geojson-validator 0.4.0

Validates and fixes GeoJSON

Validate and automatically fix invalid GeoJSON. 🌎 Webapp and 🐍 Python package.

The only tool that reliably addresses all issues:

• Detects invalid geometries (GeoJSON specification): duplicate nodes, wrong winding order, ...
• Detects problematic geometries (for some tools & APIs): self-intersection, crossing anti-meridian, ...
• Checks against GeoJSON schema if all required JSON elements exist
• Automatically fixes invalid geometry issues

🎈 Try it out: geojson-validator webapp 🎈

Quickstart

# Installation
pip install geojson-validator

See the three main functions below. Data input can be any type of GeoJSON dictionary, a filepath/url to a GeoJSON, shapely geometries and anything with a __geo_interface__ (e.g. Geopandas GeoDataFrame).

import geojson_validator

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

geojson_validator.validate_schema(geojson_input)

geojson_validator.validate_geometries(geojson_input)

geojson_validator.fix_geometries(geojson_input)

1. Validate GeoJSON schema 📚

Checks the structure & formatting of the GeoJSON, e.g. if all required elements exist.

errors = geojson_validator.validate_schema(geojson_input)

If the input conforms to the GeoJSON schema returns an empty list, otherwise all the reasons and respective line/feature position where it is invalid: e.g. {"Missing 'type'": {"lines": [4], "features": [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.

result = geojson_validator.validate_geometries(geojson_input)

The result gives the reason and positional indices of the invalid geometries e.g. [0, 3]. It also shows which of the sub-geometries within a MultiType geometry make it invalid e.g. {2:[0, 5]}.

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

You can choose to validate only selected criteria, by default all are checked.

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

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

geojson_validator.validate_geometries(geojson, criteria_invalid, criteria_problematic)

3. Fix GeoJSON geometries 🟩

Fixes 6 of the most common categories of invalid geometries. All other criteria can not be fixed in a programmatic way, they require user decisions (e.g. which part of a self-intersecting geometry should be dropped). More helper-functions for this coming soon!

# Fixes "unclosed", "duplicate_nodes", "exterior_not_ccw", "interior_not_cw"
fixed_fc = geojson_validator.fix_geometries(geojson_input)

The result is a FeatureCollection with the fixed geometries. The check_crs parameter is False by default, the test is optional.

TODO

• additional reasons invalidaity
• advanced fix (e.g. coordinate preicisoon)

High:

• Improve app & gif.
  • jsondecode
  • Map?
  • Checkboxes?
  • Options?
  • just one button for validation.
  • What was fixed & validate after again.
  • https://geojson.yanzi.dev/
  • infos re file

Medium:

• more fixes?

• fc bbox order, feature bbox, geometry bbox order and other criteria

• Low:

  • Multihtreading?
  • versioning?
  • fastapi as connector, not hosted just in package for others to run.

Notes:

• Does not require a feature id, and it doesnt need to be unique

Don't:

• jsondecodeerror