Refactor quote validation

lib/api.rb

@@ -26,6 +26,8 @@ helpers do
 
       ret
     end
+  rescue Quote::Invalid => ex
+    halt_with_message 422, ex.message
   end
 
   def symbols
@@ -37,14 +39,6 @@ helpers do
     end
   end
 
-  def transform_date
-    params[:date] = Date.new(
-      params.delete('year').to_i,
-      params.delete('month').to_i,
-      params.delete('day').to_i
-    )
-  end
-
   def halt_with_message(status, message)
     halt status, Yajl::Encoder.encode(error: message)
   end
@@ -59,17 +53,11 @@ get '/latest' do
   jsonp quote
 end
 
-get(/(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/) do
-  transform_date
+get(/(?<date>\d{4}-\d{2}-\d{2})/) do
   last_modified quote[:date]
-
   jsonp quote
 end
 
 not_found do
   halt_with_message 404, 'Not found'
 end
-
-error ArgumentError do
-  halt_with_message 422, env['sinatra.error'].message.capitalize
-end

lib/quote.rb

@@ -6,6 +6,8 @@ require 'currency'
 class Quote
   include Virtus.value_object
 
+  Invalid = Class.new(StandardError)
+
   DEFAULT_BASE = 'EUR'.freeze
 
   values do
@@ -23,9 +25,14 @@ class Quote
 
   def date=(date)
     current_date = Currency.current_date_before(date)
-    fail ArgumentError, 'Date too old' unless current_date
-
+    raise Invalid, 'Date too old' unless current_date
     super current_date
+  rescue Sequel::DatabaseError => ex
+    if ex.wrapped_exception.is_a?(PG::DatetimeFieldOverflow)
+      raise Invalid, 'Invalid date'
+    else
+      raise
+    end
   end
 
   def find_rates
@@ -45,7 +52,7 @@ class Quote
   def find_rebased_rates
     rates = find_default_rates
     denominator = rates.update(DEFAULT_BASE => 1.0).delete(base)
-    fail ArgumentError, 'Invalid base' unless denominator
+    raise Invalid, 'Invalid base' unless denominator
     rates.each do |iso_code, rate|
       rates[iso_code] = round_rate(rate / denominator)
     end

spec/quote_spec.rb

@@ -59,18 +59,26 @@ describe Quote do
   describe 'when given an invalid base' do
     let(:quote) { Quote.new(base: 'FOO') }
 
-    it 'fails' do
-      proc { quote.to_h }.must_raise ArgumentError
+    it 'raises validation error' do
+      proc { quote.to_h }.must_raise Quote::Invalid
     end
   end
 
   describe 'when given a date that is too old' do
-    let(:quote) { Quote.new(date: Date.new(1900)) }
+    let(:quote) { Quote.new(date: '1900-01-01') }
 
-    it 'fails' do
+    it 'raises validation error' do
       Currency.stub :current_date_before, nil do
-        proc { quote }.must_raise ArgumentError
+        proc { quote }.must_raise Quote::Invalid
       end
     end
   end
+
+  describe 'when given a bad date' do
+    let(:quote) { Quote.new(date: '2000-31-01') }
+
+    it 'raises validation error' do
+      proc { quote }.must_raise Quote::Invalid
+    end
+  end
 end