def flatten_geojson()

in src/mapillary/utils/format.py [0:0]

• 9 lines of code
• 6 McCabe index (conditional complexity)

def flatten_geojson(geojson: dict) -> list:
    """
    Flattens a GeoJSON dictionary to a dictionary with only the relevant keys.
    This is useful for writing to a CSV file.

    Output Structure::

        >>> {
        ...     "geometry": {
        ...         "type": "Point",
        ...         "coordinates": [71.45343, 12.523432]
        ...     },
        ...     "first_seen_at": "UNIX_TIMESTAMP",
        ...     "last_seen_at": "UNIX_TIMESTAMP",
        ...     "value": "regulatory--no-parking--g2",
        ...     "id": "FEATURE_ID",
        ...     "image_id": "IMAGE_ID"
        ... }

    :param geojson: The GeoJSON to flatten
    :type geojson: dict

    :return: A flattened GeoJSON
    :rtype: dict

    Note,
        1. The `geometry` key is always present in the output
        2. The properties are flattened to the following keys:
            - "first_seen_at"   (optional)
            - "last_seen_at"    (optional)
            - "value"           (optional)
            - "id"              (required)
            - "image_id"        (optional)
            - etc.
        3. If the 'geometry` type is `Point`, two more properties will be added:
            - "longitude"
            - "latitude"

    *TODO*: Further testing needed with different geometries, e.g., Polygon, etc.
    """

    for feature in geojson["features"]:
        # Check if the geometry is a Point
        if feature["geometry"]["type"] == "Point":
            # Add longitude and latitude properties to the feature
            feature["properties"]["longitude"] = feature["geometry"]["coordinates"][0]
            feature["properties"]["latitude"] = feature["geometry"]["coordinates"][1]

    # Return the flattened geojson
    return [
        {"geometry": _feature["geometry"], **_feature["properties"]}
        for _feature in geojson["features"]
    ]