Talks - Lazouich Ford: Geospatial Validations Using FastAPI and PostGIS

PostGIS is a Postgres extension that enables working with geospatial data and queries through functions like st-makepoint, st-intersects, and st-distance

FastAPI can be used to validate geospatial data through:

• Pydantic models
• Dependency injection
• Response model validation

Shapefiles consist of multiple files containing different portions of data:

• Geometry data
• Spatial reference data
• Table/attribute data

When working with geospatial data, important considerations include:

• Earth’s curvature affects distance measurements
• Different projection types have various trade-offs
• Spatial Reference IDs (SRIDs) need proper handling
• Data from different reference systems requires transformation

Common validation patterns:

• Checking if points intersect with boundaries
• Validating coordinates are within expected regions
• Transforming between coordinate systems
• Protecting against bad incoming data

Best practices:

• Use SQL files over raw shapefiles for data loading
• Validate both incoming and outgoing data
• Consider computational costs of geospatial operations
• Use geoalchemy2 for ORM integration with PostGIS

The st-transform function is crucial for converting between different coordinate systems and ensuring accurate geospatial calculations