mobilizon/lib/service/geospatial/nominatim.ex

135 lines
4.2 KiB
Elixir
Raw Normal View History

defmodule Mobilizon.Service.Geospatial.Nominatim do
@moduledoc """
[Nominatim](https://wiki.openstreetmap.org/wiki/Nominatim) backend.
"""
2019-09-22 16:26:23 +02:00
alias Mobilizon.Addresses.Address
2019-09-22 16:26:23 +02:00
alias Mobilizon.Service.Geospatial.Provider
alias Mobilizon.Config
2019-09-22 16:26:23 +02:00
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
user_agent = Keyword.get(options, :user_agent, Config.instance_user_agent())
headers = [{"User-Agent", user_agent}]
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, headers),
{: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
user_agent = Keyword.get(options, :user_agent, Config.instance_user_agent())
headers = [{"User-Agent", user_agent}]
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, headers),
{: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
2019-09-22 16:26:23 +02:00
%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
error in ArgumentError ->
Logger.warn(inspect(error))
nil
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