Add GeoSpatial backends for geocoding

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

Geospatial Backend

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/service/geospatial/map_quest.ex

@@ -0,0 +1,116 @@
+defmodule Mobilizon.Service.Geospatial.MapQuest do
+  @moduledoc """
+  [MapQuest](https://developer.mapquest.com/documentation) backend.
+
+  ## Options
+  In addition to the [the shared options](Mobilizon.Service.Geospatial.Provider.html#module-shared-options),
+  MapQuest methods support the following options:
+  * `:open_data` Whether to use [Open Data or Licenced Data](https://developer.mapquest.com/documentation/open/).
+    Defaults to `true`
+  """
+  alias Mobilizon.Service.Geospatial.Provider
+  alias Mobilizon.Addresses.Address
+  require Logger
+
+  @behaviour Provider
+
+  @api_key Application.get_env(:mobilizon, __MODULE__) |> get_in([:api_key])
+
+  @api_key_missing_message "API Key required to use MapQuest"
+
+  @impl Provider
+  @doc """
+  MapQuest implementation for `c:Mobilizon.Service.Geospatial.Provider.geocode/3`.
+  """
+  @spec geocode(String.t(), keyword()) :: list(Address.t())
+  def geocode(lon, lat, options \\ []) do
+    api_key = Keyword.get(options, :api_key, @api_key)
+    limit = Keyword.get(options, :limit, 10)
+    open_data = Keyword.get(options, :open_data, true)
+
+    prefix = if open_data, do: "open", else: "www"
+
+    if is_nil(api_key), do: raise(ArgumentError, message: @api_key_missing_message)
+
+    with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <-
+           HTTPoison.get(
+             "https://#{prefix}.mapquestapi.com/geocoding/v1/reverse?key=#{api_key}&location=#{
+               lat
+             },#{lon}&maxResults=#{limit}"
+           ),
+         {:ok, %{"results" => results, "info" => %{"statuscode" => 0}}} <- Poison.decode(body) do
+      results |> Enum.map(&processData/1)
+    else
+      {:ok, %HTTPoison.Response{status_code: 403, body: err}} ->
+        raise(ArgumentError, message: err)
+    end
+  end
+
+  @impl Provider
+  @doc """
+  MapQuest implementation for `c:Mobilizon.Service.Geospatial.Provider.search/2`.
+  """
+  @spec search(String.t(), keyword()) :: list(Address.t())
+  def search(q, options \\ []) do
+    limit = Keyword.get(options, :limit, 10)
+    api_key = Keyword.get(options, :api_key, @api_key)
+
+    open_data = Keyword.get(options, :open_data, true)
+
+    prefix = if open_data, do: "open", else: "www"
+
+    if is_nil(api_key), do: raise(ArgumentError, message: @api_key_missing_message)
+
+    url =
+      "https://#{prefix}.mapquestapi.com/geocoding/v1/address?key=#{api_key}&location=#{
+        URI.encode(q)
+      }&maxResults=#{limit}"
+
+    Logger.debug("Asking MapQuest for addresses with #{url}")
+
+    with {:ok, %HTTPoison.Response{status_code: 200, body: body}} <-
+           HTTPoison.get(url),
+         {:ok, %{"results" => results, "info" => %{"statuscode" => 0}}} <- Poison.decode(body) do
+      results |> Enum.map(&processData/1)
+    else
+      {:ok, %HTTPoison.Response{status_code: 403, body: err}} ->
+        raise(ArgumentError, message: err)
+    end
+  end
+
+  defp processData(
+         %{
+           "locations" => addresses,
+           "providedLocation" => %{"latLng" => %{"lat" => lat, "lng" => lng}}
+         } = _body
+       ) do
+    case addresses do
+      [] -> nil
+      addresses -> addresses |> hd |> produceAddress(lat, lng)
+    end
+  end
+
+  defp processData(%{"locations" => addresses}) do
+    case addresses do
+      [] -> nil
+      addresses -> addresses |> hd |> produceAddress()
+    end
+  end
+
+  defp produceAddress(%{"latLng" => %{"lat" => lat, "lng" => lng}} = address) do
+    produceAddress(address, lat, lng)
+  end
+
+  defp produceAddress(address, lat, lng) do
+    %Address{
+      addressCountry: Map.get(address, "adminArea1"),
+      addressLocality: Map.get(address, "adminArea5"),
+      addressRegion: Map.get(address, "adminArea3"),
+      description: Map.get(address, "street"),
+      floor: Map.get(address, "floor"),
+      geom: [lng, lat] |> Provider.coordinates(),
+      postalCode: Map.get(address, "postalCode"),
+      streetAddress: Map.get(address, "street")
+    }
+  end
+end