Implementing a Geocoder

API

To implement a geocoder, you need to write two files: a JSON metadata file and a Python file that implements the geocode and reverse functions.

The geocode function should given a string query return a list of dictionaries of geocoding results, with each dictionary having keys title, description, x and y, example below.

[
    {
        "title": "Erottaja",
        "description": "Mannerheimintie, 00120 Helsinki, Finland",
        "x": 24.9434147,
        "y": 60.1669202,
    },
    ...
]

The reverse function should given a coordinates return a list of dictionaries of reverse geocoding results, with each dictionary having keys title, description, x and y, same as for the forward geocoding.

Tips

To download data you should always use poor.http.get or poor.http.get_json in order to use Pure's user-agent and default timeout and error handling. You might also find poor.AttrDict, a dictionary with attribute access to keys, convenient when working with JSON data.

Use ~/.local/share/harbour-pure-maps/geocoders as a local installation directory in which to place your files. Restart Pure Maps, and your geocoder should be loaded, listed and available for use. During development, consider keeping your files under the Pure Maps source tree and using the Python interpreter or a test script, e.g.

>>> import poor
>>> geocoder = poor.Geocoder("my_geocoder")
>>> geocoder.geocode("erottaja, helsinki")

and qmlscene (qmlscene qml/pure-maps.qml) for testing.