TWb Viewer for DSH · Tableau Workbook Inspector

A delivery tool for Tableau consultants. Inspect a workbook (.twb) inside DeepSeek Harness — no Tableau Desktop, no license, no data: a 1:1 SVG dashboard layout you can hand to a client as a whiteboard file, a table-level data model showing how the tables are joined, a field-level lineage graph, and the custom SQL behind each datasource. Everything is parsed in your browser; a DeepSeek Harness (DSH) plugin that reads metadata only and never touches your data.

中文 · English

What problem it solves

Workbooks are the hardest thing to explain about a Tableau deployment. You have a .twb file — from a client, a colleague, or your own archive — and you need to answer questions like:

• What is actually in this dashboard? Which worksheets sit where, how big are they, what is a container vs. a worksheet vs. a text zone.
• How do these calculated fields connect? Which field feeds which, what breaks if I change a formula, where a field's lineage starts and ends.
• How are the tables joined? A table-level data model: which table joins which, the ON condition, the join type, and the cardinality when Tableau records it.
• What SQL is behind this datasource? Every custom SQL (<relation type='text'>) pulled out and listed, so you can confirm the query logic line by line instead of opening Tableau.
• What is this workbook wired to? Server, database, file path, field roles and data types — without opening Tableau.
• How do I document it for a client? A layout you can export to Excalidraw/SVG and annotate, plus a lineage diagram you can walk through in a meeting.

Tableau Desktop shows you this by opening the workbook; DSH's plugin shows it in the browser, instantly, with no license and no data.

Features

• ✅ English & Chinese UI: the panel follows the DSH interface language (switch it in Settings → General → Language); dates, numbers and workbook data stay untouched.
• ✅ One click from the left sidebar: the plugin registers its own panel row in the DSH sidebar, so it opens as a full page next to your conversation — no digging through Settings.
• ✅ Open and it is already there: the plugin auto-loads a built-in sample workbook, so you see the whole UI in one second — then drop in your own .twb to replace it.
• ✅ 1:1 dashboard layout: every dashboard zone is drawn as SVG at true scale (worksheets, containers, text), with zoom / pan and one-click export to SVG / PNG / Excalidraw for annotated review decks.
• ✅ Table-level data model: every datasource's relation tree is parsed into tables + joins — join type (inner/left/right/full), the ON expression, and cardinality when the file records it — drawn as an arc diagram (balanced curves, children centred on their parent) with a detail pane.
• ✅ Parameters, read properly: Tableau parameters get their own tab, with the current value formatted by the workbook's own number format (p0.00% → 6.40%, C2052 → ¥50,000) instead of the raw float64 stored in the file (0.064000000000000001); the raw value stays visible for verification.
• ✅ Custom SQL inventory: each <relation type='text'> is extracted, listed per datasource and copyable, so agreeing on the query logic takes one screen instead of a Tableau session.
• ✅ Zone-level detail: zone subtypes (worksheet / flow container / basic container / card such as filters and titles / text / empty) are colour-coded with a legend, and hovering a zone shows its size, padding, margin and fill.
• ✅ Field lineage graph: layered dependency graph — datasource → raw fields → calculated fields. Click any node for its upstream inputs / downstream dependents, search, and filter by role (dimension / measure / calculation).
• ✅ Built for large workbooks: above 1,200 nodes the graph auto-focuses on the selected node's ±2 hops (switchable ±1/±2/±3/all), so a 5,000-node workbook stays smooth instead of freezing the panel.
• ✅ Full-screen mode (and no accidental zooming: the lineage graph pans and fits, but no longer zooms on scroll): one click fills the browser window (Esc to exit); layout and lineage refit automatically.
• ✅ State persisted: the parsed workbook is cached (with shape validation), so switching panels or reloading the page brings back your file and current view.
• ✅ Workbook panel: the layout view's right side lists dashboards (worksheet count; click to switch) and the worksheets of the selected dashboard — click one to highlight its zones in the 1:1 layout (click again to clear). Nothing else competes for attention.
• ✅ Custom SQL in context: every custom-SQL datasource sits on the right of the data model; the first one is selected on entry, so the full query is one click (or zero) away, with a copy button and the datasource/connection it belongs to.
• ✅ Parameters as their own class: in the lineage graph parameters are a separate category (own colour, own filter) — never counted as dimensions or measures — and selecting one shows the value formatted by the workbook's own format plus the raw value.
• ✅ Read-only and private: parsing happens in the browser; the file is never uploaded. The Node half only serves a built-in sample route.

Data safety: .twb only, .twbx is refused by design

Format	What it contains	This plugin
.twb	Metadata only — XML with connection info, field definitions, calculation formulas, dashboard zone layout. No data rows.	✅ Supported
.twbx	A zip package that can embed data extracts (.hyper / .tde), images, and more	❌ Refused on purpose

Refusing .twbx is a deliberate security decision: a packaged workbook can carry your full dataset, and pulling that into an inspection flow widens the data-exposure surface for no benefit. The plugin only ever reads data-free .twb metadata. If you pick a .twbx you get an explicit message telling you to Save As → .twb in Tableau.

Screenshots

Where it lives — a panel row in the left sidebar; the viewer opens as a full page beside your conversation

Dashboard layout — 1:1 SVG rendering of every zone, with SVG / PNG / Excalidraw export

Field lineage — datasource → raw fields → calculated fields; click a node for up/downstream

Data model — tables, join types, ON conditions and cardinality (synthetic workbook; client files never leave the machine)

Parameters — current values formatted the way the workbook formats them, raw values kept for verification

Custom SQL — every custom query in one list, ready for scope confirmation

Workbook panel — dashboards and worksheets only: click a dashboard to switch, a worksheet to jump to where it is used

Install

Requires a working DSH Web setup (dsh web). Installing a plugin writes into $DSH_HOME/profiles/web and restarts with dsh web.

1. Straight from GitHub (recommended)

dsh plugin --profile web add github:tableau-China/dsh-tableau-twb-viewer

2. From a GitHub Release (version-pinned tarball)

Every release ships an installable tarball — see Releases:

dsh plugin --profile web add https://github.com/tableau-China/dsh-tableau-twb-viewer/releases/download/v0.2.0/dsh-tableau-twb-viewer-0.2.0.tgz

3. From npm

dsh plugin --profile web add dsh-tableau-twb-viewer

4. From a local checkout (development)

git clone https://github.com/tableau-China/dsh-tableau-twb-viewer.git
dsh plugin --profile web add ./dsh-tableau-twb-viewer

Restart dsh web after installing — the client plugin list is scanned at boot. Uninstall with dsh plugin --profile web remove dsh-tableau-twb-viewer.

Usage

1. Open DSH Web and click TWb Viewer in the left sidebar. The built-in sample loads automatically.
2. Replace it with your own file: click Choose .twb file or drag a .twb onto the uploader.
3. Layout tab: 1:1 dashboard rendering with a zone-type legend (worksheet / container / card / text / empty); zoom, pan, fit, hover a zone for its size and padding, and export SVG / PNG / Excalidraw.
4. Lineage tab: click any node to see upstream/downstream lineage; search and filter fields; use the Focus control to show ±1/±2/±3 hops or the whole graph.
5. Data model tab: tables, join types, ON conditions and cardinality; click a table for its datasource and physical name, or a join for its detail.
6. ⛶ Full screen for large workbooks; Esc or ✕ Exit full screen to come back.
7. The right-hand metadata panel covers datasources, fields, calculations, worksheets, and the Custom SQL inventory.

Troubleshooting

Symptom	Fix
No "TWb Viewer" row in the sidebar	Restart dsh web, then hard-refresh the browser tab (Cmd+Shift+R / Ctrl+F5) — the tab may still run the pre-install bundle.
"This is not a valid Tableau workbook"	The file must be a .twb (XML). If you only have a .twbx, open it in Tableau and Save As → .twb.
A .twbx was refused	Working as intended — see Data safety.
Very large workbook feels slow	The lineage graph already auto-focuses above 1,200 nodes; use the Focus control (±1 hop) to narrow further.

Development

npm install              # esbuild / xmldom / puppeteer-core (dev-only)
npm run build            # src/ -> lib/client.js (DSH ModuleLoader bundle)
npm run verify           # snapshot tests: parse / graph / layout / tokenizer baselines
npm run verify:update    # regenerate baselines after an intended change
npm run verify:reference # optional: byte-for-byte diff against the original implementation
npm run bench            # performance curve + O(n²) regression guard
npm run gen-css          # regenerate the scoped stylesheet from the source CSS

End-to-end test in a real browser (needs local Chrome and dsh on PATH):

./test/e2e-boot.sh 3199     # terminal A: boots an isolated DSH instance, prints a token URL
TWB_URL="http://127.0.0.1:3199/?token=..." npm run e2e   # terminal B: headless Chrome, 72 assertions

# also verify large-workbook focus behaviour
TWB_LARGE_FIELDS=1500 TWB_URL="..." npm run e2e

npm 11.16+ blocks dependency build scripts by default; package.json carries an explicit allowScripts entry for esbuild, otherwise npm install leaves esbuild without its binary.

Structure

dsh-tableau-twb-viewer/
├── package.json           # dsh.bundle (config layer) + dsh.client (web plugin declaration)
├── cordis.patch.yml       # bundle patch: inserts the plugin row
├── index.js               # Node half: serves the built-in sample route (lazy, degradable)
├── src/
│   ├── parser.js          # .twb XML parsing (dashboard zones / datasources / fields / formulas)
│   ├── graph.js           # lineage graph + layered layout + up/downstream reachability
│   ├── formula.js         # calculation formula tokenizer / highlighter
│   ├── app.jsx            # all UI components + plugin entry (settings.section)
│   ├── plugin.css         # plugin-owned styles (full screen, focus control)
│   └── style.css          # scoped app styles (.twb-root prefix, generated by gen-css.mjs)
├── build.mjs              # esbuild -> lib/client.js (ModuleLoader factory format)
├── lib/client.js          # build artifact (shipped)
└── test/                  # snapshot tests, benchmark, headless-Chrome e2e

Compatibility

DSH version	Status
0.1.0-rc.6	✅ development baseline (first release)
0.2.1-alpha.2	✅ verified end-to-end (72 assertions incl. zh/en switching, data model, custom SQL, auto-loaded sample, large-graph focus)

Install mechanisms used: dsh.bundle.patch (makes the package a loaded plugin row) and dsh.client with an exported ./client bundle (injected into the browser module graph by client-modules). The UI registers itself into the settings.section slot, and the Node half uses the webServer service for the sample route.

Author

Yupeng Wu (@tableau-China) — Tableau & data-visualisation practitioner.

License

Apache-2.0.