Prototype de convertisseur NeTEx -> GeoJSON

apps/transport/lib/netex/geojson_converter.ex

@@ -0,0 +1,58 @@
+defmodule Transport.NeTEx.GeoJSONConverter do
+  @moduledoc """
+  A first converter to extract stop places and display it as a GeoJSON.
+  """
+
+  @doc """
+  Reads a NeTEx zip archive stored on disk, and returns a GeoJSON.
+  """
+  @spec convert(binary()) :: binary()
+  def convert(zip_file_name) do
+    {:ok, result} =
+      zip_file_name
+      |> collect_stop_places()
+      |> to_geojson_feature_collection()
+      |> Jason.encode()
+
+    result
+  end
+
+  def collect_stop_places(zip_file_name) do
+    zip_file_name
+    |> Transport.NeTEx.read_all_stop_places()
+    |> Enum.flat_map(&keep_stop_places_with_location/1)
+  end
+
+  @spec keep_stop_places_with_location({binary(), list()}) :: list()
+  defp keep_stop_places_with_location({_filename, stop_places}) do
+    Enum.filter(stop_places, &has_location?/1)
+  end
+
+  @spec has_location?(map()) :: boolean()
+  defp has_location?(stop_place) do
+    Map.has_key?(stop_place, :latitude) && Map.has_key?(stop_place, :longitude)
+  end
+
+  defp to_geojson_feature_collection(features) do
+    %{
+      type: "FeatureCollection",
+      features: Enum.map(features, &to_geojson_feature/1)
+    }
+  end
+
+  defp to_geojson_feature(%{latitude: latitude, longitude: longitude, name: name}) do
+    %{
+      type: "Feature",
+      geometry: %{
+        type: "Point",
+        coordinates: [longitude, latitude]
+      },
+      properties: %{
+        name: name
+      }
+    }
+  end
+
+  defp to_geojson_feature(%{id: id, latitude: latitude, longitude: longitude}),
+    do: to_geojson_feature(%{latitude: latitude, longitude: longitude, name: id})
+end

apps/transport/test/netex/geojson_converter_test.exs

@@ -0,0 +1,73 @@
+defmodule Transport.NeTEx.GeoJSONConverterTest do
+  use ExUnit.Case, async: true
+
+  alias Transport.ZipCreator
+
+  # not fully correct XML, but close enough for what we want to test
+  def some_netex_content do
+    """
+      <GeneralFrame>
+        <members>
+          <StopPlace id="FR:HELLO:POYARTIN:001">
+            <Name>Poyartin</Name>
+            <Centroid>
+              <Location>
+                <Latitude>43.6690</Latitude>
+                <Longitude>-0.9190</Longitude>
+              </Location>
+            </Centroid>
+          </StopPlace>
+          <StopPlace id="FR:HELLO:DAX:001">
+            <Name>Dax</Name>
+            <Centroid>
+              <Location>
+                <Latitude>43.7154</Latitude>
+                <Longitude>-1.0530</Longitude>
+              </Location>
+            </Centroid>
+          </StopPlace>
+        </members>
+      </GeneralFrame>
+    """
+  end
+
+  test "valid JSON from valid NeTEx" do
+    tmp_file = System.tmp_dir!() |> Path.join("temp-netex-#{Ecto.UUID.generate()}.zip")
+
+    netex_files = [
+      {"arrets_1.xml", some_netex_content()},
+      {"arrets_2.xml", some_netex_content()}
+    ]
+
+    ZipCreator.create!(tmp_file, netex_files)
+
+    result = Transport.NeTEx.GeoJSONConverter.convert(tmp_file)
+
+    assert {:ok,
+            %{
+              type: "FeatureCollection",
+              features: [
+                %{
+                  type: "Feature",
+                  geometry: %{type: "Point", coordinates: [-0.919, 43.669]},
+                  properties: %{name: "Poyartin"}
+                },
+                %{
+                  type: "Feature",
+                  geometry: %{type: "Point", coordinates: [-1.053, 43.7154]},
+                  properties: %{name: "Dax"}
+                },
+                %{
+                  type: "Feature",
+                  geometry: %{type: "Point", coordinates: [-0.919, 43.669]},
+                  properties: %{name: "Poyartin"}
+                },
+                %{
+                  type: "Feature",
+                  geometry: %{type: "Point", coordinates: [-1.053, 43.7154]},
+                  properties: %{name: "Dax"}
+                }
+              ]
+            }} = Jason.decode(result, keys: :atoms)
+  end
+end

apps/transport/test/netex/netex_archive_parser_test.exs

@@ -1,21 +1,7 @@
 defmodule Transport.NeTEx.ArchiveParserTest do
   use ExUnit.Case, async: true
 
-  defmodule ZipCreator do
-    @moduledoc """
-    A light wrapper around OTP `:zip` features. Does not support streaming here,
-    but massages the string <-> charlist differences.
-    """
-    @spec create!(String.t(), [{String.t(), binary()}]) :: no_return()
-    def create!(zip_filename, file_data) do
-      {:ok, ^zip_filename} =
-        :zip.create(
-          zip_filename,
-          file_data
-          |> Enum.map(fn {name, content} -> {name |> to_charlist(), content} end)
-        )
-    end
-  end
+  alias Transport.ZipCreator
 
   # not fully correct XML, but close enough for what we want to test
   def some_netex_content do

apps/transport/test/support/zip_creator.ex

@@ -0,0 +1,16 @@
+defmodule Transport.ZipCreator do
+  @moduledoc """
+  A light wrapper around OTP `:zip` features. Does not support streaming here,
+  but massages the string <-> charlist differences.
+  """
+  def create!(zip_filename, file_data) do
+    {:ok, ^zip_filename} =
+      :zip.create(
+        zip_filename,
+        file_data
+        |> Enum.map(fn {name, content} -> {name |> to_charlist(), content} end)
+      )
+
+    :ok
+  end
+end