From 64e4b4a66a10872ebdcb5f8ee0e612ecb95a6029 Mon Sep 17 00:00:00 2001
From: Adrian Gonzalez <adrian@healthloop.com>
Date: Thu, 9 Jul 2015 16:49:11 -0700
Subject: [PATCH] add test for long cache keys

---
 lib/cached_resource/caching.rb       | 12 ++++++++++--
 spec/cached_resource/caching_spec.rb |  9 +++++++++
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/cached_resource/caching.rb b/lib/cached_resource/caching.rb
index a0eb457..b15023e 100644
--- a/lib/cached_resource/caching.rb
+++ b/lib/cached_resource/caching.rb
@@ -4,6 +4,8 @@ module CachedResource
   module Caching
     extend ActiveSupport::Concern
 
+    MAX_ARGUMENTS_CACHE_SIZE = 150
+
     included do
       class << self
         alias_method_chain :find, :cache
@@ -112,10 +114,16 @@ def cache_clear
 
       # Generate the request cache key.
       def cache_key(*arguments)
+        "#{name.parameterize.gsub("-", "/")}/#{arguments_cache_key(*arguments)}".downcase.delete(' ')
+      end
+
+      def arguments_cache_key(*arguments)
         arguments_string = arguments.join('/')
-        arguments_key = arguments_string.length > 150 ? Digest::SHA2.hexdigest(arguments_string) : arguments_string
+        arguments_string.length > MAX_ARGUMENTS_CACHE_SIZE ? hash_string(arguments_string) : arguments_string
+      end
 
-        "#{name.parameterize.gsub("-", "/")}/#{arguments_key}".downcase.delete(' ')
+      def hash_string(string)
+        Digest::SHA2.hexdigest(string)
       end
 
       # Make a full duplicate of an ActiveResource record.
diff --git a/spec/cached_resource/caching_spec.rb b/spec/cached_resource/caching_spec.rb
index b728e0e..0d9252d 100644
--- a/spec/cached_resource/caching_spec.rb
+++ b/spec/cached_resource/caching_spec.rb
@@ -56,6 +56,14 @@ class Thing < ActiveResource::Base
       Thing.cached_resource.cache.read('thing/1/{:from=>"path",:params=>{:foo=>"bar"}}').should == result
     end
 
+    it "should hash long parameters in cache key" do
+      params = [1, {long_params: "l" * Thing::MAX_ARGUMENTS_CACHE_SIZE }]
+      hash_params = Thing.send(:hash_string, params.join("/"))
+
+      result = Thing.find(*params)
+      Thing.cached_resource.cache.read("thing/#{hash_params}").should == result
+    end
+
     it "should empty the cache when clear_cache is called" do
       result = Thing.find(1)
       Thing.clear_cache
@@ -510,4 +518,5 @@ class CustomCollection < ActiveResource::Collection; end
       new_result.name.should_not == old_result.name
     end
   end
+
 end