mobilizon/lib/service/geospatial/pelias.ex

145 lines
4.2 KiB
Elixir

defmodule Mobilizon.Service.Geospatial.Pelias do
@moduledoc """
[Pelias](https://pelias.io) backend.
Doesn't provide type of POI.
"""
alias Mobilizon.Addresses.Address
alias Mobilizon.Service.Geospatial.Provider
alias Mobilizon.Service.HTTP.GeospatialClient
require Logger
@behaviour Provider
@endpoint Application.get_env(:mobilizon, __MODULE__) |> get_in([:endpoint])
@impl Provider
@doc """
Pelias implementation for `c:Mobilizon.Service.Geospatial.Provider.geocode/3`.
"""
@spec geocode(number(), number(), keyword()) :: list(Address.t())
def geocode(lon, lat, options \\ []) do
:geocode
|> build_url(%{lon: lon, lat: lat}, options)
|> fetch_features
end
@impl Provider
@doc """
Pelias implementation for `c:Mobilizon.Service.Geospatial.Provider.search/2`.
"""
@spec search(String.t(), keyword()) :: list(Address.t())
def search(q, options \\ []) do
:search
|> build_url(%{q: q}, options)
|> fetch_features
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)
url =
case method do
:search ->
"#{endpoint}/v1/autocomplete?text=#{URI.encode(args.q)}&lang=#{lang}&size=#{limit}"
|> add_parameter(options, :coords)
|> add_parameter(options, :type)
:geocode ->
"#{endpoint}/v1/reverse?point.lon=#{args.lon}&point.lat=#{args.lat}"
end
add_parameter(url, options, :country_code)
end
@spec fetch_features(String.t()) :: list(Address.t())
defp fetch_features(url) do
Logger.debug("Asking pelias with #{url}")
with {:ok, %{status: 200, body: body}} <- GeospatialClient.get(url),
%{"features" => features} <- body do
process_data(features)
else
_ ->
Logger.error("Asking pelias with #{url}")
[]
end
end
defp process_data(features) do
features
|> Enum.map(fn %{
"geometry" => %{"coordinates" => coordinates},
"properties" => properties
} ->
address = process_address(properties)
%Address{address | geom: Provider.coordinates(coordinates)}
end)
end
defp process_address(properties) do
%Address{
country: Map.get(properties, "country"),
locality: Map.get(properties, "locality"),
region: Map.get(properties, "region"),
description: Map.get(properties, "name"),
postal_code: Map.get(properties, "postalcode"),
street: street_address(properties),
origin_id: "pelias:#{Map.get(properties, "id")}",
type: get_type(properties)
}
end
defp street_address(properties) do
if Map.has_key?(properties, "housenumber") do
"#{Map.get(properties, "housenumber")} #{Map.get(properties, "street")}"
else
Map.get(properties, "street")
end
end
@administrative_layers [
"neighbourhood",
"borough",
"localadmin",
"locality",
"county",
"macrocounty",
"region",
"macroregion",
"dependency"
]
@spec get_type(map()) :: String.t() | nil
defp get_type(%{"layer" => layer}) when layer in @administrative_layers, do: "administrative"
defp get_type(%{"layer" => "address"}), do: "house"
defp get_type(%{"layer" => "street"}), do: "street"
defp get_type(%{"layer" => "venue"}), do: "venue"
defp get_type(%{"layer" => _}), do: nil
@spec add_parameter(String.t(), Keyword.t(), atom()) :: String.t()
def add_parameter(url, options, key) do
value = Keyword.get(options, key)
if is_nil(value), do: url, else: do_add_parameter(url, key, value)
end
@spec do_add_parameter(String.t(), atom(), any()) :: String.t()
defp do_add_parameter(url, :coords, value),
do: "#{url}&focus.point.lat=#{value.lat}&focus.point.lon=#{value.lon}"
defp do_add_parameter(url, :type, :administrative),
do: "#{url}&layers=coarse"
defp do_add_parameter(url, :type, _type), do: url
defp do_add_parameter(url, :country_code, nil), do: url
defp do_add_parameter(url, :country_code, country_code),
do: "#{url}&boundary.country=#{country_code}"
end