.
✅ High Performance → Many frameworks (like gRPC) use binary serialization for fast data transmission.
✅ Cross-Language Support → Works across different programming languages (e.g., Python client calling a Go server).
✅ Streaming Support → Some frameworks (e.g., gRPC) support bidirectional streaming.

🔹 gRPC Example (Python)

Define an RPC Service (hello.proto):

syntax = "proto3";

service Greeter {
  rpc SayHello (HelloRequest) returns (HelloReply);
}

message HelloRequest {
  string name = 1;
}

message HelloReply {
  string message = 1;
}

✅ The RPC framework handles serialization, networking, and responses automatically!

🎯 Final Thoughts

🔥 An RPC framework helps build high-performance distributed systems efficiently! 🔥
✅ Best for: Microservices, Cloud APIs, and High-Speed Communication.
✅ Best choice: gRPC for modern systems, Thrift for cross-language, and JSON-RPC for web apps.

Would you like a hands-on guide to implementing gRPC or Thrift in Python, Go, or Java? 🚀