mobilizon.chapril.org-mobil.../lib/service/geospatial/photon.ex
Thomas Citharel 98b7618338
Add GeoSpatial backends for geocoding
Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Geospatial Backend

Signed-off-by: Thomas Citharel <tcit@tcit.fr>
2019-03-15 16:37:43 +01:00

88 lines
2.9 KiB
Elixir

defmodule Mobilizon.Service.Geospatial.Photon do
@moduledoc """
[Photon](https://photon.komoot.de) backend.
"""
alias Mobilizon.Service.Geospatial.Provider
require Logger
alias Mobilizon.Addresses.Address
@behaviour Provider
@endpoint Application.get_env(:mobilizon, __MODULE__) |> get_in([:endpoint])
@impl Provider
@doc """
Photon implementation for `c:Mobilizon.Service.Geospatial.Provider.geocode/3`.
Note: It seems results are quite wrong.
"""
@spec geocode(number(), number(), keyword()) :: list(Address.t())
def geocode(lon, lat, options \\ []) do
url = build_url(:geocode, %{lon: lon, lat: lat}, options)
Logger.debug("Asking photon for reverse geocoding with #{url}")
with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <-
HTTPoison.get(url),
{:ok, %{"features" => features}} <- Poison.decode(body) do
processData(features)
end
end
@impl Provider
@doc """
Photon 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 photon for addresses with #{url}")
with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <-
HTTPoison.get(url),
{:ok, %{"features" => features}} <- Poison.decode(body) do
processData(features)
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")
coords = Keyword.get(options, :coords, nil)
endpoint = Keyword.get(options, :endpoint, @endpoint)
case method do
:search ->
url = "#{endpoint}/api/?q=#{URI.encode(args.q)}&lang=#{lang}&limit=#{limit}"
if is_nil(coords), do: url, else: url <> "&lat=#{coords.lat}&lon=#{coords.lon}"
:geocode ->
"#{endpoint}/reverse?lon=#{args.lon}&lat=#{args.lat}&lang=#{lang}&limit=#{limit}"
end
end
defp processData(features) do
features
|> Enum.map(fn %{"geometry" => geometry, "properties" => properties} ->
%Address{
addressCountry: Map.get(properties, "country"),
addressLocality: Map.get(properties, "city"),
addressRegion: Map.get(properties, "state"),
description: Map.get(properties, "name") || streetAddress(properties),
floor: Map.get(properties, "floor"),
geom: Map.get(geometry, "coordinates") |> Provider.coordinates(),
postalCode: Map.get(properties, "postcode"),
streetAddress: properties |> streetAddress()
}
end)
end
defp streetAddress(properties) do
if Map.has_key?(properties, "housenumber") do
Map.get(properties, "housenumber") <> " " <> Map.get(properties, "street")
else
Map.get(properties, "street")
end
end
end