CLOUDNET DRAW

Python tool to automatically discovery Azure virtual network infrastructures and generate Draw.io visual diagrams from topology data.

Website: CloudNetDraw

Blog: Technical Deep Dive

Deploy to Azure

📌 Key Features

🔎 Azure Resource Graph integration for efficient VNet discovery
📄 Outputs .drawio files (open with draw.io / diagrams.net)
🖼️ Supports hub, spoke, subnets, peerings, and Azure service icons (NSG, UDR, Firewall, etc.)
🧠 Logic-based layout with hub-spoke architecture detection
🎯 VNet filtering by resource ID or path for focused diagrams
🔐 Multiple authentication methods (Azure CLI or Service Principal)
🔗 Integrated Azure portal hyperlinks and resource metadata
🧩 Two diagram types: HLD (VNets only) and MLD (VNets + subnets)

Quick Start Guide

1. Install CloudNet Draw

CloudNet is a PyPi package. Use uv or pip.

Option A: Using uvx (Recommended - Run without installing)

uvx cloudnetdraw --help

Option B: Using uv

uv tool install cloudnetdraw

Option C: Install via PyPI

pip install cloudnetdraw

2. Authenticate with Azure

# Option 1: Azure CLI (default)
az login

# Option 2: Service Principal (set environment variables)
export AZURE_CLIENT_ID="your-client-id"
export AZURE_CLIENT_SECRET="your-client-secret"
export AZURE_TENANT_ID="your-tenant-id"

3. Generate Your First Diagram

cloudnetdraw query
cloudnetdraw hld

4. View Results

Open the generated network_hld.drawio file with Draw.io Desktop or the web version at diagrams.net.

Installation

Prerequisites

Python 3.8+
Azure CLI (az)
Azure access to subscriptions and vnets
uv for package management (preferred over pip)
Draw.io Desktop (recommended for viewing diagrams)

Configuration

CloudNet Draw uses config.yaml for diagram styling and layout settings. Key configuration sections:

# Create a local config file for customization
cloudnetdraw init-config

# Use custom config with other commands
cloudnetdraw query --config-file config.yaml

The init-config command copies the default configuration to your current directory where you can customize diagram styling, layout parameters, and other settings.

Examples

Single Hub with Multiple Spokes

# Query specific subscription
cloudnetdraw query --subscriptions "Production-Network"

# Generate both diagram types
cloudnetdraw hld
cloudnetdraw mld

Expected Output:

network_hld.drawio - High-level view showing VNet relationships
network_mld.drawio - Detailed view including subnets and services

Interactive Mode

# Interactive subscription selection
cloudnetdraw query

# Query specific subscriptions
uv run azure-query.py query --subscriptions "Production-Network,Dev-Network"

# Generate consolidated diagrams
cloudnetdraw hld

VNet Filtering

Filter topology to focus on specific hub VNets and their directly connected spokes:

# Filter by subscription/resource-group/vnet path
cloudnetdraw query --vnets "production-sub/network-rg/hub-vnet" --verbose

# Filter by full Azure resource ID
cloudnetdraw query --vnets "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/network-rg/providers/Microsoft.Network/virtualNetworks/hub-vnet"

# Multiple VNets using path syntax
cloudnetdraw query --vnets "prod-sub/network-rg/hub-vnet-east,prod-sub/network-rg/hub-vnet-west"

# Generate diagrams from filtered topology
cloudnetdraw hld
cloudnetdraw mld

Testing

Running Tests

# Run all tests with coverage
make test

# Run specific test tiers
make unit          # Unit tests only
make integration   # Integration tests only
make coverage      # code coverage
make random        # generate and validate random topologies

Development

Make Commands

The project includes several make commands for development and testing:

# Setup and help
make setup         # Set up development environment
make help          # Show all available targets

# Generate example topologies and diagrams
make examples

# Package management and publishing
make build           # Build distribution packages
make test-publish    # Publish to TestPyPI for testing
make publish         # Publish to production PyPI
make prepare-release # Run full test suite and build for release

# Cleanup
make clean         # Clean up test artifacts
make clean-build   # Clean build artifacts (dist/, *.egg-info/)
make clean-all     # Clean everything including .venv

Utility Scripts

The utils/ directory contains development tools for generating and testing topologies:

topology-generator.py

Generate Azure network topology JSON files with configurable parameters:

cd utils
# Basic usage
python3 topology-generator.py --vnets 50 --centralization 8 --connectivity 6 --isolation 2 --output topology.json

# With advanced options
python3 topology-generator.py -v 100 -c 7 -n 5 -i 3 -o large_topology.json --seed 42 --ensure-all-edge-types

Required Parameters:

-v, --vnets - Number of VNets to generate
-c, --centralization - Hub concentration (0-10, controls hub-spoke bias)
-n, --connectivity - Peering density (0-10, controls outlier scenarios)
-i, --isolation - Disconnected VNets (0-10, controls unpeered VNets)
-o, --output - Output JSON filename

Advanced Options:

--seed - Random seed for reproducible generation
--ensure-all-edge-types - Ensure all 6 EdgeTypes are present
--spoke-to-spoke-rate - Override spoke-to-spoke connection rate (0.0-1.0)
--cross-zone-rate - Override cross-zone connection rate (0.0-1.0)
--multi-hub-rate - Override multi-hub spoke rate (0.0-1.0)
--hub-count - Override hub count (ignores centralization weight)

topology-randomizer.py

Generate and validate many topologies in parallel

cd utils
# Basic usage
python3 topology-randomizer.py --iterations 25 --vnets 100 --parallel-jobs 4

# With advanced options
python3 topology-randomizer.py -i 50 -v 200 -p 8 --seed 42 --ensure-all-edge-types

Parameters:

-i, --iterations - Number of test iterations (default: 10)
-v, --vnets - Fixed number of VNets for all iterations (default: 100)
-p, --parallel-jobs - Maximum number of parallel jobs (default: 4)
--max-centralization - Upper bound for centralization weight (default: 10)
--max-connectivity - Upper bound for connectivity weight (default: 10)
--max-isolation - Upper bound for isolation weight (default: 10)
--seed - Random seed for reproducible generation
--ensure-all-edge-types - Ensure all 6 EdgeTypes are present in generated topologies

topology-validator.py

Validates JSON topologies and generated diagrams for structural integrity:

cd utils
# Validate all files in examples directory (default behavior)
python3 topology-validator.py

# Validate specific files
python3 topology-validator.py --topology topology.json --hld topology_hld.drawio --mld topology_mld.drawio

# Validate just topology file
python3 topology-validator.py -t topology.json