start.sh

#!/bin/bash
set -e

# --- 1. Set Environment Variables ---
export HOME=/home/user
# DATABASE_URL, SECRET_KEY, VAPI_PUBLIC_KEY, and GROQ_API_KEY 
# must be set in Hugging Face Space Secrets.

# ChromaDB Internal Settings
export chroma_host="127.0.0.1"
export chroma_port="8080"
export chroma_collection="prepai_collection"
export CHROMA_PATH="/tmp/chroma_store"

# --- 2. Start ChromaDB (Background) ---
echo "🎨 Setting up ChromaDB..."
mkdir -p "$CHROMA_PATH"
# We use the internal 8080 port for ChromaDB
chroma run --host 0.0.0.0 --port 8080 --path "$CHROMA_PATH" &

# --- 3. Start Nginx (Non-root Mode) ---
echo "🌐 Starting Nginx..."
mkdir -p /tmp/nginx/body /tmp/nginx/proxy /tmp/nginx/fastcgi /tmp/nginx/uwsgi /tmp/nginx/scgi

cat <<EOF > /tmp/nginx.conf
worker_processes 1;
daemon off;
pid /tmp/nginx.pid;
error_log /tmp/error.log;
events { worker_connections 1024; }
http {
    include /etc/nginx/mime.types;
    default_type application/octet-stream;
    access_log /tmp/access.log;
    client_body_temp_path /tmp/nginx/body;
    proxy_temp_path       /tmp/nginx/proxy;
    fastcgi_temp_path     /tmp/nginx/fastcgi;
    uwsgi_temp_path       /tmp/nginx/uwsgi;
    scgi_temp_path        /tmp/nginx/scgi;

    server {
        listen 7860;
        server_name localhost;
        location / {
            root /usr/share/nginx/html;
            index index.html index.htm;
            try_files \$uri \$uri/ /index.html;
        }
        location /api/v1/ {
            proxy_pass http://127.0.0.1:8000/api/v1/;
            proxy_set_header Host \$host;
            proxy_set_header X-Real-IP \$remote_addr;
        }
    }
}
EOF

nginx -c /tmp/nginx.conf &

# --- 4. Wait for Services to be Ready ---
# The 502 error often happens because Backend starts before ChromaDB is listening.
echo "⏳ Waiting for ChromaDB to be responsive on port 8080..."
# Uses the built-in 'timeout' and '/dev/tcp' to check port status
timeout 30s bash -c 'until printf "" 2>>/dev/null >>/dev/tcp/127.0.0.1/8080; do sleep 1; done'

if [ $? -ne 0 ]; then
    echo "❌ Error: ChromaDB failed to start within 30 seconds."
    exit 1
fi
echo "✅ ChromaDB is ready."

# --- 5. Start Backend ---
echo "🐍 Starting Backend..."
cd Backend
# Note: Ensure your FastAPI app listens on 127.0.0.1:8000
python run.py