# MicroService Project

This project is a TypeScript-based microservice template that uses Express.js for creating a scalable and maintainable backend service. It includes essential middleware like Helmet for security, rate limiting, and a simple logging mechanism.

## Table of Contents

- [Installation](#installation)
- [Usage](#usage)
- [Project Structure](#project-structure)
- [Configuration](#configuration)
- [Scripts](#scripts)
- [License](#license)

## Installation

To get started with this project, clone the repository and install the necessary dependencies.

```bash
git clone https://devops.ccn/PegasusCollection/Project%20Pegasus/_git/microservice
cd microservice
npm install

Usage

1. Compile the TypeScript files:

   npx tsc

2. Start the service:

   node dist/index.js

Service Class

1. Creating a Microservice:

   import { Service } from './microservice';
   
   const port = 3000; // Specify the port for your microservice
   const myService = new Service(port);

2. Adding Middleware:

   // Import middleware functions
   import {
     validateApiKey,
     validateServiceID,
     whitelist,
   } from "./microservice";
   
   // Adding middleware to the service
   myService.use(validateApiKey(["myApiKey1", "myApiKey2"])); // Add API key validation middleware
   myService.use(validateServiceID("myServiceID")); // Add service ID validation middleware
   myService.use(whitelist(["192.168.0.1", "192.168.0.2"])); // Add IP whitelist middleware

3. Adding Routes:

   // Adding a route with a handler function
   myService.addRoute("get", "/example", (req, res, logger, getService) => {
     // Handler function logic here
     res.send("Hello from the microservice!");
   });

4. Starting the Microservice:

   // Start the microservice
   myService.startServer();

Middleware Functions

1. validateApiKey:

   import { validateApiKey } from "./microservice";
   
   // Usage
   myService.use(validateApiKey(["myApiKey1", "myApiKey2"]));

2. validateServiceID:

   import { validateServiceID } from "./microservice";
   
   // Usage
   myService.use(validateServiceID("myServiceID"));

3. whitelist:

   import { whitelist } from "./microservice";
   
   // Usage
   myService.use(whitelist(["192.168.0.1", "192.168.0.2"]));

Project Structure

microservice/
├── dist/                   # Compiled JavaScript files
├── src/                    # Source files
│   ├── index.ts            # Entry point
│   ├── microservice.ts     # MicroService class definition
│   ├── db_logger.ts        # Logger utility
│   ├── db_store.ts         # Store connection utility
│   └── db_stream.ts        # Stream connection utility
├── node_modules/           # Node.js modules
├── package.json            # Project metadata and dependencies
├── tsconfig.json           # TypeScript configuration
└── README.md               # Project documentation

Configuration

The Service class requires a configuration object. This object can include various settings for your microservice. Currently, only the port setting is required.

Example of a configuration object:

const config = {
  port: 3000,
};

Scripts

The following scripts are defined in the package.json file:

• build: Compiles the TypeScript files.
• start: Runs the compiled JavaScript files.

To run these scripts, use the following commands:

npm run build
npm start

License

This project is licensed under the MIT License - see the LICENSE file for details.

This README provides usage examples for creating a microservice using the `Service` class, adding middleware, defining routes with handler functions, and starting the microservice. It also includes examples for using each middleware function individually.

This project is licensed under the MIT License.