FastAPI Setup and Run Script (Mac and Linux)

setup_run.sh

#!/bin/bash

# Get Python version
PYTHON_VERSION=$(python3 --version 2>/dev/null | awk '{print $2}')
PYTHON_MAJOR=$(echo "$PYTHON_VERSION" | cut -d. -f1)
PYTHON_MINOR=$(echo "$PYTHON_VERSION" | cut -d. -f2)

# Check if Python is at least 3.8
if [ "$PYTHON_MAJOR" -eq 3 ] && [ "$PYTHON_MINOR" -lt 8 ]; then
    echo "Python 3.8+ is required. Please install it."
    exit 1
fi

# Create virtual environment if it doesn't exist
if [ ! -d ".venv" ]; then
    echo "Creating virtual environment..."
    python3 -m venv .venv
fi

# Activate virtual environment
source .venv/bin/activate

# Install dependencies if they are missing
if [ ! -d ".venv/lib" ] || [ -z "$(pip freeze)" ]; then
    echo "Installing dependencies..."
    pip install -r requirements.txt
else
    echo "Dependencies already installed."
fi

# Detect number of CPU cores
NUM_CORES=$(nproc)

# Calculate recommended workers (2 * NUM_CORES + 1)
WORKERS=$((2 * NUM_CORES + 1))

# Prompt user for how to run FastAPI
echo "Choose how you want to run FastAPI:"
echo "1) fastapi dev (recommended for development)"
echo "2) uvicorn main:app --reload"
echo "3) uvicorn main:app with recommended workers ($WORKERS workers)"
echo "4) Set a custom number of workers (must be <= $WORKERS)"
read -p "Enter your choice (1, 2, 3, or 4): " choice

case "$choice" in
    1)
        echo "Running FastAPI using fastapi dev..."
        fastapi dev main.py
        ;;
    2)
        echo "Running FastAPI using Uvicorn..."
        uvicorn main:app --reload
        ;;
    3)
        echo "Running FastAPI using Uvicorn with $WORKERS workers..."
        uvicorn main:app --workers $WORKERS --reload
        ;;
    4)
        # Ask user for custom number of workers
        while true; do
            read -p "Enter the number of workers: " custom_workers
            if [ "$custom_workers" -le "$WORKERS" ]; then
                echo "Running FastAPI using Uvicorn with $custom_workers workers..."
                uvicorn main:app --workers "$custom_workers" --reload
                break
            else
                echo "The number of workers cannot exceed $WORKERS. Please enter a valid number."
            fi
        done
        ;;
    *)
        echo "Invalid choice. Exiting."
        exit 1
        ;;
esac