Exchange Rate Notifier

A Python application that monitors exchange rates (PHP/USD) and sends email notifications when rates exceed configured thresholds. The system tracks rates hourly, stores them in a PostgreSQL database, and provides daily reports with visualizations.

Features

• Hourly Rate Monitoring: Automatically fetches exchange rates and checks against upper/lower thresholds
• Email Notifications: Sends alerts when rates exceed configured thresholds
• Daily Reports: Generates and emails daily reports with exchange rate graphs
• Database Storage: Stores historical exchange rate data in PostgreSQL
• Visualization: Creates interactive charts using Plotly

Requirements

• Python 3.x
• PostgreSQL database
• OpenExchangeRates API account (free tier available)
• Email account for sending notifications

Installation

1. Clone the repository:

git clone <repository-url>
cd exchange-rate-notifier

2. Install dependencies:

pip install -r requirements.txt

3. Set up environment variables:

# OpenExchangeRates API
export OPEN_EXCHANGE_RATES_APP_ID="your_app_id"
export OPEN_EXCHANGE_RATES_APP_BACKUP_ID="your_backup_app_id"  # Optional

# PostgreSQL Database
export POSTGRES_USER="your_db_user"
export POSTGRES_PASSWORD="your_db_password"
export POSTGRES_HOST="localhost"
export POSTGRES_PORT="5432"
export POSTGRES_DBNAME="your_db_name"

# Email Configuration
export SENDER_EMAIL="your_email@gmail.com"
export SENDER_PASSWORD="your_email_password"
export RECIPIENT_EMAILS="recipient1@example.com,recipient2@example.com"

4. Set up the database: Create a PostgreSQL table named rates with the following schema:

CREATE TABLE rates (
    id SERIAL PRIMARY KEY,
    rate DECIMAL(10, 2) NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

Configuration

Edit constants.py to customize the monitored currency and thresholds:

CURRENCY = "PHP"           # Currency code to monitor
UPPER_THRESHOLD = 57.8     # Upper threshold for notifications
LOWER_THRESHOLD = 55.5     # Lower threshold for notifications

Usage

Hourly Rate Check

Run the hourly check script to fetch the current rate and send notifications if thresholds are exceeded:

python hourly.py

This script:

• Fetches the current exchange rate from OpenExchangeRates API
• Stores the rate in the database
• Checks if the rate exceeds upper or lower thresholds
• Sends email notifications if thresholds are exceeded

Daily Report

Generate and send a daily report with exchange rate visualization:

python daily.py

This script:

• Retrieves the last 24 hours of exchange rate data from the database
• Generates a line chart visualization
• Calculates average and latest rates
• Emails the report with the chart attached

Development

Code Formatting

Format code using Black and isort:

make format

Linting

Check code style:

make lint

Spell Checking

Check and fix spelling:

make spell-check
make spell-fix

Dependencies

• requests - HTTP library for API calls
• yagmail - Email sending library
• psycopg2-binary - PostgreSQL adapter
• plotly - Interactive visualization library
• kaleido - Static image export for Plotly
• keyring - Secure credential storage

License

See LICENSE file for details.