Tile Map Service for .NET 8

Simple and lightweight implementation of tile server basic features for .NET 8 platform. Provides access to tiles stored in several source types and serving them using various protocols.

Demo page

Features

Supported tile sources:

Source type	EPSG:3857	EPSG:4326	Notes
Local file system	✓	✓	Each tile in separate file in Z/X/Y.ext folder structure
MBTiles (SQLite)	✓	—	MBTiles 1.3 Specification
GeoTIFF local file	✓	✓	GeoTIFF basic support with `EPSG:3857` or `EPSG:4326` source image SRS only
XYZ tile service	✓	✓	XYZ with local cache for `EPSG:3857` SRS
TMS tile service	✓	✓	TMS with local cache for `EPSG:3857` SRS
WMTS tile service	✓	✓	WMTS with local cache for `EPSG:3857` SRS
WMS service	✓	—	WMS, versions 1.1.1 and 1.3.0, cache for `EPSG:3857` SRS
PostGIS database	✓	—	Mapbox Vector Tiles from `geometry` column with `EPSG:3857` SRS only

Supported protocols (service endpoints) for serving tiles:

Endpoint	EPSG:3857	EPSG:4326	Endpoint Url	Formats	Notes
XYZ (Tiled web map)	✓	✓	`/xyz`	png, jpeg, webp, mvt	Can be REST style url (/{z}/{x}/{y}.ext) or url with parameters (&x={x}&y={y}&z={z})
TMS (Tile Map Service)	✓	✓	`/tms`	png, jpeg, webp, mvt
WMTS (Web Map Tile Service)	✓	—	`/wmts`	png, jpeg, webp, mvt	Support both `RESTful` and `KVP` `GetTile` url syntax
WMS (Web Map Service)	✓	—	`/wms`	png, jpeg, tiff (geotiff)	WMS versions `1.1.1` and `1.3.0`

Coordinate system / tile grid support: Web Mercator / Spherical Mercator / EPSG:3857, basic support for geodetic EPSG:4326.
Tile image formats: raster (PNG, JPEG, WEBP) 256×256 pixels tiles, basic support of TIFF output and PBF / MVT (vector tiles).
Local cache for tiles from external tile services sources (modified mbtiles format database file, EPSG:3857 only), with blank tiles detection support.
Configuration in JSON file.
Reading sources configuration using /api endpoint (local requests only).

Using

Microsoft.Data.Sqlite for working with SQLite database.
SkiaSharp for raster images processing.
BitMiracle.LibTiff.NET for reading source GeoTIFF files and creating output TIFF images.
Npgsql .NET data provider for PostgreSQL.
OpenLayers with OpenLayers LayerSwitcher for displaying layers.
NUnit for tests.

Configuration file

Tile sources are defined in appsettings.json configuration file.

Running framework-dependent deployment

Check if .NET 8 runtime is installed on target system:

dotnet --info

The Microsoft.AspNetCore.App 8.0.0 (or later versions) should present in list.

Run the application using command:

dotnet tms.dll

After start, it will listen on default TCP port 5000 (using in-process Kestrel web server)
and tile service with demo page will be available on http://localhost:5000/ address; to enable remote calls allow connections to this port in firewall settings.

Further improvements on Linux

Some improvements can be made for better using this application in real environment:

Install nginx and configure it as reverse proxy server for Kestrel server.
Configure application to run as a service, using systemd service manager.

TODOs

.NET10 support.
Use modern C# language features and code style.
Support for more formats (image formats, vector tiles) and coordinate systems (tile grids).
Flexible settings of tile sources.
Configuration Web API / Web UI with authentication.
WMS client in Web UI.
Compare with reference implementations (servers and clients).
Using metatiles for better tiles quality.
Include test dataset(s) created from free data.
Extended diagnostics, error handling and logging.
Performance tests.
Live demo.