Library System

Description

The Library System is a Python application designed to manage a library's books, loans, and borrowers. The application uses PostgreSQL as its database backend and provides a command-line interface (CLI) to interact with the system. You can add, modify, and delete books, borrowers, and manage loans. This application also supports test environments, ensuring that the functionality is thoroughly verified.

Prerequisites

Before running the application, make sure you have PostgreSQL and Python installed and running on your system.

Installation and Setup

Clone the repository:

git clone https://github.com/m-grande/library-system.git
cd library-system

Step 1: Open psql

Open your terminal and launch psql to interact with PostgreSQL:

psql

Step 2: Create Databases

Create two local databases - one for production and one for testing:

CREATE DATABASE library_db;
CREATE DATABASE library_test_db;

Step 3: Exit psql

Once the databases have been created, exit psql by running:

\q

Step 4: Initialize Database Structure

For each database, initialize the table structures using the init.sql file:

psql -d library_db -U your_username -h localhost -f db/init.sql
psql -d library_test_db -U your_username -h localhost -f db/init.sql

Step 5: Import Sample Data

Next, import the data for authors, genres, books, and borrowers into the library_db:

psql -d library_db -U your_username -h localhost -f db/data/authors.sql
psql -d library_db -U your_username -h localhost -f db/data/genres.sql
psql -d library_db -U your_username -h localhost -f db/data/books.sql
psql -d library_db -U your_username -h localhost -f db/data/borrowers.sql

Step 6: Update Database Configuration

Modify the DATABASE_CONFIG in app/db_connection.py. Replace your_username with your PostgreSQL username:

DATABASE_CONFIG = {
    "production": {
        "dbname": "library_db",
        "user": "your_username",
        "host": "localhost",
        "port": "5432",
    },
    "test": {
        "dbname": "library_test_db",
        "user": "your_username",
        "host": "localhost",
        "port": "5432",
    }
}

Step 7: Set Up a Virtual Environment

It's recommended to run the application in a virtual environment:

1. Create a virtual environment:

   python3 -m venv venv
   

2. Activate the virtual environment:

   source venv/bin/activate
   

3. To deactivate the virtual environment, run:

   deactivate
   

Step 8: Install Dependencies

Install the required Python dependencies:

pip install -r requirements.txt

Running the Application

To run the application in the production environment, use:

ENV=production python3 -m app.cli

Running the Tests

To run the test suite, use the following command:

ENV=test pytest -v

Additional Notes

• Make sure your PostgreSQL server is running and accessible at localhost on port 5432.
• The test database (library_test_db) is used to isolate test runs from the production database.
• The CLI allows for easy management of the library, including adding books, borrowers, and managing loans.

If you encounter any issues or have questions, feel free to raise an issue or contribute to the project.