Full gRPC Support with tRPC Middleware

This project demonstrates a full-stack setup using gRPC as the backend service with a tRPC server acting as a bridge to expose gRPC methods to a Svelte frontend.

graph LR
    subgraph Go_Server
        A[gRPC Server - Engine]
    end

    subgraph Node_Server
        B[gRPC Client - Node-TS]
        C[tRPC Server - Node-TS]
    end

    subgraph Svelte_Frontend
        D[tRPC Client - Svelte]
    end

    A -->|gRPC| B
    B -->|tRPC| C
    C -->|tRPC over HTTP/WebSocket| D

Overview

Architecture:

• gRPC Server (Go): Provides core gRPC services.
• tRPC Server (Node.js with TypeScript): Acts as a middleware that communicates with the Go gRPC server via a gRPC client and exposes APIs to the frontend.
• Svelte Frontend: Connects to the tRPC server and provides a user interface.

Data Flow:

1. Go gRPC Server serves data on defined protobuf methods.
2. tRPC Server acts as a gRPC client to the Go server, exposing the same methods over HTTP/WebSocket via tRPC.
3. Svelte Client interacts with the tRPC server to access gRPC functionality.

Setup Guide

1. Set Up the Go gRPC Server

1. Navigate to the remote directory.
2. Run go run server.go to start the Go gRPC server.
3. Ensure it listens on a specified port (e.g., localhost:50051).

   2. Set Up the tRPC Server

4. In the trpc directory, install dependencies:

   npm install
   

5. Configure client.ts to connect to the Go server as a gRPC client using generated service_pb.js and service_grpc_pb.js files.
6. Set up router.ts to expose methods via tRPC.
7. Run the server with:

   node server.ts
   

8. The tRPC server should now be accessible (e.g., on http://localhost:4000 or via WebSocket if subscriptions are required).

3. Set Up the Svelte Client

1. Install dependencies in the root Svelte project directory:

   npm install
   

2. Configure client.ts in src/lib/trpc to connect to the tRPC server.

3. Use pages in src/routes (e.g., GetStateInfo.svelte, Chat.svelte) to call tRPC methods.

Running the Full Setup

• Run the Go gRPC server by navigating to the remote directory and using:

  go run server.go
  

• Run the tRPC server in the trpc directory:

  node server.ts
  

• Run the Svelte client in the root directory:

  npm run dev
  

Notes

• WebSockets: Ensure WebSocket support on the tRPC server for real-time subscriptions.
• Protobuf Generation: Use protobuf_generate.sh in remote/protobuf to regenerate Go and Node.js protobuf files if .proto files are updated.