TomTom: Provide `TomTom.batch(...)` method

This change enables us to call `TomTom.batch(...)` instead of
`TomTom.new.batch(...)` a couple commits ago. This is nice because the
initialisation was kind of unnecessary for users of the class.

Refs #6095

3 files changed, 20 insertions, 15 deletions

diff --git a/lib/tom_tom.rb b/lib/tom_tom.rb
index 2947961c3..97f914f28 100644
--- a/lib/tom_tom.rb
+++ b/lib/tom_tom.rb
@@ -1,2 +1,18 @@
 module TomTom
+  BASE_URL = 'https://api.tomtom.com'
+  API_KEY = Rails.application.secrets.tomtom_api_key
+
+  @connection = Faraday.new(
+    url: BASE_URL,
+    params: {
+      key: API_KEY
+    }
+  ) do |faraday|
+    faraday.use FaradayMiddleware::FollowRedirects, limit: 1
+    faraday.adapter Faraday.default_adapter
+  end
+
+  def self.batch(way_costs)
+    TomTom::Batch.new(@connection).batch(way_costs)
+  end
 end
diff --git a/lib/tom_tom/batch.rb b/lib/tom_tom/batch.rb
index 4d590a945..f947cced8 100644
--- a/lib/tom_tom/batch.rb
+++ b/lib/tom_tom/batch.rb
@@ -1,18 +1,7 @@
 module TomTom
   class Batch
-    BASE_URL = 'https://api.tomtom.com'
-    API_KEY = Rails.application.secrets.tomtom_api_key
-
-    def initialize
-      @connection = Faraday.new(
-        url: BASE_URL,
-        params: {
-          key: API_KEY
-        }
-      ) do |faraday|
-        faraday.use FaradayMiddleware::FollowRedirects, limit: 1
-        faraday.adapter Faraday.default_adapter
-      end
+    def initialize(connection)
+      @connection = connection
     end
 
     def batch(way_costs)
diff --git a/spec/lib/tom_tom/batch_spec.rb b/spec/lib/tom_tom/batch_spec.rb
index 5aff970eb..aee1a2f1d 100644
--- a/spec/lib/tom_tom/batch_spec.rb
+++ b/spec/lib/tom_tom/batch_spec.rb
@@ -1,5 +1,5 @@
 RSpec.describe TomTom::Batch do
-  let(:tomtom) { TomTom::Batch.new }
+  let(:batch) { TomTom::Batch.new(nil) }
 
   describe "#convert_way_costs_for_batch" do
     it "turns WayCost points into a collection of colon-separated strings" do
@@ -15,7 +15,7 @@ RSpec.describe TomTom::Batch do
       ]
 
       expect(
-        tomtom.convert_way_costs_for_batch(way_costs)
+        batch.convert_way_costs_for_batch(way_costs)
       ).to eq([
         '2,48:3,46',
         '-71,42:-71.5,42.9'