Spring gRPC Example

This repository contains two separate Spring Boot projects demonstrating a gRPC server and client. It showcases the four main types of gRPC communication patterns: Unary RPC, Server Streaming RPC, Client Streaming RPC, and Bidirectional Streaming RPC.

Projects

grpc-server

This project contains the gRPC server implementation. It includes services such as UnaryService, ServerStreamingService, ClientStreamingService, and BidirectionalStreamingService.

grpc-client

This project contains the gRPC client implementation which interacts with the gRPC server using the mentioned services.

Prerequisites

Java 17
Maven

Running the Projects

Running the Server

Navigate to the grpc-server directory:
```
cd spring-grpc-example/grpc-server
```
Run the server application:
```
./mvnw spring-boot:run
```
You should see logs indicating the server has started on the specified port:
```
🚀 gRPC Server has successfully started on port 9090.
```

Running the Client

Open a new terminal and navigate to the grpc-client directory:
```
cd spring-grpc-example/grpc-client
```
Run the client application:
```
./mvnw spring-boot:run
```

You should see logs indicating the client has initialized the system and started the different gRPC interactions:

Unary response: Unary response: Performing unary call...
Sent client message: Client message 1
Received from server streaming: Server streaming response 1: Performing server streaming call...
Received from bidirectional streaming: Response: Ping

Project Structure

grpc-server: Contains the gRPC server code.
grpc-client: Contains the gRPC client code.
proto/unary.proto: Protocol Buffers definition file used by both server and client for the unary service.
proto/server_streaming.proto: Protocol Buffers definition file used by both server and client for the server streaming service.
proto/client_streaming.proto: Protocol Buffers definition file used by both server and client for the client streaming service.
proto/bidirectional_streaming.proto: Protocol Buffers definition file used by both server and client for the bidirectional streaming service.

Example Protobuf Definitions

Unary Service (unary.proto)

syntax = "proto3";

option java_multiple_files = true;
option java_package = "com.example.grpc";
option java_outer_classname = "UnaryProto";

package unary;

// The Unary service definition.
service UnaryService {
  rpc UnaryCall (UnaryRequest) returns (UnaryResponse);
}

// The request message containing the unary call message.
message UnaryRequest {
  string message = 1;
}

// The response message containing the unary call response.
message UnaryResponse {
  string message = 1;
}

Server Streaming Service (server_streaming.proto)

syntax = "proto3";

option java_multiple_files = true;
option java_package = "com.example.grpc";
option java_outer_classname = "ServerStreamingProto";

package serverstreaming;

// The Server Streaming service definition.
service ServerStreamingService {
  rpc ServerStreamingCall (ServerStreamingRequest) returns (stream ServerStreamingResponse);
}

// The request message containing the server streaming call message.
message ServerStreamingRequest {
  string message = 1;
}

// The response message containing the server streaming response.
message ServerStreamingResponse {
  string message = 1;
}

Dependencies

Spring Boot 3
gRPC
Protocol Buffers

Contributing

Feel free to fork this repository and contribute by submitting a pull request.

License

This project is licensed under the MIT License.

merih-sakarya/spring-boot-grpc-example