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NBS Workshop

History viewer overview

The Metaweave History Viewer is a single-file HTML app (~71 KB) that browses every report a vessel has ever submitted. It’s read-only, offline, and lives next to the form in the same shared-drive folder.

History viewer voyage tab

History viewer — Voyage Reports tab.

What it does

  • Reads a history.json file from disk via the File System Access API
  • Lists every submission across four tabs: Voyage Reports, Statement of Facts, Bunker Reports, Month-End ROB
  • Filters by date range and free-text search; the Voyage tab adds NOON / ARRIVAL / DEPARTURE pill toggles
  • Clicks a row → opens a detail modal with all 90+ fields organised into seven zones, plus child tables for events, port activities, fuel breakdowns, BDN data
  • Exports the filtered set to CSV or Excel (multi-sheet SpreadsheetML)
  • Exports a single report from the detail modal to Excel or Print

What it doesn’t do

  • No editing. FSA permission is mode: 'read'. The viewer cannot modify history.json.
  • No deletion. Same reason.
  • No PDF export. Print uses the browser’s print dialog; CSV and Excel are the only file outputs.
  • No vessel comparison. It loads one history.json at a time. To compare vessels, switch the linked file via Re-link.
  • No map view. No geographic visualisation.

How it gets the data

The viewer never makes network requests. It reads the file the user selects via the File System Access API, a Chrome 86+ feature that bypasses CORS and avoids the file:// restrictions that break a normal fetch() from a local HTML page.

The selected file’s handle is persisted in IndexedDB so the viewer auto-loads the same file next time. The user can re-link a different file at any time.

See Viewing past reports for the user flow and Setting up history.json for how the file gets created.

Browser requirements

BrowserStatus
Chrome 86+✅ Supported
Edge 86+✅ Supported
Firefox❌ No File System Access API — viewer shows “Unsupported browser” gate
Safari❌ No File System Access API — viewer shows “Unsupported browser” gate

If a Master uses Firefox, the form still works (form Submit doesn’t strictly require FSA), but the local archive and the viewer don’t.

The four tabs

Voyage Reports

NOON / ARRIVAL / DEPARTURE submissions. Most-used tab. Columns: Submitted, Type, Report UTC, Vessel, Voyage, Location, Port, Lat/Lon, Events.

Statement of Facts

SOF submissions only. Columns: Submitted, Report UTC, Vessel, Voyage, Port, Activities (count).

Bunker Reports

Bunker lifts only. Columns: Submitted, Date, Vessel, Voyage, Port, BDN No, Quantity (MT).

Month-End ROB

Month-end bunker reconciliations only. Columns: Submitted, Month, Vessel, Voyage.

The viewer auto-routes each submission to the correct tab based on its reportType field — NOON / ARRIVAL / DEPARTURE go to Voyage, SOF to Statement of Facts, BUNKER to Bunker, MONTH_END_BUNKER to Month-End.

Detail modal

Clicking any row opens a full-screen modal showing the entire submission in seven labeled zones:

ZoneExamples
IdentityreportName, version, voyageNumber, vesselName, vesselCode
Position & Portlat/long, port, ETD, ice/STS/refuge flags
Vessel Statevessel condition, drafts, DWT, displacement
Distance & Main Engineobserved distance, slip, ME hours, RPM, KW
Generators & Auxiliarygen 1–4 hours/KWhrs, aux boiler, incinerator
Lub Oil & Tanksstern tube lub, ROBs, bilge, sludge
Slops & Fresh Waterslops, freshwater ROB / consumed / received

Below the zones, child tables render:

  • Event cards (NOON / ARRIVAL / DEPARTURE) — at-sea and in-port events with per-fuel consumption breakdown
  • Port Activities (SOF) — activity rows with dynamic columns
  • BDN Fuel / Biofuel (Bunker) — gsfueltypeandquantity and bdnbiofuel arrays
  • Upcoming Ports — destination + ETA

See also