grpc-nodejs

A Node.js application demonstrating bidirectional streaming using gRPC with three services:

1. Greet Service
2. Calculator Service
3. Blog Service

Prerequisites

• Node.js (v16 or later)
• gRPC Tools
• Protobuf Compiler
• Docker (for MongoDB)

Installation

1. Clone the repository:

git clone https://github.com/mariscalromeroalejandro/gRPC-nodejs
cd grpc-nodejs

2. Install dependencies:

npm install

Generate Protobuf Files

To generate the gRPC client and server code from .proto files, run:

npm run pb:gen

This command uses the gen.sh script located in the scripts folder and processes greet, calculator, and blog services.

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Running the Services

Enabling TLS/SSL:

To enable TLS/SSL, set the tls variable to true in both the client and server main() functions. Ensure the following files are available in the ./ssl directory:

• ca.crt - Root Certificate
• server.crt - Server Certificate
• server.pem - Private Key

Run the ssl:gen script to generate these files:

npm run ssl:gen

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Greet Service

• Start the Greet Server:

npm run greet:server

• Run the Greet Client:

npm run greet:client

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Calculator Service

• Start the Calculator Server:

npm run calculator:server

• Run the Calculator Client:

npm run calculator:client

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Blog Service

The Blog Service demonstrates CRUD operations with MongoDB using gRPC.

Starting MongoDB:

Before running the Blog Service, start MongoDB using Docker:

npm run blog:db

Start the Blog Server:

npm run blog:server

Run the Blog Client:

npm run blog:client

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Client Implementation

Each service has its own client implementation located in its respective folder (greet/client, calculator/client, blog/client).

Example usage for the Blog client:

function main() {
    const creds = grpc.credentials.createInsecure();
    const client = new BlogServiceClient('localhost:50051', creds);

    const req = new Blog()
        .setAuthorId('Alex')
        .setTitle('My First Blog')
        .setContent('This is a sample blog post.');

    client.createBlog(req, (err, res) => {
        if (err) {
            console.error('Error:', err.message);
            return;
        }
        console.log('Blog created with ID:', res.getId());
    });
}

main();

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Project Structure

grpc-nodejs/
├── greet/
│   ├── client/
│   ├── server/
│   └── proto/
├── calculator/
│   ├── client/
│   ├── server/
│   └── proto/
├── blog/
│   ├── client/
│   ├── server/
│   ├── proto/
│   └── docker-compose.yml
├── scripts/
│   └── gen.sh
├── ssl/
│   └── (SSL Certificates)
├── package.json
└── README.md

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Dependencies

• @grpc/grpc-js: gRPC library for Node.js
• google-protobuf: Protocol Buffers library for Node.js
• grpc-tools: Tools for compiling .proto files
• mongodb: MongoDB driver for Node.js

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License

ISC

Author

Alejandro Mariscal Romero