A display server for geospatial data hosted as GitHub Releases assets in the following repositories:

• indian_admin_boundaries
• indian_water_features
• indian_transport
• indian_communications
• indian_facilities
• indian_cadastrals
• indian_land_features
• india_natural_disasters
• indian_buildings
• indian_power_infra
• indian_industries

GitHub Releases downloads do not enable CORS, so browser JavaScript cannot read these files directly from another site. The Cloudflare Worker exists to make that data usable in web maps: it reads the release assets and serves tiles and metadata with CORS enabled. Its viewers use a same-origin proxy for file reads. The data files remain hosted on GitHub Releases. Command-line tools such as iomaps can read them directly because they are not subject to browser CORS restrictions.

Contains code for getting tiles from a big pmtiles file which has been split into multiple shards (to overcome hosting size limits).

Tools for splitting a big pmtiles into smaller ones is at pmtiles_mosaic.

See the list of data available at https://indianopenmaps.com/

Use iomaps to extract remote GeoParquet features by polygon or bounding box and export them in other geospatial formats.

Architecture

The project has two main components: a Cloudflare Worker that serves tiles and web viewers, and a Python CLI tool (iomaps) for data extraction and filtering.

Worker (worker/)

A Hono-based Cloudflare Worker that serves vector and raster tiles from PMTiles archives and Cloud-Optimized GeoTIFFs (COGs), along with web-based map viewers.

Tile serving:

• Serves vector tiles (protobuf) and raster tiles (webp/png) from PMTiles archives
• Supports "mosaic" mode for large PMTiles files that have been split into multiple shards
• Dynamically generates tiles from north-up EPSG:3857 COG byte imagery
• Provides TileJSON metadata endpoints for each source

See Worker caching for cache policy, refresh configuration, and viewer cache migration.

STAC API:

• Implements a STAC API for browsing raster collections (e.g. SOI Open series maps 50k)
• Supports spatial, date and ID filters, with paginated search results.
• The HTTP API is optional for clients that read STAC GeoParquet: iomaps and Rustac can search the same release indexes directly on GitHub. See direct-index examples and API differences.
• EPSG:3857 COG items expose standard Web Map Links xyz links for generic viewers. See compatibility checks.

Web viewers (in worker/static/):

• Vector tile viewer using MapLibre GL JS — layer selection, feature inspection, styling, 3D terrain with altitude shown on click, geocoding, and partial data download from remote parquet sources in multiple formats using geoparquet-extractor
• Raster tile viewer for raster/COG data
• STAC viewer using Leaflet for browsing STAC collections
• COG viewer for on-demand COG visualization
• No build step — browser-native ES modules with dependencies loaded from esm.sh

Other endpoints:

• /api/routes — lists all available tile sources
• /cog-info and /cog-tiles/{z}/{x}/{y} — COG metadata and tiles

Running locally:

cd worker
npm install
npm run dev  # http://localhost:8787

To override the Protomaps browser key locally, set PROTOMAPS_API_KEY in worker/.dev.vars. This local configuration file is ignored by Git.

Run npm test from worker/ for the offline Worker tests.

Python CLI — iomaps (python/)

A Python package (available on PyPI) providing CLI tools for working with the data.

Commands:

• iomaps cli stac — discover raster collections and extract imagery by bounding box
• iomaps cli extract — extract features from remote GeoParquet by polygon or bounding box
• iomaps cli sources — list available remote data sources (with category filtering and fuzzy matching)
• iomaps cli search --bounds "77.1,28.5,77.3,28.7" — find sources covering an area
• iomaps cli source-categories — list available data categories
• iomaps ui — launch a PyQt5 GUI for remote Parquet extraction

Example usage:

pip install iomaps
iomaps cli sources                    # list available sources
iomaps cli sources -c cadastral       # filter by category
iomaps cli extract -s buildings -o buildings.gpkg -b "77.5,12.9,77.7,13.1"

See the Python documentation for installation options, Python API examples, and detailed command usage.