Portaljs Add Dataset Skill for Claude

PortalJS — Add Dataset

Overview

Register a dataset in a PortalJS (portaljs-catalog) portal. The skill appends one entry to

datasets.json — the single source of truth for the catalog — and routes the underlying

bytes by source first, then size: a local file defaults to R2 via Git LFS, a remote URL

defaults to passthrough (no copy). No per-dataset page is created; the catalog at /search

lists the new entry and the dynamic showcase route pages/[owner]/[slug].tsx renders it

automatically at /@<namespace>/<slug>. Supported formats for the showcase preview: CSV,

TSV, JSON (array), and GeoJSON.

Prerequisites

• A scaffolded PortalJS portal (see portaljs-new-portal) with datasets.json,

package.json, and pages/[owner]/[slug].tsx present.

• The source data: a local file path or a publicly reachable URL.
• For the R2/Git LFS default route: git and git-lfs installed, and an Arc account token

(or an OSS Giftless key) to mint a push-scoped LFS credential.

• Node 18+ and npm available in the portal directory.

Instructions

The canonical, full step-by-step workflow is

.claude/commands/portaljs-add-dataset.md —

the single source of truth. Read and follow it when executing. Summary:

• Gather input from $ARGUMENTS — source (file path or URL), portal directory (default

.), dataset name/slug, description, namespace. If the source is missing, interview the

user; never dead-end.

• Validate the portal directory: confirm datasets.json, package.json, and

pages/[owner]/[slug].tsx exist.

• Detect the format from the file extension, URL extension, or Content-Type header

(CSV, TSV, JSON array, or GeoJSON); reject anything else and ask for a conversion.

• Route the data by source: remote URL → passthrough (default) or adopt into R2 (opt-in);

local file → R2 via Git LFS (default) or inline into public/data/ (fenced exception for

bundled samples or an OSS-no-R2 fallback).

• Append one entry to datasets.json — slug, namespace, name, description, file

(the routed path/URL), format — keeping (namespace, slug) unique.

• Verify the build with npx next build; fix errors (commonly malformed JSON) before

reporting success.

• Report the route taken, the manifest change, and the showcase URL.

Output

• Modified: datasets.json (one entry appended).
• Created (route-dependent): data/<slug>.<ext> tracked via Git LFS (R2 default), or

public/data/<slug>.<ext> (inline exception). Nothing is created for remote passthrough.

• Verified: npx next build passes.
• Result: the dataset appears in /search and renders at /@<namespace>/<slug>.

Error Handling

| Symptom | Cause | Fix |

| --- | --- | --- |

| Fetch fails for a URL source | Non-200 status or unreachable host | Report the HTTP status and ask the user to confirm the URL is publicly accessible. |

| "Not a portaljs-catalog portal" | datasets.json missing | This is an older single-page template; ask the user how to proceed rather than failing silently. |

| Unsupported format | Extension/content-type isn't csv/tsv/json/geojson | Ask the user to convert the source before continuing. |

| git lfs push has nothing to stream | git lfs install --local never ran, so raw bytes were committed instead of a pointer | Run git lfs install --local before git lfs track, re-add and re-commit the file. |

| R2 PUT returns 400 | A broad http.extraHeader was set and replayed onto the presigned URL | Use the _jwt Basic-auth piggyback in lfs.url only — never a global http.extraHeader. |

| (namespace, slug) clash | Another entry already uses that pair | Ask the user for a different slug or namespace. |

| next build fails | Malformed JSON in datasets.json | Print the build log, fix the JSON, rebuild before reporting success. |

Examples

Example 1 — Local CSV, default R2 route

/portaljs-add-dataset ./data/co2-emissions.csv namespace=climate

Moves the file into data/, tracks it with Git LFS, pushes it to R2, and appends a manifest

entry whose file is the resulting https://data.portaljs.com/... URL.

Example 2 — Remote URL, passthrough (no download)

/portaljs-add-dataset https://example.org/open-data/trade.csv namespace=trade

Detects the format from the response headers and records the URL as-is in datasets.json —

no bytes are copied.

Example 3 — GeoJSON adopted into R2

/portaljs-add-dataset https://example.org/boundaries.geojson namespace=reference adopt=true

Downloads the file, then routes it as a local file through the Git LFS → R2 path so it is

hosted and versioned under the portal (useful when in-browser range queries are needed).

Example 4 — Bundled sample data, inline exception

/portaljs-add-dataset ./samples/demo.csv namespace=reference

When the portal has no R2 credentials (OSS self-host) or the file is bundled sample data,

the skill copies it into public/data/ instead, per the .gitattributes inline fence.

Resources

• Full workflow: .claude/commands/portaljs-add-dataset.md
• Manifest fields and routing details: references/reference.md
• Related skills: portaljs-new-portal, portaljs-add-chart, portaljs-add-map, portaljs-define-schema
• Git LFS documentation: <https://git-lfs.com/>