Esri Map Viewer

The tool provides a focused, client-side map viewer for Esri-based geospatial data. It solves the need to quickly inspect map configurations, layers, spatial extents, and coordinate contexts without a full GIS workflow. Intended users include researchers, urban planners, students, environmental analysts, and field technicians who need to understand layer composition, basemaps, and spatial relationships during project scoping or data validation. The tool emphasizes fast rendering, scalable basemaps, and standard coordinate handling to support decision-making.
The tool integrates Esri map services through a deterministic load sequence with strict separation of required vs optional features. Required: map_config_url or preloaded map project, layer visibility control, basemap selection, coordinate reference system handling, extent display, and basic feature queries. Optional/advanced: time-enabled layers, spatial filters, search across features, on-the-fly reprojection, simple measurements (distance/area), and data export hooks. The system maintains a live view state and can produce metadata for saved configurations or shareable links. Example: a municipal planner loads a city map, toggles zoning layers, and queries parcels within a bounding box.
Inputs include map_config_url (string, optional), selected_layer_ids (array of strings, optional), crs (string, optional, e.g., EPSG:4326 or EPSG:3857), bounding_box (array of four numbers, in CRS units, optional), filters (object, optional). Outputs include view_extent (array of four numbers), center_coordinate (object with lat/lon), loaded_layers metadata, and exportables (GeoJSON, CSV, or image export). Validation: CRS must be in the supported set; layer IDs must exist in the map config. Sample: map_config_url = "https://example.com/arcgis/rest/services/Env/Map/FeatureServer".
Algorithms & Calculations: The tool resolves coordinates through supported CRS (e.g., 4326, 3857) and applies simple spatial queries against loaded feature layers. It computes bounding extents, measures distances and areas when requested, and returns feature metadata and geometry where allowed. It leverages ArcGIS REST endpoints for feature data, with client-side reprojection when necessary and basic caching for repeated views.
Error & Edge Cases: If a layer fails to load, the tool gracefully disables that layer and reports the failure in metadata without interrupting other layers. Missing map_config_url uses a default base map. Network timeouts, unsupported CRS, or oversized datasets may degrade performance and are handled by fallbacks and warnings in the API layer. Localization defaults to metric units unless specified; supports EPSG:4326 and 3857.
Assumptions & Exclusions: No data editing, transformation, or batch processing is performed; offline mode is not provided; advanced spatial analytics beyond basic queries, measurements, or exports are out of scope.