Expense Tracker CLI

A command-line expense tracking application written in Go that helps you manage and analyze your personal expenses.

Features

• Add expenses with description, amount, and category
• Update existing expenses
• Delete expenses
• View all expenses in a formatted list
• Get expense summaries (total and monthly)
• JSON-based persistent storage
• Concurrent-safe operations

Installation

Prerequisites

• Go 1.20 or higher
• Git

Building from Source

1. Clone the repository

git clone https://github.com/yourusername/expense-tracker.git
cd expense-tracker

2. Build the application

go build -o expense-tracker cmd/expense-tracker/main.go

3. Set the data file path

export EXPENSES_FILE_PATH=/path/to/custom/expenses.json

4. (Optional) Add to PATH

sudo mv expense-tracker /usr/local/bin/

Usage

Adding an Expense

expense-tracker add --description "Lunch" --amount 20 --category "food"
# Expense added successfully (ID: 1)

Listing All Expenses

expense-tracker list
# ID  Date       Description  Amount  Category
# 1   2024-08-06  Lunch       $20.00  food
# 2   2024-08-06  Dinner      $30.00  food

Getting a Summary

# Total summary
expense-tracker summary
# Total expenses: $50.00

# Monthly summary
expense-tracker summary --month 2024-08
# Total expenses for August: $50.00

Updating an Expense

expense-tracker update --id 1 --description "Late Lunch" --amount 25
# Expense updated successfully

Deleting an Expense

expense-tracker delete --id 1
# Expense deleted successfully

Command Reference

Add Command

expense-tracker add --description <desc> --amount <amount> [--category <category>]

• --description: Description of the expense (required)
• --amount: Amount spent (required, must be positive)
• --category: Category of expense (optional, defaults to "misc")

List Command

expense-tracker list

Shows all expenses in a tabulated format.

Update Command

expense-tracker update --id <id> [--description <desc>] [--amount <amount>] [--category <category>]

• --id: ID of the expense to update (required)
• --description: New description (optional)
• --amount: New amount (optional)
• --category: New category (optional)

Delete Command

expense-tracker delete --id <id>

• --id: ID of the expense to delete (required)

Summary Command

expense-tracker summary [--month <year>-<month>]

• --month: Month number (1-12) for monthly summary (optional)

Project Structure

.
├── cmd
│   └── expense-tracker
│       └── main.go
├── internal
│   ├── cli
│   │   └── cli.go
│   ├── models
│   │   └── expense.go
│   ├── repository
│   │   ├── interface.go
│   │   └── file
│   │       └── repository.go
│   └── service
│       └── expense_service.go
├── pkg
│   └── utils
│       └── date.go
├── go.mod
└── README.md

Data Storage

Expenses are stored in a JSON file (expenses.json) in the current directory. The file is created automatically when the first expense is added. The storage is concurrent-safe and can handle multiple operations simultaneously.

Error Handling

The application includes comprehensive error handling for:

• Invalid input values (negative amounts, invalid dates)
• Non-existent expense IDs
• File operations
• Data validation

Development

Running Tests

go test ./...

Adding New Features

1. Fork the repository
2. Create a feature branch
3. Implement your changes
4. Add tests
5. Submit a pull request

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

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

Acknowledgments

• Thanks to the Go community for the excellent standard library
• Inspired by various CLI applications and expense tracking tools