drawn-cli 0.1.0

A minimalistic CLI tool for diagrams-as-code

Drawn

Drawn is a really minimalistic and lightweight CLI tool for diagrams-as-code – It helps users generate beautiful system diagrams using a super simple notation.

Example

From this simple code:

Sun --> Evaporation
Evaporation -(condensation)-> Clouds
Clouds -(precipitation)-> Rain
Rain --> Rivers
Rivers --> Oceans
Oceans -(evaporation)-> Evaporation

To this diagram:

Table of Contents:

• Features
• Philosophy
• Quick Start
• Configuration
• Testing
• Advanced Configuration

Features

• Simple arrow syntax - A --> B --> C
• Multi-line support - Handle complex flows
• Branching flows - One node to multiple destinations
• Professional output - High-quality SVG/PNG via Graphviz
• Fast rendering - Instant feedback
• Test coverage - Reliable and maintainable
• Inline configuration - Simple directives using % prefix

Philosophy

• Simple over complex - Minimal syntax that anyone can learn
• Fast feedback - From idea to diagram in 30 seconds
• Git-friendly - Text-based diagrams that version well
• Opinionated - Simple and consistent styling
• Advanced configuration - Customise every aspect of the diagram if required.

Quick Start

Installation

Prerequisites

Drawn requires Graphviz to be installed on your system:

# macOS
brew install graphviz

# Ubuntu/Debian
sudo apt-get install graphviz

# Windows
# Download and install from: https://graphviz.org/download/

Install from PyPI (Recommended)

# Install the latest stable version
pip install drawn-cli

# Create your first diagram
echo "API --> Server --> DB" > flow.drawn
drawn flow.drawn

Install from Source

# Clone the repo
git clone [e-mail]:parthivrmenon/drawn.git
cd drawn

# Install the package
pip install .

Development Installation

# Clone the repo for development
git clone [e-mail]:parthivrmenon/drawn.git
cd drawn

# Install dependencies (optional, for full package install)
pip install -e .

# Or run directly without installation
python drawn/cli.py flow.drawn

Usage

# Basic usage
echo "API --> Server --> DB" > flow.drawn
drawn flow.drawn

Configuration

You can configure your diagrams using simple directives with a % prefix:

Basic Configuration

% output_file: filename      # Output filename (default: flow)
% output_format: svg|png|pdf # Output format (default: svg)
% comment: My Diagram        # Title for the diagram (default: Flow)

For advanced configuration options, see Advanced Configuration.

Themes

Drawn supports three built-in themes that control the visual styling of your diagrams:

% theme: light    # Black on white (default)
% theme: dark     # White on black  
% theme: matrix   # Bright green terminal aesthetic

Examples

Light Theme Clean, professional diagrams	Dark Theme High contrast on dark background	Matrix Theme Terminal-style hacker aesthetic

Available Themes:

• light - Black text on white background (default)
• dark - White text on black background
• matrix - Bright green text on black background with terminal styling

Testing

{{ ... }}

Run all tests

python -m pytest tests/

Run tests with verbose output

python -m pytest tests/ -v

Advanced Configuration

Graph Attributes

% graph_bgcolor: transparent  # Background color (default: transparent)
% graph_dpi: 300             # Resolution in DPI (default: 300)
% graph_rankdir: TB          # Direction: TB (top-bottom), LR (left-right) (default: TB)
% graph_splines: ortho       # Line style: ortho, curved, etc. (default: ortho)
% graph_pad: 0.2             # Padding around the graph (default: 0.2)
% graph_nodesep: 1           # Horizontal separation between nodes (default: 1)
% graph_ranksep: 0.8         # Vertical separation between nodes (default: 0.8)

Node Attributes

% node_fontname: Courier     # Font for node labels (default: Courier)
% node_fontsize: 12          # Font size for node labels (default: 12)
% node_fontcolor: white      # Font color for node labels (default: white)
% node_shape: box            # Node shape: box, circle, ellipse, etc. (default: box)
% node_style: filled         # Node style: filled, dashed, etc. (default: filled)
% node_fillcolor: transparent # Fill color for nodes (default: transparent)
% node_color: white          # Border color for nodes (default: white)
% node_margin: 0.15,0.1      # Margin inside nodes (default: 0.15,0.1)

Edge Attributes

% edge_fontname: Courier     # Font for edge labels (default: Courier)
% edge_fontsize: 12          # Font size for edge labels (default: 12)
% edge_fontcolor: white      # Font color for edge labels (default: white)
% edge_color: white          # Edge line color (default: white)
% edge_arrowhead: normal     # Arrow style: normal, vee, dot, etc. (default: normal)
% edge_penwidth: 0.8         # Edge line thickness (default: 0.8)

Auto-Shapes

Drawn automatically selects appropriate node shapes based on node names to improve diagram readability:

% auto_shapes: true     # Enable automatic shape selection (default: true)
% auto_shapes: false    # Disable automatic shape selection

Shape Mappings:

• Databases (db, database, sql, postgres, mysql) → cylinder
• Caches (cache, redis, memcached) → box3d
• Queues (queue, kafka, rabbitmq) → parallelogram
• Storage (storage, bucket, s3) → folder
• Components (api, service, server) → component
• Users (user, customer) → ellipse
• Default (all others) → box