Python Monorepo Example

A Python monorepo example demonstrating LangGraph agents with shared packages, similar to the JavaScript version in ../isaac-js-graph.

Structure

python-monorepo-example/
├── libs/
│   ├── shared/                 # Real package with pyproject.toml
│   │   ├── pyproject.toml
│   │   └── src/shared/
│   │       ├── __init__.py
│   │       └── utils.py        # get_dummy_message(), get_shared_timestamp()
│   └── common/                 # Faux package (no pyproject.toml)
│       ├── __init__.py
│       └── helpers.py          # get_common_prefix()
├── apps/
│   ├── agent1/
│   │   ├── langgraph.json      # deps: ["../../libs/shared", "../../libs/common"]
│   │   ├── pyproject.toml
│   │   └── src/agent1/
│   │       ├── __init__.py
│   │       ├── state.py
│   │       └── graph.py        # Simple single-node LangGraph
│   └── agent2/
│       ├── langgraph.json      # deps: ["../../libs/shared", "../../libs/common"]
│       ├── pyproject.toml
│       └── src/agent2/
│           ├── __init__.py
│           ├── state.py
│           └── graph.py        # Simple single-node LangGraph
├── pyproject.toml              # Root project with shared dependencies
├── .gitignore
└── README.md

Key Features

Shared Packages

• libs/shared/: Real Python package with pyproject.toml, containing utility functions
• libs/common/: Faux package (directory with Python files, no pyproject.toml)

Agent Configuration

• Each agent has langgraph.json with "dependencies": ["../../libs/shared", "../../libs/common"]
• This mirrors the JS monorepo pattern where shared packages are referenced via configuration rather than individual package dependencies
• Each agent has its own pyproject.toml for LangGraph-specific dependencies

LangGraph Implementation

• Simple single-node graphs that demonstrate importing from both shared packages
• Each agent outputs: "[COMMON] Agent1/2 says: Hello from shared library! (timestamp)"
• Follows the same pattern as the JS example but using Python/LangGraph

Dependencies

The root pyproject.toml contains shared dependencies:

• langgraph>=0.6.0,<0.7.0
• langchain-core>=0.2.14

Each agent's langgraph.json specifies the shared package dependencies using relative paths, allowing the LangGraph CLI to properly resolve the imports.

Usage

Each agent can be run independently using the LangGraph CLI, and both will have access to the shared utility functions via the dependency configuration.

Agent 1

langgraph build -t python-monorepo-agent-1 -c apps/agent1/langgraph.json
langgraph up -c apps/agent1/langgraph.json --image IMAGE_ID_GENERATED_ABOVE

Agent 2

langgraph build -t python-monorepo-agent-2 -c apps/agent2/langgraph.json
langgraph up -c apps/agent2/langgraph.json --image IMAGE_ID_GENERATED_ABOVE