Bar Chart

Type: bar_chart • Category: visualization

Description

Append categorical/time point to a bar chart widget

Parameters

Name	Type	Description	Required	Default
widgetId	hidden		no
pointExpr	string	Expr -> {value: number, ts?: epoch_ms, category?: str}	no
limit	number		no	500

Help

Bar Chart Worker - Categorical Data Visualization

Create bar charts for categorical or time-based data with automatic data appending and accumulation.

Data Source:

• pointExpr: Expression returning single data point: {value: number, ts?: timestamp, category?: string}
• limit: Maximum data points to retain (default: 500)

Features:

• Appending: Each execution adds new data point to existing chart
• Time-based: Optional timestamp for time-series bars
• Categorical: Optional category labels for grouping
• Accumulation: Data persists across workflow runs
• Auto-scaling: Chart automatically adjusts to data range

Data Format: Single point object with:

• value: Numeric value (required)
• ts: Timestamp in milliseconds (optional)
• category: Category/label string (optional)

Examples:

• Simple counter: pointExpr="{value: data.count}"
• Time series: pointExpr="{value: data.price, ts: data.timestamp}"
• Categorized: pointExpr="{value: data.sales, category: data.region}"

Use Cases:

• Progress tracking
• Real-time metrics
• Category comparisons
• Time-based accumulation