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GeoJSON Format

Description​

GeoJSON is a format for encoding geographic data structures using JSON. It's widely used for representing geographic features, their properties, and geometries. GeoJSON supports points, lines, polygons, and collections of features.

File Extensions​

  • .geojson - GeoJSON files

Implementation Details​

Reading​

The GeoJSON implementation:

  • Supports FeatureCollection (array of features)
  • Supports single Feature objects
  • Supports JSONL format (one GeoJSON object per line)
  • Converts features to dictionaries
  • Uses geojson library for validation (optional)

Writing​

Writing support:

  • Writes GeoJSON features
  • Can write FeatureCollection or individual features
  • Uses geojson library for validation (optional)

Key Features​

  • Geographic data: Designed for geographic/spatial data
  • Feature support: Handles GeoJSON Feature and FeatureCollection
  • JSONL support: Can read GeoJSON in JSONL format
  • Nested data: Supports complex geographic structures
  • Validation: Optional validation with geojson library

Usage​

from iterable import open_iterable

# Basic reading
with open_iterable('data.geojson') as source:
    for feature in source:
        print(feature)  # Each feature is a dict with geometry and properties

# Writing
with open_iterable('output.geojson', mode='w') as dest:
    feature = {
        'type': 'Feature',
        'geometry': {'type': 'Point', 'coordinates': [102.0, 0.5]},
        'properties': {'name': 'Location'}
    }
    dest.write(feature)

Parameters​

  • encoding (str): File encoding (default: utf8)

Limitations​

  1. geojson dependency: Optional but recommended for validation
  2. Memory usage: FeatureCollection format loads all features into memory
  3. Structure complexity: Complex geometries may be difficult to work with
  4. Validation: Without geojson library, no format validation

Compression Support​

GeoJSON files can be compressed with all supported codecs:

  • GZip (.geojson.gz)
  • BZip2 (.geojson.bz2)
  • LZMA (.geojson.xz)
  • LZ4 (.geojson.lz4)
  • ZIP (.geojson.zip)
  • Brotli (.geojson.br)
  • ZStandard (.geojson.zst)

Use Cases​

  • GIS data: Geographic information systems
  • Mapping: Web mapping applications
  • Spatial analysis: Geographic data analysis
  • Location data: Storing and processing location data

Error Handling​

  • Missing dependency: optional libraries raise ImportError with an install hint (pip install 'iterabledata[<extra>]' when an extra exists).
  • Write mode: read-only formats raise WriteNotSupportedError or ValueError when opened with mode="w".
  • Bad or unsupported input: may raise ValueError, OSError, or library-specific errors.
  • See Troubleshooting for decoding, detection, and engine issues.
  • JSON - Base JSON format
  • JSONL - Line-delimited JSON