defmodule Mobilizon.Service.Geospatial.Nominatim do @moduledoc """ [Nominatim](https://wiki.openstreetmap.org/wiki/Nominatim) backend. """ alias Mobilizon.Service.Geospatial.Provider alias Mobilizon.Addresses.Address require Logger @behaviour Provider @endpoint Application.get_env(:mobilizon, __MODULE__) |> get_in([:endpoint]) @api_key Application.get_env(:mobilizon, __MODULE__) |> get_in([:api_key]) @impl Provider @doc """ Nominatim implementation for `c:Mobilizon.Service.Geospatial.Provider.geocode/3`. """ @spec geocode(String.t(), keyword()) :: list(Address.t()) def geocode(lon, lat, options \\ []) do url = build_url(:geocode, %{lon: lon, lat: lat}, options) Logger.debug("Asking Nominatim for geocode with #{url}") with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <- HTTPoison.get(url), {:ok, body} <- Poison.decode(body) do [process_data(body)] end end @impl Provider @doc """ Nominatim implementation for `c:Mobilizon.Service.Geospatial.Provider.search/2`. """ @spec search(String.t(), keyword()) :: list(Address.t()) def search(q, options \\ []) do url = build_url(:search, %{q: q}, options) Logger.debug("Asking Nominatim for addresses with #{url}") with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <- HTTPoison.get(url), {:ok, body} <- Poison.decode(body) do body |> Enum.map(fn entry -> process_data(entry) end) |> Enum.filter(& &1) end end @spec build_url(atom(), map(), list()) :: String.t() defp build_url(method, args, options) do limit = Keyword.get(options, :limit, 10) lang = Keyword.get(options, :lang, "en") endpoint = Keyword.get(options, :endpoint, @endpoint) api_key = Keyword.get(options, :api_key, @api_key) url = case method do :search -> "#{endpoint}/search?format=jsonv2&q=#{URI.encode(args.q)}&limit=#{limit}&accept-language=#{ lang }&addressdetails=1" :geocode -> "#{endpoint}/reverse?format=jsonv2&lat=#{args.lat}&lon=#{args.lon}&addressdetails=1" end if is_nil(api_key), do: url, else: url <> "&key=#{api_key}" end @spec process_data(map()) :: Address.t() defp process_data(%{"address" => address} = body) do try do %Address{ country: Map.get(address, "country"), locality: Map.get(address, "city"), region: Map.get(address, "state"), description: description(body), floor: Map.get(address, "floor"), geom: [Map.get(body, "lon"), Map.get(body, "lat")] |> Provider.coordinates(), postal_code: Map.get(address, "postcode"), street: street_address(address), origin_id: "osm:" <> to_string(Map.get(body, "osm_id")) } rescue e in ArgumentError -> Logger.warn(inspect(e)) nil end end @spec street_address(map()) :: String.t() defp street_address(body) do road = cond do Map.has_key?(body, "road") -> Map.get(body, "road") Map.has_key?(body, "road") -> Map.get(body, "road") Map.has_key?(body, "pedestrian") -> Map.get(body, "pedestrian") true -> "" end Map.get(body, "house_number", "") <> " " <> road end @address29_classes ["amenity", "shop", "tourism", "leisure"] @address29_categories ["office"] @spec description(map()) :: String.t() defp description(body) do if !Map.has_key?(body, "display_name") do Logger.warn("Address has no display name") raise ArgumentError, message: "Address has no display_name" end description = Map.get(body, "display_name") address = Map.get(body, "address") if (Map.get(body, "category") in @address29_categories or Map.get(body, "class") in @address29_classes) and Map.has_key?(address, "address29") do Map.get(address, "address29") else description end end end