# Portaljs Add Chart

Add a chart (line, bar, area, pie, or scatter) to a dataset's showcase in a PortalJS...

- Repository: https://github.com/datopian/portaljs (2370 stars)
- Category: Data and ML
- License: MIT
- Last updated: 2026-10-28
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add datopian/portaljs --skill portaljs-add-chart -g -a claude-code -y`
Codex: `npx skills add datopian/portaljs --skill portaljs-add-chart -g -a codex -y`
Cursor: `npx skills add datopian/portaljs --skill portaljs-add-chart -g -a cursor -y`
Gemini CLI: `npx skills add datopian/portaljs --skill portaljs-add-chart -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add datopian/portaljs`

## Description

Add a chart (line, bar, area, pie, or scatter) to a dataset's showcase in a PortalJS portal. Installs recharts, writes a reusable Chart component, and renders it in the showcase Views section. Use when visualizing a dataset already registered in datasets.json.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# PortalJS, Add Chart

## Overview

Add a visualization to a dataset's **showcase** in a PortalJS portal. The skill installs
`recharts` (added directly, never `@portaljs/components`), writes a reusable client-side
`Chart` component into `components/`, and renders a `<Chart />` into the **Views** section
of the showcase route `pages/[owner]/[slug].tsx` for one chosen dataset. The chart reads the
same `/public/data/<file>` the showcase `<Table />` already uses, so no data is duplicated.
Five chart types are supported: line, bar, area, pie, and scatter.

## Prerequisites

- A scaffolded PortalJS portal (see `portaljs-new-portal`).
- The target dataset already registered in `datasets.json` (see `portaljs-add-dataset`).
- `components/ui/parseCsv.ts` present (ships with the template).
- Node 18+ and npm available in the portal directory.

## Instructions

The canonical, full step-by-step workflow is
[`.claude/commands/portaljs-add-chart.md`](https://github.com/datopian/portaljs/blob/main/.claude/commands/portaljs-add-chart.md), the single source of truth. Read and follow it when executing. Summary:

1. Gather input, dataset slug, X column, Y column(s), chart type (default `line`), portal
   directory. If any is missing, interview the user; never dead-end on a missing value.
2. Resolve the dataset from `datasets.json` (`namespace`, `file`, `format`).
3. Validate that the X and every Y column exist in the data file's header; warn on
   non-numeric Y columns (values are coerced with `Number()`).
4. Install the chart library: `npm install recharts@^2.15.0`.
5. Write `components/Chart.tsx` (idempotent, do not overwrite a customized component).
6. Render `<Chart />` into the Views section, gated on the dataset's `(namespace, slug)` so
   other showcases are unaffected. Extend an existing view-dispatch block, do not overwrite.
7. Verify with `npx tsc --noEmit`.
8. Report the component, route, and dependency added.

## Output

The rest: https://github.com/datopian/portaljs/blob/HEAD/skills/portaljs-add-chart/SKILL.md