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CSA Loom — the Microsoft Fabric experience for Azure tenants where Fabric isn't yet available: lakehouses, warehouses, notebooks, semantic models, Activator rules, Data Agents, across Commercial, GCC, GCC-High, and DoD IL5

Loom Map Editor — Fabric-parity spec

Captured 2026-05-26 by catalog agent. Fabric Maps (preview, Real-Time Intelligence workload) = interactive geospatial canvas powered by Azure Maps, with vector + imagery layers sourced from Eventhouses (KQL), Lakehouses (GeoJSON / Parquet / COG), Ontology entity types, and external services. Map items are semantic visualizations — layers represent ontology entity types, not raw geometry.

UI components

Top ribbon

  • New layer — picker by source type (Kusto / Lakehouse / Ontology / Imagery / External)
  • Save · Refresh · Share
  • Map style dropdown — Road · Grayscale · Satellite · Hybrid · Night
  • Settings — center, zoom, pitch, bearing, language, view (geopolitical), renderWorldCopies
  • Style overrides — country/region · adminDistrict · adminDistrict2 · roadDetails · buildingFootprint visibility toggles

Map canvas (Azure Maps web SDK)

  • Base map (vector tiles from Azure Maps)
  • Layer stack rendered in defined z-order (imagery beneath, vector above)
  • Pan / zoom / pitch / bearing controls
  • "Zoom to fit" per layer
  • Tooltips on hover over geometries
  • Auto-refresh ticker (e.g. every 5s) for streaming layers

Explorer pane (left)

  • Fabric items tab — add Eventhouse / KQL DB / Lakehouse / Ontology as a data source
  • External sources tab — WMS, WMTS, COG URL
  • Tree of attached sources with KQL functions / lakehouse files / ontology entity types
  • Per-entity … menu → Show on map (instantiates a default layer)

Data layers pane (right)

  • Ordered list of active layers
  • Per-layer … menu: Zoom to fit · Rename · Duplicate · Filter · Delete
  • Visibility toggle, opacity slider, drag to reorder
  • Color swatch + legend (when data-driven styling is on)

Layer settings (per-layer detail)

  • Geometry type: Point · Bubble · Marker · Heatmap · Line · Polygon · 3D extrusion
  • Latitude / Longitude / Geometry column pickers (for tabular sources)
  • General settings: layer color, tooltips (which properties to show on hover), zoom-level visibility range
  • Data labels: source field, font, halo
  • Data-driven styling ("Color by"): categorical (up to 100 categories, then "Other") or numeric ramp; per-category custom colors; auto-collapsed legend after 10 items
  • Clustering (point layers; shared across duplicated layers — known limitation)
  • Refresh interval (seconds, for streaming Kusto layers)

Filter panel (per-layer)

  • Add filter → New filter → Field name
  • Categorical filter (text fields; multi-select with search box)
  • Numeric range filter (slider, min/max abbreviated for readability)
  • Boolean filter (toggle)
  • Date/time filter (start/end pickers; available only on Kusto and Ontology layers)
  • Multiple filters combined with AND logic
  • Lock filter toggle to prevent unintended changes

Imagery layer types

  • Built-in Azure Maps basemaps (Satellite, Hybrid)
  • Cloud Optimized GeoTIFF (COG) from OneLake (EPSG:3857 only; 3-band RGB or 4-band RGBA only — others rejected with error)
  • External WMS / WMTS endpoints
  • PMTiles vector tiles (note: zoom-level setting unsupported with PMTiles)

Ontology layers (preview)

  • A point/line/polygon layer that represents an ontology entity type (e.g. point=Customer, line=Route, polygon=ServiceArea)
  • Ontology defines the meaning; Map defines the visual expression
  • Reuses entity properties as styling/filter inputs
  • Inherits the ontology's display-name property for tooltips

Map item JSON definition (REST)

  • MapDetails block: center, zoom, pitch, bearing, style, showLabels, language, renderWorldCopies, view, styleOverrides
  • LayerSetting[]: id, name, sourceId, latitudeColumnName, longitudeColumnName, geometryColumnName, filters[], options (full styling config)
  • Cluster aggregation expressions: operator (+, *, max, min, all, any), mapExpression, initialValue

What Loom has

  • MapEditor in apps/fiab-console/lib/editors/phase4-editors.tsx (lines 836-863)
  • Cosmos persistence of state.geojson (raw GeoJSON text)
  • JSON validation + feature count
  • Plain textarea editor (no visual renderer at all)
  • MessageBar discloses "v2.1: GeoJSON storage only" — explicitly defers the interactive renderer to v2.x
  • Separately, GeoMapEditor in geo-editors.tsx for the geo-map item type — lists Azure Maps accounts via ARM and is a real config form, but not the same item type
  • Grade: D (Stubbed) — honest about being a storage-only stub

Gaps for parity

  1. No map canvas at all — no Azure Maps web SDK integration
  2. No layer system — single GeoJSON blob, no stacking
  3. No layer settings pane — no styling, no tooltips, no labels
  4. No data-driven styling — no Color by category / ramp
  5. No filter panel — no categorical / numeric / boolean / date filters
  6. No Kusto-backed streaming layer — cannot drive a layer from Eventhouse with auto-refresh
  7. No Lakehouse-file picker — cannot point a layer at a GeoJSON/COG/PMTiles file in OneLake
  8. No Ontology layer support — cannot bind a layer to an ontology entity type
  9. No imagery layer support — no COG, WMS, WMTS, or basemap switcher
  10. No style overrides — country/region/adminDistrict toggles missing
  11. No clustering for point layers
  12. No view/center/zoom persistence beyond what GeoJSON contains
  13. No save-as Fabric Map item — Cosmos doc isn't a real Fabric item

Backend mapping

  • Azure Maps account is a hard requirement. Loom already lists accounts via ARM in GeoMapEditor; parity needs to consume an Azure Maps subscription key + the azure-maps-control JS SDK in the React shell.
  • Streaming layer: route through existing /api/eventhouse/query to fetch KQL function results on a refresh interval; transform rows to GeoJSON client-side.
  • Lakehouse layer: use the existing OneLake proxy (/api/onelake/...) to fetch GeoJSON / COG bytes; for COG, render with the azure-maps-tile-layer plugin (requires EPSG:3857).
  • Ontology layer: depends on Ontology parity work — once entity-type instances are queryable, treat them as another KQL-style source.
  • Fabric Map item REST: POST /v1/workspaces/{ws}/items with type: "Map" and a definition.parts[] payload matching the documented MapDetails / LayerSetting schema. This is the path to a real Fabric Map item.
  • Tenant gates: "Users can use Azure Maps services" + (if outside EU/US) "Data sent to Azure Maps can be processed outside your capacity's geography" must be enabled by the tenant admin — surface as a MessageBar gate.

Required Azure resources

  • Azure Maps account (S0 or G2; Loom can list existing accounts but cannot create one without ARM contributor on the RG)
  • Azure Maps subscription key OR Azure AD authentication for the JS SDK
  • Eventhouse / KQL DB for streaming layers (already wired in FiaB)
  • Lakehouse / OneLake for static layers (already wired)
  • Fabric capacity with Users can use Azure Maps services tenant setting enabled
  • For COG / custom imagery: storage account with public-read or SAS-token access to the file

Estimated effort

5-7 sessions. The Azure Maps web SDK integration (canvas + pan/zoom/style switcher) is 1 session. Layer system + per-layer settings pane is 2 sessions. Filter panel is 1 session. Streaming Kusto layer + auto-refresh is 1 session. Ontology layer is gated behind the Ontology parity work — when that's ready, 1 more session. Imagery layers (COG, WMS) are 1 session and depend on Azure Maps SDK plugin selection.

Preview honesty: Map item is in public preview as of 2026-Q2; Ontology layers within Map are a sub-preview. Some surfaces (PMTiles zoom limitation, COG band restrictions, the exact Style Overrides UI control surface) are documented but not screenshot-exhaustive on Microsoft Learn; spec captures documented behavior and gates the rest behind preview MessageBars.