Start ThrottlePolicy class

app/lib/throttle_policy.rb

@@ -0,0 +1,18 @@
+#
+class ThrottlePolicy
+  attr_reader :rules
+
+  # A throttler object paired with a max limit
+  class Rule
+    attr_reader :throttle, :limit
+
+    def initialize(throttle, limit)
+      @throttle, @limit = throttle, limit
+    end
+  end
+
+  # Dictionary<Throttler, number>
+  def initialize(policy_rules)
+    @rules = policy_rules.map { |rule_set| Rule.new(*rule_set) }
+  end
+end

spec/lib/throttle_policy_spec.rb

@@ -0,0 +1,15 @@
+require "spec_helper"
+NOW = Time.new("2018-05-18T09:38:02.259-05:00")
+
+describe Throttler do
+  it "initializes" do
+    policy = ThrottlePolicy.new(Throttler.new(1.minute, NOW) => 1_000,
+                                Throttler.new(1.hour,   NOW) => 10_000,
+                                Throttler.new(1.day,    NOW) => 100_000)
+    expect(policy.rules).to be
+    expect(policy.rules.map(&:limit).sort).to eq([1000, 10000, 100000])
+    actual   = policy.rules.map(&:throttle).map(&:time_unit_in_seconds).sort
+    expected = [1.minute, 1.hour, 1.day]
+    expect(actual).to eq(expected)
+  end
+end