Add API Key Authentication Strategy

[Kmario19]

This pull request introduces API key authentication to secure the API. The changes include updates to the documentation, environment configuration, middleware for validation, route setup, and API documentation.

API Key Authentication:

• README.md: Added a section about API authentication, explaining the use of API keys and providing an example request.

• src/config/environment.ts: Added API_KEYS to the environment schema, making it an optional string.

• src/middleware/apiKeyValidator.ts: Created a middleware function to validate the API key from the x-api-key header against the configured keys in the environment variable.

• src/routes/index.ts: Applied the apiKeyValidator middleware to all routes to enforce API key authentication.

• swagger.json: Updated the API documentation to include the ApiKeyAuth security scheme, specifying that the API key should be included in the x-api-key header.

[Copilot]

Pull Request Overview

This pull request adds API key authentication to secure the API by introducing a new middleware, updating the environment configuration, and modifying the routes and documentation accordingly.

• Introduces middleware (apiKeyValidator) to verify the API key from requests.
• Updates the configuration to support API_KEYS and applies the middleware to all routes.
• Enhances the README to document the API key authentication process.

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

File	Description
src/routes/index.ts	Applies the new apiKeyValidator middleware to secure all routes.
src/middleware/apiKeyValidator.ts	Implements API key validation logic against the configured keys.
src/config/environment.ts	Adds API_KEYS to the environment schema as an optional string.
README.md	Updates documentation with a new section on API key authentication.

Files not reviewed (1)

• swagger.json: Language not supported

[Copilot]

Consider trimming the API keys after splitting to handle any extra spaces, e.g., change to: process.env.API_KEYS.split(',').map(key => key.trim()).

Suggested change

	const allowedKeys = process.env.API_KEYS.split(',');
	const allowedKeys = process.env.API_KEYS.split(',').map(key => key.trim());