Sample API in Go

This repository provides a sample implementation of a RESTful API built with Go. It demonstrates a modular, clean architecture and best practices for building scalable web services. The project is ideal for developers who want to learn how to structure a Go API with proper routing, middleware, error handling, and database abstraction.

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Table of Contents

• Features
• Project Structure
• Installation
• Usage
• Endpoints
• Contributing
• License

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Features

• Clean Architecture & Modular Design:
  The code is organized into distinct directories to separate API specifications, command-line entry, handlers, middleware, and tools. This makes the codebase easier to maintain and extend.

• Routing & Middleware:
  Uses the Chi router for lightweight and flexible routing. Custom middleware handles authentication and error responses.

• Database Abstraction:
  Implements a database interface along with a mock database (mockdb) for demonstration purposes. This allows for easy swapping of database implementations without altering the business logic.

• JSON Handling & Error Responses:
  Includes examples for decoding JSON requests, encoding JSON responses, and consistent error handling using custom error handler functions.

• External Package Integration:
  Utilizes popular Go packages such as logrus for advanced logging and gorilla/schema for URL query parameter decoding.

• Generics & Modern Go Features:
  Demonstrates the usage of generics (where applicable) and modern Go features to keep the code concise and type-safe.

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Project Structure

API/
├── api
│   └── api.go                # API specifications: request/response structs and helper functions
├── cmd
│   └── api
│       └── main.go           # Application entry point: sets up the router and starts the server
├── internal
│   ├── handlers              # API endpoint handlers
│   │   ├── api.go            # Common handler functions and endpoint route definitions
│   │   └── get_coin_balance.go  # Handler for the GET /account/coins endpoint
│   ├── middleware            # Custom middleware
│   │   └── authorization.go  # Authorization middleware for endpoint protection
│   └── tools                 # Database interface and mock database implementation
│       ├── database.go       # Database interface definitions and constructor
│       └── mockdb.go         # Mock database implementation for testing/demo purposes
├── go.mod                    # Module definition
└── go.sum                    # Dependency checksums

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Installation

1. Clone the Repository:

   git clone https://github.com/RevMax-creator/sample-api-in-go.git
   cd sample-api-in-go

2. Install Dependencies:

   The repository uses Go modules. Ensure you have Go 1.18 or later installed, then run:

   go mod tidy

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Usage

1. Build & Run:

   You can run the API server using the following command:

   go run cmd/api/main.go

2. Server Details:

   The server starts on localhost:8080. You should see logs indicating that the service has started.

3. Testing the API:

   Use tools like Postman or curl to test the endpoints. For example, to get the coin balance for a user named "Alex":

   curl -X GET "http://localhost:8080/account/coins?username=alex" -H "Authorization: 123ABC"

   A successful response will include a JSON object with the coin balance and a status code.

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Endpoints

GET /account/coins

• Description:
  Returns the coin balance for a given user account.

• Parameters:

  • Query parameter username: The username of the account.
  • Header Authorization: The token required for authentication.

• Response:

  {
    "code": 200,
    "balance": 100
  }

• Error Handling:
  If the username or token is missing, or if authentication fails, the API returns an appropriate error message using standardized error responses.

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Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository.
2. Create a new branch with your feature or bugfix.
3. Commit your changes.
4. Submit a pull request describing your changes.

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License

This project is licensed under the Creative Commons Modified License. See the LICENSE file for details.

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Feel free to explore, modify, and extend this sample API to suit your needs. Happy coding!