Update Dockerfile

Dockerfile

@@ -1,18 +1,24 @@
 FROM python:3.10-slim
 
+# Set working directory
 WORKDIR /app
 
-# System dependencies for Postgres & builds
-RUN apt-get update \
- && apt-get install -y gcc libpq-dev --no-install-recommends \
- && rm -rf /var/lib/apt/lists/*
+# Install dependencies (including PostgreSQL client for pg_isready)
+RUN apt-get update && apt-get install -y \
+    gcc \
+    libpq-dev \
+    postgresql-client \
+    --no-install-recommends && \
+    rm -rf /var/lib/apt/lists/*
 
-# Python dependencies
+# Copy requirements first to leverage Docker caching
 COPY requirements.txt .
+
+# Install Python dependencies
 RUN pip install --no-cache-dir -r requirements.txt
 
-# Copy application code
+# Copy the full application code
 COPY . .
 
-# Expose Flask port
-EXPOSE 3000
+# Default command (or override via docker-compose)
+CMD ["sh", "-c", "until pg_isready -h db -p 5432; do echo '[web] waiting for db…'; sleep 1; done && python app.py"]