Add `WayCostCollectionJSONSerializer`

A JSON serialiser for a collection of `WayCost`s. This will be used to
store `WayCost`s for a `Chouette::Route` in the `Route#costs` JSON
field.

Refs #6095

1 files changed, 16 insertions, 0 deletions

diff --git a/lib/way_cost_collection_json_serializer.rb b/lib/way_cost_collection_json_serializer.rb
new file mode 100644
index 000000000..191871cca
--- /dev/null
+++ b/lib/way_cost_collection_json_serializer.rb
@@ -0,0 +1,16 @@
+class WayCostCollectionJSONSerializer
+  def self.dump(way_costs)
+    return if way_costs.nil?
+
+    costs_by_id = {}
+
+    way_costs.each do |way_cost|
+      costs_by_id[way_cost.id] = {
+        distance: way_cost.distance,
+        time: way_cost.time
+      }
+    end
+
+    JSON.dump(costs_by_id)
+  end
+end