Module 15 Lesson 2: Dockerizing LangChain
Isolation at Scale. How to create a Docker container for your AI app to ensure it runs everywhere from AWS to Azure.
Docker: The Portable Brain
Docker allows you to "Freeze" your entire computer—OS, Python, and Libraries—into a single Image. This is the standard way to deploy any professional web application.
1. The Dockerfile
Create a file named Dockerfile in your root directory.
# 1. Use a lightweight Python image
FROM python:3.11-slim
# 2. Set the working folder
WORKDIR /app
# 3. Copy and Install requirements
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
# 4. Copy the code
COPY . .
# 5. Run the server
CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]
2. Setting Up .dockerignore
You don't want to copy your 2GB virtual environment into the container.
Create a .dockerignore file:
venv/
.env
__pycache__/
.git/
3. Visualizing the Containerization
graph TD
App[Your App Code] --> B[Build Process]
Req[Requirements] --> B
OS[Python 3.11 Slim] --> B
B --> Image[Docker Image: 'my-agent:v1']
Image -->|Deploy| Cloud[Cloud Machine]
4. Why Docker is "Required" for AI
- Dependency Hell: Some vector stores (like Chroma) require specific C++ libraries. If you don't use Docker, the server will often crash because it's missing a specific system-level library.
- Scaling: With an image, you can spin up 10 copies of your agent in seconds.
5. Engineering Tip: Building Images
To build and run your container locally:
docker build -t my-ai-agent .docker run -p 8000:8000 --env-file .env my-ai-agent
Key Takeaways
- Docker provides a consistent environment (OS + Code + Deps).
- The Dockerfile is the blueprint for your container.
.dockerignoreprevents bloated images.- Containerization handles the system-level dependencies required by AI libraries.