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🛠️ Validate GeoJSON and automatically fix invalid geometries

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GeoJSON Validator

Validate GeoJSON and automatically fix invalid geometries. Like geojsonhint, but with geometry checks & fixes!

  • 🔴 Detects invalid geometries & 🟢 fixes them : Unclosed, wrong winding order etc.
  • 🟨 Problematic geometries (for many tools & APIs): Self-intersection, crossing anti-meridian etc.
  • Checks 🧬 structure according to GeoJSON specification
  • Use Website or Python package


Quickstart Python

# Installation
pip install geojson-validator

Data input can be any type of GeoJSON object, a filepath/url, and anything with a __geo_interface__ (shapely, geopandas etc.).

import geojson_validator

geojson_input = {'type': 'FeatureCollection',
                 'features': [{'type': 'Feature', 'geometry':
                     {'type': 'Point', 'coordinates': [-59.758285, 8.367035]}}]}

geojson_validator.validate_structure(geojson_input)
geojson_validator.validate_geometries(geojson_input)
geojson_validator.fix_geometries(geojson_input)

1. Validate GeoJSON structure 🧬

Checks the structure & formatting of the GeoJSON, e.g. required elements, data & geometry types, coordinate array depth etc.

geojson_validator.validate_structure(geojson_input, check_crs=False)

Returns the reasons why the input does not conform to the GeoJSON specification. Also gives the line location and feature index to more quickly localize the issues. Example: {"Missing 'type' member": {"line": [4], "feature": [0]}.

2. Validate geometries 🟥

Checks the GeoJSON geometry objects for inconsistencies and geometric issues. See geojson-invalid-geometry for a detailed description of all invalid and problematic criteria. You can choose to validate only specific criteria, by default all are selected.

# Invalid according to the GeoJSON specification
criteria_invalid = ["unclosed", "less_three_unique_nodes", "exterior_not_ccw",
                    "interior_not_cw", "inner_and_exterior_ring_intersect"]

# Problematic with some tools & APIs
criteria_problematic = ["holes", "self_intersection", "duplicate_nodes", 
                        "excessive_coordinate_precision", "excessive_vertices", 
                        "3d_coordinates", "outside_lat_lon_boundaries", "crosses_antimeridian"]

geojson_validator.validate_geometries(geojson, criteria_invalid, criteria_problematic)

Returns the reasons (example below) and positional indices of the invalid geometries, e.g. features [0, 3]. Also indicates if a sub-geometry of a MultiType geometry make it invalid e.g. {2:[0, 5]}.

{"invalid": 
      {"unclosed": [0, 3],
       "exterior_not_ccw":  [{2:[0, 5]}],  
 "problematic":
      {"crosses_antimeridian": [1]},
 "count_geometry_types": 
      {"Polygon": 3,
       "MultiPolygon": 1}}

3. Fix GeoJSON geometries 🟩

Automatically repairs some of the most common categories of invalid geometries. Always fixes ["unclosed", "exterior_not_ccw", "interior_not_cw"]. Select additional, non-essential fixes with the parameter optional. More fixes and helper-functions (for issues that require user descisions) coming soon!

geojson_validator.fix_geometries(geojson_input, optional=["duplicate_nodes"])

The result is a GeoJSON FeatureCollection with the fixed geometries.

FAQ:

  • Why not use geojson-pydantic for the schema validation? pydantic error messages a bit convulted (if one coordinate is issing error 4 times), very schema like, not custom, not easy to understand for no nprogrammers. often would need to be translated.