From 7788ec0e72ec9077e23039adb1618d4185035eb6 Mon Sep 17 00:00:00 2001
From: Brian Durand <bdurand@bdurand.local>
Date: Thu, 22 Apr 2010 20:59:05 -0500
Subject: [PATCH] Ensure that ActiveSupport::Cache keys can be of any length and not limited by the implementation.

---
 .../lib/active_support/cache/file_store.rb         |   14 +++++++-
 .../lib/active_support/cache/mem_cache_store.rb    |   15 ++++-----
 activesupport/test/caching_test.rb                 |   31 +++++++++++++-------
 3 files changed, 39 insertions(+), 21 deletions(-)

diff --git a/activesupport/lib/active_support/cache/file_store.rb b/activesupport/lib/active_support/cache/file_store.rb
index bff80f7..8656d8b 100644
--- a/activesupport/lib/active_support/cache/file_store.rb
+++ b/activesupport/lib/active_support/cache/file_store.rb
@@ -117,12 +117,22 @@ module ActiveSupport
           hash = Zlib.adler32(fname)
           hash, dir_1 = hash.divmod(0x1000)
           dir_2 = hash.modulo(0x1000)
-          File.join(cache_path, DIR_FORMATTER % dir_1, DIR_FORMATTER % dir_2, fname)
+          fname_paths = []
+          # Make sure file name is < 255 characters so it doesn't exceed file system limits.
+          if fname.size <= 255
+            fname_paths << fname
+          else
+            while fname.size <= 255
+              fname_path << fname[0, 255]
+              fname = fname[255, -1]
+            end
+          end
+          File.join(cache_path, DIR_FORMATTER % dir_1, DIR_FORMATTER % dir_2, *fname_paths)
         end
 
         # Translate a file path into a key.
         def file_path_key (path)
-          fname = File.basename(path)
+          fname = path[cache_path.size, path.size].split(File::SEPARATOR, 4).last
           fname.gsub(UNESCAPE_FILENAME_CHARS){|match| $1.to_s(16)}
         end
 
diff --git a/activesupport/lib/active_support/cache/mem_cache_store.rb b/activesupport/lib/active_support/cache/mem_cache_store.rb
index 432ece6..66a9400 100644
--- a/activesupport/lib/active_support/cache/mem_cache_store.rb
+++ b/activesupport/lib/active_support/cache/mem_cache_store.rb
@@ -1,4 +1,5 @@
 require 'memcache'
+require 'md5'
 
 module ActiveSupport
   module Cache
@@ -25,7 +26,6 @@ module ActiveSupport
       end
 
       ESCAPE_KEY_CHARS = /[\x00-\x20%\x7F-\xFF]/
-      UNESCAPE_KEY_CHARS = /%[0-9A-F]{2}/
 
       def self.build_mem_cache(*addresses)
         addresses = addresses.flatten
@@ -69,11 +69,12 @@ module ActiveSupport
       def read_multi(*names)
         options = names.extract_options!
         options = merged_options(options)
-        raw_values = @data.get_multi(names.collect{|n| escape_key(namespaced_key(n, options))}, :raw => true)
+        keys_to_names = names.inject({}){|map, name| map[escape_key(namespaced_key(name, options))] = name; map}
+        raw_values = @data.get_multi(keys_to_names.keys, :raw => true)
         values = {}
         raw_values.each do |key, value|
           entry = deserialize_entry(value)
-          values[unescape_key(key)] = entry.value unless entry.expired?
+          values[keys_to_names[key]] = entry.value unless entry.expired?
         end
         values
       end
@@ -153,11 +154,9 @@ module ActiveSupport
 
       private
         def escape_key (key)
-          key.to_s.gsub(ESCAPE_KEY_CHARS){|match| "%#{match[0].to_s(16).upcase}"}
-        end
-
-        def unescape_key (key)
-          key.gsub(UNESCAPE_KEY_CHARS){|match| $1.to_s(16)}
+          key = key.to_s.gsub(ESCAPE_KEY_CHARS){|match| "%#{match[0].to_s(16).upcase}"}
+          key = "#{key[0, 213]}:md5:#{MD5.md5(key).to_s}" if key.size > 250
+          key
         end
 
         def deserialize_entry (raw_value)
diff --git a/activesupport/test/caching_test.rb b/activesupport/test/caching_test.rb
index 88466e9..5ee88d4 100644
--- a/activesupport/test/caching_test.rb
+++ b/activesupport/test/caching_test.rb
@@ -304,6 +304,26 @@ module CacheStoreBehavior
     Time.stubs(:now).returns(time + 71)
     assert_nil @cache.read('foo')
   end
+  
+  def test_crazy_key_characters
+    crazy_key = "#/:*(<+=> )&$%@?;'\"\'`~-"
+    assert_equal true, @cache.write(crazy_key, "1", :raw => true)
+    assert_equal "1", @cache.read(crazy_key)
+    assert_equal "1", @cache.fetch(crazy_key)
+    assert_equal true, @cache.delete(crazy_key)
+    assert_equal "2", @cache.fetch(crazy_key, :raw => true) { "2" }
+    assert_equal 3, @cache.increment(crazy_key)
+    assert_equal 2, @cache.decrement(crazy_key)
+  end
+  
+  def test_really_long_keys
+    key = ""
+    1000.times{key << "x"}
+    assert_equal true, @cache.write(key, "bar")
+    assert_equal "bar", @cache.read(key)
+    assert_equal({key => "bar"}, @cache.read_multi(key))
+    assert_equal true, @cache.delete(key)
+  end
 end
 
 module CacheKeysIteratorBehavior
@@ -403,17 +423,6 @@ module LocalCacheBehavior
     app = @cache.middleware.new(app)
     app.call({})
   end
-  
-  def test_crazy_key_characters
-    crazy_key = "#/:*(<+=> )&$%@?;'\"\'`~-"
-    assert_equal true, @cache.write(crazy_key, "1", :raw => true)
-    assert_equal "1", @cache.read(crazy_key)
-    assert_equal "1", @cache.fetch(crazy_key)
-    assert_equal true, @cache.delete(crazy_key)
-    assert_equal "2", @cache.fetch(crazy_key, :raw => true) { "2" }
-    assert_equal 3, @cache.increment(crazy_key)
-    assert_equal 2, @cache.decrement(crazy_key)
-  end
 end
 
 class FileStoreTest < ActiveSupport::TestCase
-- 
1.6.4.1