Chart Nodes

Chart nodes render visualizations on canvas, receiving data from connected query nodes.

What Chart Nodes Do

A chart node contains a DataGlass chart configuration. When connected to a query node via canvas edge, the chart renders with the query's data.

Creating a Chart Node

Add a text node with dgExtension to your canvas:

{
  "id": "chart-bar",
  "type": "text",
  "text": "```dg\ndata:\n  upstream: true\ntype: bar\nx: region\ny: revenue\n```",
  "dgExtension": {
    "nodeType": "chart",
    "chartConfig": "data:\n  upstream: true\ntype: bar\nx: region\ny: revenue"
  },
  "x": 400,
  "y": 0,
  "width": 500,
  "height": 400
}

Upstream Data

Charts receive data from query nodes using upstream: true:

data:
  upstream: true
type: bar
x: category
y: value

The chart waits for data from the connected query node. A loading indicator appears until data arrives.

Chart Configuration

Configure charts with standard DataGlass properties:

data:
  upstream: true       # Receive from query node
type: bar              # Chart type
x: region              # X-axis column
y: revenue             # Y-axis column
color: category        # Color by column
title: Sales Report    # Chart title
width: 600             # Width in pixels
height: 400            # Height in pixels

Supported Chart Types

Type	Description
bar	Vertical bars
line	Connected points
scatter	Individual points
area	Filled line
pie	Circular segments

Connecting to Query Nodes

Draw a canvas edge from a query node to the chart node:

[Query Node] ──edge──> [Chart Node]

The edge direction matters: data flows from source to target.

Sizing Charts

Resize chart nodes by dragging canvas handles. The chart re-renders to fit the new dimensions.

For precise control, set dimensions in the config:

width: 800
height: 600

Troubleshooting

Problem	Cause	Solution
"No data source"	Missing upstream config	Add data: { upstream: true }
"Waiting for data" timeout	No connected query	Draw edge from query node
Wrong columns	Column mismatch	Check query output columns
Chart blank	Data empty	Verify query loads data