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 Enum.map(body, fn entry -> process_data(entry) end) 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 %Address{ addressCountry: Map.get(address, "country"), addressLocality: Map.get(address, "city"), addressRegion: Map.get(address, "state"), description: Map.get(body, "display_name"), floor: Map.get(address, "floor"), geom: [Map.get(body, "lon"), Map.get(body, "lat")] |> Provider.coordinates(), postalCode: Map.get(address, "postcode"), streetAddress: street_address(address) } end @spec street_address(map()) :: String.t() defp street_address(body) do if Map.has_key?(body, "house_number") do Map.get(body, "house_number") <> " " <> Map.get(body, "road") else Map.get(body, "road") end end end