domainchart

A CLI tool that takes DDD domain model definitions (JSON) and renders them as a single self-contained HTML file with a file-tree-style layout.

Features

• Visualize DDD domain models (Entity, Value Object)
• Automatically infer aggregate boundaries from model relationships
• Single HTML file output (inline CSS, no external dependencies)
• Dark mode / light mode support (prefers-color-scheme)
• Cross-runtime: works with Node.js, Deno, and Bun

Usage

# Build HTML from JSON (output to a file)
npx domainchart build domains.json -o output.html

# Output to stdout
npx domainchart build domains.json > output.html

# Print the expected input schema as JSON Schema
npx domainchart types

# Validate an input file against the schema
npx domainchart validate domains.json

With Deno:

dx domainchart build domains.json -o output.html
dx domainchart types

Commands

| Command | Description | | ----------------------- | ---------------------------------------------- | | build <input.json> | Build HTML from a JSON domain model file | | types | Print the expected input schema as JSON Schema | | validate <input.json> | Validate a JSON input file against the schema |

Options (build)

| Option | Default | Description | | --------------------- | --------- | ------------------ | | -o, --output <path> | stdout | Output file path | | --title <title> | from JSON | Override the title |

Input Format

Define models in a flat list — the tool automatically infers aggregate boundaries from property type references.

{
  "title": "EC Site Domain Model",
  "models": [
    {
      "name": "Order",
      "kind": "entity",
      "description": "Order aggregate",
      "properties": [
        { "name": "id", "type": "OrderId" },
        { "name": "items", "type": "OrderItem[]" }
      ]
    },
    {
      "name": "OrderItem",
      "kind": "entity",
      "properties": [
        { "name": "quantity", "type": "number" },
        { "name": "unitPrice", "type": "Money" }
      ]
    },
    {
      "name": "Money",
      "kind": "value_object",
      "properties": [
        { "name": "amount", "type": "number" },
        { "name": "currency", "type": "string" }
      ]
    },
    {
      "name": "OrderId",
      "kind": "value_object",
      "properties": [
        { "name": "value", "type": "string" }
      ]
    }
  ]
}

Each model has a kind (entity or value_object), while each property has a type (either a primitive name or another model's name — used to infer parent-child relationships). Wrapper notations are stripped before matching, so OrderItem[], OrderItem?, Array<OrderItem>, and Set<OrderItem> all resolve to OrderItem. Union types like Foo | Bar (including nested forms such as Array<Foo | Bar>) are supported — each member is treated as a reference.

Run npx domainchart types (or dx domainchart types) to get the full JSON Schema. See spec.md for the schema definition.

Development

# Run tests in Deno
deno test --allow-read --allow-env --allow-run
# Run tests in Node
npx deno-test

# Format
deno fmt

# Lint
deno lint

License

MIT