D2 ComponentDiagram Spec¶

Source: d2.component-diagram.json

This schema describes the ComponentDiagram spec for the D2 backend.

Properties¶

Properties

Field	Type	Description
`type(required)`	`string`	Type of the diagram. Must be exactly `ComponentDiagram`.
`title`	`string` \| `null`	Optional diagram title.
`elements`	`array[Element]`	Top-level elements.
`boundaries`	`array[Boundary]`	Top-level boundaries.
`relationships`	`array[D2RelationshipSchema]`	Top-level relationships.
`render_options`	`D2RenderOptionsSchema`	D2-specific render options.
`backend(required)`	`string`	JSON schema backend. Must be exactly `d2`.

Examples

MinimalAdvanced

JSON source

{
  "backend": "d2",
  "type": "ComponentDiagram",
  "title": "Checkout API - Component Diagram",
  "elements": [
    {
      "type": "Component",
      "label": "Checkout Controller",
      "alias": "checkout_controller",
      "description": "Receives checkout requests and orchestrates payment flow.",
      "technology": "FastAPI"
    },
    {
      "type": "Component",
      "label": "Payment Service",
      "alias": "payment_service",
      "description": "Creates payment intents and handles payment state updates.",
      "technology": "Python"
    },
    {
      "type": "ComponentDb",
      "label": "Payment Store",
      "alias": "payment_store",
      "description": "Stores payment records and statuses.",
      "technology": "PostgreSQL"
    },
    {
      "type": "ComponentExt",
      "label": "Payment Gateway API",
      "alias": "payment_gateway_api",
      "description": "External API for payment authorization and capture.",
      "technology": "REST API"
    }
  ],
  "relationships": [
    {
      "type": "REL",
      "from": "checkout_controller",
      "to": "payment_service",
      "label": "Calls",
      "technology": "Python call"
    },
    {
      "type": "REL",
      "from": "payment_service",
      "to": "payment_store",
      "label": "Reads and writes",
      "technology": "SQL"
    },
    {
      "type": "REL",
      "from": "payment_service",
      "to": "payment_gateway_api",
      "label": "Creates payments via",
      "technology": "HTTPS/JSON"
    }
  ]
}

Rendered D2 source

direction: right
__title: ||md
  # Checkout API - Component Diagram
|| {
  near: top-center
}
classes: {
  c4_external: {
    style.fill: "#f7f7f7"
    style.stroke: "#767676"
    style.stroke-dash: "5"
  }
  c4_database: {
    style.fill: "#edf7ff"
    style.stroke: "#2d6f9f"
  }
}
checkout_controller: ||md
  ## Checkout Controller

  [Component: FastAPI]

  Receives checkout requests and orchestrates payment flow.
|| {
  shape: rectangle
}
payment_service: ||md
  ## Payment Service

  [Component: Python]

  Creates payment intents and handles payment state updates.
|| {
  shape: rectangle
}
payment_store: ||md
  ## Payment Store

  [Component: PostgreSQL]

  Stores payment records and statuses.
|| {
  shape: cylinder
  class: ["c4_database"]
}
payment_gateway_api: ||md
  ## Payment Gateway API

  [Component: REST API]

  External API for payment authorization and capture.
|| {
  shape: rectangle
  class: ["c4_external"]
}
checkout_controller -> payment_service: "Calls\n[Python call]"
payment_service -> payment_store: "Reads and writes\n[SQL]"
payment_service -> payment_gateway_api: "Creates payments via\n[HTTPS/JSON]"

Rendered image

JSON source

{
  "backend": "d2",
  "type": "ComponentDiagram",
  "title": "Order Processing API - Component Diagram",
  "elements": [
    {
      "type": "Component",
      "label": "Order Controller",
      "alias": "order_controller",
      "description": "HTTP entrypoint for order submission and status queries.",
      "technology": "FastAPI",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "FastAPI"
          ]
        ]
      }
    },
    {
      "type": "Component",
      "label": "Order Application Service",
      "alias": "order_app_service",
      "description": "Coordinates validation, payment, and order creation.",
      "technology": "Python",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "Python"
          ]
        ]
      }
    },
    {
      "type": "Component",
      "label": "Inventory Checker",
      "alias": "inventory_checker",
      "description": "Verifies stock availability before an order is confirmed.",
      "technology": "Python",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "Python"
          ]
        ]
      }
    },
    {
      "type": "Component",
      "label": "Payment Adapter",
      "alias": "payment_adapter",
      "description": "Wraps external payment provider calls.",
      "technology": "Python",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "Python"
          ]
        ]
      }
    },
    {
      "type": "ComponentDb",
      "label": "Order Database",
      "alias": "order_db",
      "description": "Stores orders, line items, and order status history.",
      "technology": "PostgreSQL",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "PostgreSQL"
          ]
        ]
      }
    },
    {
      "type": "ComponentExt",
      "label": "Payment Gateway API",
      "alias": "payment_gateway_api",
      "description": "External provider API for payment authorization and capture.",
      "technology": "REST API",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "REST API"
          ]
        ]
      }
    },
    {
      "type": "ComponentQueue",
      "label": "Order Events Bus",
      "alias": "order_events_bus",
      "description": "Publishes order-created and order-paid events.",
      "technology": "Kafka",
      "properties": {
        "properties": [
          [
            "Owner",
            "Checkout Team"
          ],
          [
            "Runtime",
            "Kafka"
          ]
        ]
      }
    }
  ],
  "relationships": [
    {
      "type": "REL",
      "from": "order_controller",
      "to": "order_app_service",
      "label": "Invokes",
      "technology": "Python call"
    },
    {
      "type": "REL",
      "from": "order_app_service",
      "to": "inventory_checker",
      "label": "Checks stock via",
      "technology": "Python call"
    },
    {
      "type": "REL",
      "from": "order_app_service",
      "to": "payment_adapter",
      "label": "Requests payment through",
      "technology": "Python call"
    },
    {
      "type": "REL",
      "from": "payment_adapter",
      "to": "payment_gateway_api",
      "label": "Authorizes payment via",
      "technology": "HTTPS/JSON"
    },
    {
      "type": "REL",
      "from": "order_app_service",
      "to": "order_db",
      "label": "Reads and writes",
      "technology": "SQL"
    },
    {
      "type": "REL",
      "from": "order_app_service",
      "to": "order_events_bus",
      "label": "Publishes events to",
      "technology": "Kafka"
    }
  ],
  "render_options": {
    "layout": "dagre",
    "include_properties": true,
    "bidirectional_relationships": "single_edge"
  }
}

Rendered D2 source

direction: right
__title: ||md
  # Order Processing API - Component Diagram
|| {
  near: top-center
}
classes: {
  c4_external: {
    style.fill: "#f7f7f7"
    style.stroke: "#767676"
    style.stroke-dash: "5"
  }
  c4_database: {
    style.fill: "#edf7ff"
    style.stroke: "#2d6f9f"
  }
  c4_queue: {
    style.fill: "#fff6e5"
    style.stroke: "#9b6500"
  }
}
order_controller: ||md
  ## Order Controller

  [Component: FastAPI]

  HTTP entrypoint for order submission and status queries.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | FastAPI |
|| {
  shape: rectangle
}
order_app_service: ||md
  ## Order Application Service

  [Component: Python]

  Coordinates validation, payment, and order creation.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | Python |
|| {
  shape: rectangle
}
inventory_checker: ||md
  ## Inventory Checker

  [Component: Python]

  Verifies stock availability before an order is confirmed.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | Python |
|| {
  shape: rectangle
}
payment_adapter: ||md
  ## Payment Adapter

  [Component: Python]

  Wraps external payment provider calls.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | Python |
|| {
  shape: rectangle
}
order_db: ||md
  ## Order Database

  [Component: PostgreSQL]

  Stores orders, line items, and order status history.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | PostgreSQL |
|| {
  shape: cylinder
  class: ["c4_database"]
}
payment_gateway_api: ||md
  ## Payment Gateway API

  [Component: REST API]

  External provider API for payment authorization and capture.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | REST API |
|| {
  shape: rectangle
  class: ["c4_external"]
}
order_events_bus: ||md
  ## Order Events Bus

  [Component: Kafka]

  Publishes order-created and order-paid events.

  | Property | Value |
  | --- | --- |
  | Owner | Checkout Team |
  | Runtime | Kafka |
|| {
  shape: queue
  class: ["c4_queue"]
}
order_controller -> order_app_service: "Invokes\n[Python call]"
order_app_service -> inventory_checker: "Checks stock via\n[Python call]"
order_app_service -> payment_adapter: "Requests payment through\n[Python call]"
payment_adapter -> payment_gateway_api: "Authorizes payment via\n[HTTPS/JSON]"
order_app_service -> order_db: "Reads and writes\n[SQL]"
order_app_service -> order_events_bus: "Publishes events to\n[Kafka]"

Rendered image

Definitions¶

About labels and aliases

label is a display name for the element.

alias is a unique identifier used for referencing elements in relationships and layouts. If omitted, it is generated automatically.

You can also use label for referencing elements in relationships and layouts, but each label must be unique within the diagram.

D2ComponentBoundarySchema¶

D2 JSON schema for a generic boundary in a component diagram.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `Boundary`.
`elements`	`array[Element]`	Elements may be nested arbitrarily.
`boundaries`	`array[Boundary]`	Boundaries may be nested arbitrarily.
`relationships`	`array[D2RelationshipSchema]`	Relationships declared inside the boundary.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentContainerBoundarySchema¶

D2 JSON schema for a container boundary in a component diagram.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerBoundary`.
`elements`	`array[Element]`	Elements may be nested arbitrarily.
`boundaries`	`array[Boundary]`	Boundaries may be nested arbitrarily.
`relationships`	`array[D2RelationshipSchema]`	Relationships declared inside the boundary.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentDbExtSchema¶

D2 JSON schema for an external database-like component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ComponentDbExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentDbSchema¶

D2 JSON schema for a database-like component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ComponentDb`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentEnterpriseBoundarySchema¶

D2 JSON schema for an enterprise boundary in component diagrams.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `EnterpriseBoundary`.
`elements`	`array[Element]`	Elements may be nested arbitrarily.
`boundaries`	`array[Boundary]`	Boundaries may be nested arbitrarily.
`relationships`	`array[D2RelationshipSchema]`	Relationships declared inside the boundary.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentExtSchema¶

D2 JSON schema for an external component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ComponentExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentQueueExtSchema¶

D2 JSON schema for an external queue-like component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ComponentQueueExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentQueueSchema¶

D2 JSON schema for a queue-like component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ComponentQueue`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentSchema¶

D2 JSON schema for a component.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `Component`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ComponentSystemBoundarySchema¶

D2 JSON schema for a system boundary in a component diagram.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemBoundary`.
`elements`	`array[Element]`	Elements may be nested arbitrarily.
`boundaries`	`array[Boundary]`	Boundaries may be nested arbitrarily.
`relationships`	`array[D2RelationshipSchema]`	Relationships declared inside the boundary.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerDbExtSchema¶

D2 JSON schema for an external database-like container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerDbExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerDbSchema¶

D2 JSON schema for a database-like container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerDb`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerExtSchema¶

D2 JSON schema for an external container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerQueueExtSchema¶

D2 JSON schema for an external queue-like container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerQueueExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerQueueSchema¶

D2 JSON schema for a queue-like container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `ContainerQueue`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2ContainerSchema¶

D2 JSON schema for a container.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `Container`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	Optional technology.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2PersonExtSchema¶

D2 JSON schema for an external person.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `PersonExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2PersonSchema¶

D2 JSON schema for a person.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `Person`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2RelationshipSchema¶

JSON schema for relationships supported by D2 C4 diagrams.

Properties

Field	Type	Description
`type(required)`	`RelationshipType`	Type of the relationship.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Additional details about the relationship.
`from(required)`	`string`	The source element alias (or unique label).
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	The label shown on the relationship edge.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`technology`	`string` \| `null`	The technology used in the communication.
`to(required)`	`string`	The destination element alias (or unique label).
`tooltip`	`string` \| `null`	Optional D2 tooltip.

RelationshipType¶

Relationship types supported by D2 C4 diagrams.

Items

Type	Description
`BI_REL`	A bidirectional relationship between two elements.
`REL`	A unidirectional relationship between two elements.

D2SystemDbExtSchema¶

D2 JSON schema for an external database-like system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemDbExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2SystemDbSchema¶

D2 JSON schema for a database-like system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemDb`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2SystemExtSchema¶

D2 JSON schema for an external software system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2SystemQueueExtSchema¶

D2 JSON schema for an external queue-like system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemQueueExt`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2SystemQueueSchema¶

D2 JSON schema for a queue-like system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `SystemQueue`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

D2SystemSchema¶

D2 JSON schema for a software system.

Properties

Field	Type	Description
`type(required)`	`string`	Discriminator identifying the element type. Must be exactly `System`.
`alias`	`string` \| `null`	Unique identifier for the element. If not provided, it is autogenerated from the label.
`classes`	`array[string]`	Optional D2 classes.
`description`	`string` \| `null`	Optional description text.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Optional D2 layout direction for a container.
`icon`	`string` \| `null`	Optional D2 icon URL.
`label(required)`	`string`	Display name for the element.
`link`	`string` \| `null`	Optional D2 link URL.
`near`	`string` \| `null`	Optional D2 near reference.
`properties`	`DiagramElementPropertiesSchema`	Optional property table metadata.
`shape`	`string` \| `null`	Optional D2 shape.
`style`	`D2StyleSchema`	Optional D2 style attributes.
`tooltip`	`string` \| `null`	Optional D2 tooltip.

DiagramElementPropertiesSchema¶

JSON schema for tabular diagram element properties.

Properties

Field	Type	Description
`header`	`array[string]`	Header columns. Default: `["Property", "Value"]`.
`properties(required)`	`array[array[string]]`	List of rows (each row is a list of string values).
`show_header`	`boolean`	Whether to display the header row. Default: `true`.

D2 Render Options¶

D2RenderOptionsSchema¶

Render options for the D2 renderer.

Properties

Field	Type	Description
`auto_number_relationships`	`boolean`	Auto Number Relationships Default: `false`.
`bidirectional_relationships`	`enum[two_edges \| single_edge]`	Bidirectional Relationships Default: `two_edges`.
`direction`	`enum[up \| down \| left \| right]` \| `null`	Direction Default: `right`.
`fully_qualified_relationships`	`boolean`	Fully Qualified Relationships Default: `true`.
`include_properties`	`boolean`	Include Properties Default: `false`.
`include_technology`	`boolean`	Include Technology Default: `true`.
`include_type_label`	`boolean`	Include Type Label Default: `true`.
`layout`	`enum[dagre \| elk]`	Layout Default: `dagre`.
`legend`	`D2LegendSchema`
`sequence_diagram`	`boolean`	Sequence Diagram Default: `false`.
`theme`	`integer` \| `null`	Theme
`title_near`	`enum[top-left \| top-center \| top-right \| center-left \| center-right \| bottom-left \| bottom-center \| bottom-right]` \| `null`	Title Near Default: `top-center`.

D2StyleSchema¶

D2 style attributes used by D2 render options.

Properties

Field	Type	Description
`animated`	`boolean` \| `null`	Animated
`bold`	`boolean` \| `null`	Bold
`border_radius`	`integer` \| `null`	Border Radius
`double_border`	`boolean` \| `null`	Double Border
`fill`	`string` \| `null`	Fill
`fill_pattern`	`string` \| `null`	Fill Pattern
`font`	`string` \| `null`	Font
`font_color`	`string` \| `null`	Font Color
`font_size`	`integer` \| `null`	Font Size
`italic`	`boolean` \| `null`	Italic
`multiple`	`boolean` \| `null`	Multiple
`opacity`	`number` \| `null`	Opacity
`shadow`	`boolean` \| `null`	Shadow
`stroke`	`string` \| `null`	Stroke
`stroke_dash`	`integer` \| `null`	Stroke Dash
`stroke_width`	`integer` \| `null`	Stroke Width
`text_transform`	`string` \| `null`	Text Transform
`three_d`	`boolean` \| `null`	Three D
`underline`	`boolean` \| `null`	Underline

D2LegendSchema¶

Structured D2 legend render options.

Properties

Field	Type	Description
`items`	`array[D2LegendElementSchema\|D2LegendRelSchema]`	Items
`label`	`string`	Label Default: `Legend`.

D2LegendElementSchema¶

Schema for a D2 legend node sample.

Properties

Field	Type	Description
`type(required)`	`string`	Legend item discriminator. Must be exactly `element`.
`alias`	`string` \| `null`	Optional D2 identifier.
`classes`	`array[string]`	Classes
`icon`	`string` \| `null`	Icon
`label(required)`	`string`	Legend item label.
`shape`	`string` \| `null`	Shape
`style`	`D2StyleSchema`

D2LegendRelSchema¶

Schema for a D2 legend relationship sample.

Properties

Field	Type	Description
`type(required)`	`string`	Legend item discriminator. Must be exactly `relationship`.
`alias`	`string` \| `null`	Optional D2 identifier.
`bidirectional`	`boolean`	Bidirectional Default: `false`.
`classes`	`array[string]`	Classes
`hide_endpoints`	`boolean` \| `null`	Hide Endpoints
`label(required)`	`string`	Legend item label.
`source`	`string` \| `null`	Source
`style`	`D2StyleSchema`
`target`	`string` \| `null`	Target

D2 ComponentDiagram Spec¶

Properties¶

Elements¶

Boundaries¶

Relationships¶

Definitions¶

D2ComponentBoundarySchema¶

D2ComponentContainerBoundarySchema¶

D2ComponentDbExtSchema¶

D2ComponentDbSchema¶

D2ComponentEnterpriseBoundarySchema¶

D2ComponentExtSchema¶

D2ComponentQueueExtSchema¶

D2ComponentQueueSchema¶

D2ComponentSchema¶

D2ComponentSystemBoundarySchema¶

D2ContainerDbExtSchema¶

D2ContainerDbSchema¶

D2ContainerExtSchema¶

D2ContainerQueueExtSchema¶

D2ContainerQueueSchema¶

D2ContainerSchema¶

D2PersonExtSchema¶

D2PersonSchema¶

D2RelationshipSchema¶

RelationshipType¶

D2SystemDbExtSchema¶

D2SystemDbSchema¶

D2SystemExtSchema¶

D2SystemQueueExtSchema¶

D2SystemQueueSchema¶

D2SystemSchema¶

DiagramElementPropertiesSchema¶

D2 Render Options¶

D2RenderOptionsSchema¶

D2StyleSchema¶

D2LegendSchema¶

D2LegendElementSchema¶

D2LegendRelSchema¶