compare-geojson

Compare-GeoJSON

Compare functions take as inputs the following:

1. oldVersion - GeoJSON of the feature's old version
2. newVersion - GeoJSON of the feature's new version
3. callback - A function to call after processing.

Compare functions output the following:

1. error - Error if any during processing or null.
2. result - Object containing key value pairs representing findings of the compare function or an empty object.

A sample compare function would look something like this:

function checkPlaceRemoval(newVersion, oldVersion, callback) {
    var oldProps = oldVersion.properties;
    var newProps = newVersion.properties;
    var result = {};
    if (oldProps.hasOwnProperty('place') && !newProps.hasOwnProperty('place')) {
        result['result:place_removed'] = true;
    }
    return callback(null, result);
}