BUGFIX: redis-rails has always been a problem child

implemented an ActiveSupport::Cache::Store for our internal use.
* allows for expire by family
* works correctly in multisite
* namespaced correctly

Removed redis-rails from the project, no longer needed

lib/cache.rb

@@ -1,55 +1,72 @@
-# Standard Rails.cache is lacking support for this interface, possibly yank all in from redis:cache and start using this instead
-#
+# Discourse specific cache supports expire by family missing from standard cache
 
-class Cache
-  def initialize(redis=nil)
-    @redis = redis
+class Cache < ActiveSupport::Cache::Store
+
+  def initialize(opts = {})
+    opts[:namespace] ||= "_CACHE_"
+    super(opts)
   end
 
   def redis
-    @redis || $redis
-  end
-
-  def fetch(key, options={})
-    result = redis.get key
-    if result.nil?
-      if expiry = options[:expires_in]
-        if block_given?
-          result = yield
-          redis.setex(key, expiry, result)
-        end
-      else
-        if block_given?
-          result = yield
-          redis.set(key, result)
-        end
-      end
-    end
-
-    if family = family_key(options[:family])
-      redis.sadd(family, key)
-    end
-
-    result
-  end
-
-  def delete(key)
-    redis.del(key)
+    $redis
   end
 
   def delete_by_family(key)
-    k = family_key(key)
+    k = family_key(key, options)
     redis.smembers(k).each do |member|
-      delete(member)
+      redis.del(member)
     end
     redis.del(k)
   end
 
-  private
+  def reconnect
+    redis.reconnect
+  end
 
-  def family_key(name)
-    if name
-      "FAMILY_#{name}"
+  def clear
+    redis.keys.each do |k|
+      redis.del(k) if k =~ /^_CACHE_:/
     end
   end
+
+  def namespaced_key(key, opts=nil)
+    opts ||= options
+    super(key,opts)
+  end
+
+  protected
+
+  def read_entry(key, options)
+    if data = redis.get(key)
+      ActiveSupport::Cache::Entry.new data
+    end
+  end
+
+  def write_entry(key, entry, options)
+    if expiry = options[:expires_in]
+      redis.setex(key, expiry, entry.value)
+    else
+      redis.set(key, entry.value)
+    end
+
+    if family = family_key(options[:family], options)
+      redis.sadd(family, key)
+    end
+
+    true
+  end
+
+  def delete_entry(key, options)
+    redis.del key
+  end
+
+  private
+
+  def family_key(name, options)
+    if name
+      key = namespaced_key(name, options)
+      key << "FAMILY:#{name}"
+    end
+  end
+
 end

lib/discourse_redis.rb

@@ -1,6 +1,7 @@
 #
 #  A wrapper around redis that namespaces keys with the current site id
 #
+require_dependency 'cache'
 class DiscourseRedis
 
   def self.raw_connection(config = nil)
@@ -43,7 +44,7 @@ class DiscourseRedis
   end
 
   # Proxy key methods through, but prefix the keys with the namespace
-  [:append, :blpop, :brpop, :brpoplpush, :decr, :decrby, :del, :exists, :expire, :expireat, :get, :getbit, :getrange, :getset,
+  [:append, :blpop, :brpop, :brpoplpush, :decr, :decrby, :exists, :expire, :expireat, :get, :getbit, :getrange, :getset,
    :hdel, :hexists, :hget, :hgetall, :hincrby, :hincrbyfloat, :hkeys, :hlen, :hmget, :hmset, :hset, :hsetnx, :hvals, :incr,
    :incrby, :incrbyfloat, :lindex, :linsert, :llen, :lpop, :lpush, :lpushx, :lrange, :lrem, :lset, :ltrim,
    :mapped_hmset, :mapped_hmget, :mapped_mget, :mapped_mset, :mapped_msetnx, :mget, :move, :mset,
@@ -57,20 +58,32 @@ class DiscourseRedis
     end
   end
 
+  def del(k)
+    k = "#{DiscourseRedis.namespace}:#{k}"
+    @redis.del k
+  end
+
+  def keys
+    len = DiscourseRedis.namespace.length + 1
+    @redis.keys("#{DiscourseRedis.namespace}:*").map{
+      |k| k[len..-1]
+    }
+  end
+
+  def flushdb
+    keys.each{|k| del(k)}
+  end
+
+  def reconnect
+    @redis.client.reconnect
+  end
+
   def self.namespace
     RailsMultisite::ConnectionManagement.current_db
   end
 
   def self.new_redis_store
-    redis_config = YAML.load(ERB.new(File.new("#{Rails.root}/config/redis.yml").read).result)[Rails.env]
-    unless redis_config
-      puts '', "Redis config for environment '#{Rails.env}' was not found in #{Rails.root}/config/redis.yml."
-      puts "Did you forget to do RAILS_ENV=production?"
-      puts "Check your redis.yml and make sure it has configuration for the environment you're trying to use.", ''
-      raise 'Redis config not found'
-    end
-    ActiveSupport::Cache::RedisStore.new host:redis_config['host'], port:redis_config['port'], password:redis_config['password'], db:redis_config['db'], namespace:->{ DiscourseRedis.namespace + "_cache" }
+    Cache.new
   end
 
-
 end

lib/pretty_text.rb

@@ -59,7 +59,7 @@ module PrettyText
               "vendor/assets/javascripts/rsvp.js",
               Rails.configuration.ember.handlebars_location)
 
-    ctx.eval("var Discourse = {}; Discourse.SiteSettings = #{SiteSetting.client_settings_json};")
+    ctx.eval("var Discourse = {}; Discourse.SiteSettings = {};")
     ctx.eval("var window = {}; window.devicePixelRatio = 2;") # hack to make code think stuff is retina
     ctx.eval("var I18n = {}; I18n.t = function(a,b){ return helpers.t(a,b); }");