From 8f56f32d73a77420e1e87e4a1deb0a042798d82c Mon Sep 17 00:00:00 2001
From: Dan Buch <daniel.buch@gmail.com>
Date: Sun, 6 Sep 2015 09:15:49 -0400
Subject: [PATCH] Extract bits into a separate file for offline generation

---
 app.rb         | 21 +++++++++++++++++++++
 config.ru      |  4 ++--
 cpi_feed.rb    | 23 -----------------------
 cpi_fetcher.rb | 24 ++++++++++++++++++++++++
 4 files changed, 47 insertions(+), 25 deletions(-)
 create mode 100644 app.rb
 delete mode 100644 cpi_feed.rb
 create mode 100644 cpi_fetcher.rb

diff --git a/app.rb b/app.rb
new file mode 100644
index 0000000..15612d0
--- /dev/null
+++ b/app.rb
@@ -0,0 +1,21 @@
+require 'sinatra/base'
+require_relative 'cpi_fetcher'
+
+class App < Sinatra::Base
+  get '/' do
+    current_cpi = fetcher.cpi
+    halt 502 unless current_cpi
+
+    expires 300, :public, :must_revalidate
+    content_type :text
+    "#{current_cpi}\n"
+  end
+
+  run! if app_file == $PROGRAM_FILE
+
+  private
+
+  def fetcher
+    @fetcher ||= CPIFetcher.new
+  end
+end
diff --git a/config.ru b/config.ru
index d29d044..eae1e13 100644
--- a/config.ru
+++ b/config.ru
@@ -1,3 +1,3 @@
-require './cpi_feed'
+require './app'
 
-run CPIFeed
+run App
diff --git a/cpi_feed.rb b/cpi_feed.rb
deleted file mode 100644
index a389d90..0000000
--- a/cpi_feed.rb
+++ /dev/null
@@ -1,23 +0,0 @@
-require 'sinatra/base'
-require 'faraday'
-require 'json'
-
-class CPIFeed < Sinatra::Base
-  DEFAULT_CPI_SERIES_URL = 'http://api.bls.gov/publicAPI/v2/timeseries/data/CUUSA210SA0'
-
-  get '/' do
-    resp = JSON.parse(Faraday.get(cpi_series_url).body)
-
-    halt 502 unless resp['Results']['series']
-
-    expires 300, :public, :must_revalidate
-    content_type :csv
-    "#{resp['Results']['series'].first['data'].first['value']}\n"
-  end
-
-  def cpi_series_url
-    ENV['CPI_SERIES_URL'] || DEFAULT_CPI_SERIES_URL
-  end
-
-  run! if app_file == $PROGRAM_FILE
-end
diff --git a/cpi_fetcher.rb b/cpi_fetcher.rb
new file mode 100644
index 0000000..c32d551
--- /dev/null
+++ b/cpi_fetcher.rb
@@ -0,0 +1,24 @@
+require 'faraday'
+require 'json'
+
+class CPIFetcher
+  DEFAULT_CPI_SERIES_URL = 'http://api.bls.gov/publicAPI/v2/timeseries/data/CUUSA210SA0'
+  attr_reader :cpi_series_url
+
+  def initialize
+    @cpi_series_url = (ENV['CPI_SERIES_URL'] || DEFAULT_CPI_SERIES_URL)
+  end
+
+  def cpi
+    resp = JSON.parse(Faraday.get(cpi_series_url).body)
+
+    return nil unless resp['Results']['series']
+
+    resp['Results']['series'].first['data'].first['value']
+  end
+end
+
+if $PROGRAM_NAME == __FILE__
+  puts CPIFetcher.new.cpi
+  exit 0
+end