quality: completeness: 50 accuracy: 70 reviewed: false reviewer: 'KI (Gemini)' reviewDate: null

Spatial Data Infrastructure (SDI)

The Spatial Data Infrastructure of p2d2 follows the principles of GDI-DE (Spatial Data Infrastructure Germany) and relies on open standards from the Open Geospatial Consortium (OGC).

Definition

According to the Geodata Access Act (GeoZG), a spatial data infrastructure is:

An infrastructure consisting of geodata, metadata, and geodata services, network services and technologies, agreements on shared use, access, and use, as well as coordination and monitoring mechanisms, processes, and procedures.

Architecture Components

Data Layer

• PostgreSQL/PostGIS: Spatial database
• File Storage: GeoTIFF, Shapefiles, GeoJSON

Service Layer

• GeoServer: WFS, WFS-T, WMS, WCS
• MapProxy: WMTS, TMS, Tile Caching

Presentation Layer

• p2d2 Frontend: AstroJS + OpenLayers
• QGIS: Desktop GIS for experts

OGC Standards

Web Feature Service (WFS)

• WFS 2.0: Retrieve vector geodata
• WFS-T: Transactions (Insert, Update, Delete)
• Filter Encoding: Complex queries

Web Map Service (WMS)

• WMS 1.3.0: Map display
• GetCapabilities: Service metadata
• GetMap: Map images

Web Map Tile Service (WMTS)

• WMTS 1.0.0: Pre-generated tiles
• TileMatrixSet: Tile schema
• REST/KVP: Access via REST or Key-Value-Pairs

INSPIRE Compliance

p2d2 is prepared for INSPIRE compliance:

• Metadata: ISO 19115/19119
• Data Models: INSPIRE Data Specifications
• Services: View/Download/Discovery Services

Coordinate Reference Systems

Supported CRS

• EPSG:4326: WGS 84 (Lat/Lon)
• EPSG:3857: Web Mercator (OSM)
• EPSG:25832: ETRS89 / UTM Zone 32N (Germany)
• EPSG:31466-31469: Gauss-Krüger (Legacy)

Transformation

PostGIS functions for coordinate transformation:

-- WGS84 → UTM32
SELECT ST_Transform(geom, 25832) FROM features;

-- Web Mercator → WGS84
SELECT ST_Transform(geom, 4326) FROM features;

Performance Optimization

Spatial Indices

-- GiST index for geometries
CREATE INDEX idx_features_geom ON features USING GIST(geom);

-- Analyze for query planner
ANALYZE features;

Tile Caching

• MapProxy: Pre-rendered tiles
• Cache Strategy: Seeding for frequently used areas
• Cache Invalidation: On data changes

Connection Pooling

• PgBouncer: Between GeoServer and PostgreSQL
• Pool Size: ~100 connections
• Transaction Pooling: For WFS-T

Metadata Management

GeoNetwork

# GeoNetwork as metadata catalog
docker run -d \
  --name geonetwork \
  -p 8082:8080 \
  -e POSTGRES_DB=geonetwork \
  -e POSTGRES_USER=geonetwork \
  -e POSTGRES_PASSWORD=<password> \
  geonetwork:4.2

CSW (Catalogue Service for the Web)

• CSW 2.0.2: Metadata search
• Dublin Core: Basic metadata
• ISO 19115: Geographic metadata

Monitoring

Service Health Checks

# WFS GetCapabilities
curl -s "http://geoserver:8080/geoserver/wfs?service=WFS&version=2.0.0&request=GetCapabilities"

# WMS GetCapabilities
curl -s "http://geoserver:8080/geoserver/wms?service=WMS&version=1.3.0&request=GetCapabilities"

# WMTS GetCapabilities
curl -s "http://mapproxy:8081/wmts/1.0.0/WMTSCapabilities.xml"

Performance Metrics

• Response Time: <500ms for GetMap
• Throughput: >100 req/s
• Tile Cache Hit Rate: >90%

Best Practices

• Layer Groups: Group related layers
• Styles: SLD for consistent presentation
• Caching: Aggressive caching for static data
• Security: Access control per workspace
• Monitoring: Prometheus + Grafana

::: tip INSPIRE Validator Use the INSPIRE Validator for compliance checks: https://inspire.ec.europa.eu/validator/ :::