Enforce default statefile location

lib/sufia/engine.rb

@@ -1,4 +1,12 @@
 module Sufia
+  class Statefile
+    def self.default
+      return '/tmp/minter-state' if Rails.env.development? || Rails.env.test?
+      raise NotImplementedError, "can't use the default statefile for production" unless Dir.exist?('/var/sufia')
+      '/var/sufia/minter-state'
+    end
+  end
+
   class Engine < ::Rails::Engine
     engine_name 'sufia'
 
@@ -79,7 +87,7 @@ class Engine < ::Rails::Engine
     # Noid identifiers
     config.enable_noids = true
     config.noid_template = '.reeddeeddk'
-    config.minter_statefile = '/tmp/minter-state'
+    config.minter_statefile = Statefile.default
     config.translate_uri_to_id = ActiveFedora::Noid.config.translate_uri_to_id
     config.translate_id_to_uri = ActiveFedora::Noid.config.translate_id_to_uri
 

spec/lib/sufia/statefile_spec.rb

@@ -0,0 +1,28 @@
+require 'spec_helper'
+
+describe Sufia::Statefile do
+  let(:default) { '/tmp/minter-state' }
+  let(:production_default) { '/var/sufia/minter-state' }
+
+  subject { described_class.default }
+
+  it { is_expected.to eq(default) }
+
+  context "when in development" do
+    before { allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new("development")) }
+    it { is_expected.to eq(default) }
+  end
+
+  context "when in production" do
+    before { allow(Rails).to receive(:env).and_return(ActiveSupport::StringInquirer.new("production")) }
+    context "with a missing default directory" do
+      it "raises an error" do
+        expect { subject }.to raise_error(NotImplementedError)
+      end
+    end
+    context "with a default directory" do
+      before { allow(Dir).to receive(:exist?).with(File.dirname(production_default)).and_return(true) }
+      it { is_expected.to eq(production_default) }
+    end
+  end
+end