Add support for Redis unix sockets

docs/index.asciidoc

@@ -45,6 +45,7 @@ This plugin supports the following configuration options plus the <<plugins-{typ
 | <<plugins-{type}s-{plugin}-data_type>> |<<string,string>>, one of `["list", "channel", "pattern_channel"]`|Yes
 | <<plugins-{type}s-{plugin}-db>> |<<number,number>>|No
 | <<plugins-{type}s-{plugin}-host>> |<<string,string>>|No
+| <<plugins-{type}s-{plugin}-path>> |<<string,string>>|No
 | <<plugins-{type}s-{plugin}-key>> |<<string,string>>|Yes
 | <<plugins-{type}s-{plugin}-password>> |<<password,password>>|No
 | <<plugins-{type}s-{plugin}-port>> |<<number,number>>|No
@@ -89,9 +90,19 @@ The Redis database number.
 
   * Value type is <<string,string>>
   * Default value is `"127.0.0.1"`
+  * Path and Host are mutually exclusive - Logstash will throw an error if both are specified.
 
 The hostname of your Redis server.
 
+id="plugins-{type}s-{plugin}-path"]
+===== `path` 
+
+  * Value type is <<string,string>>
+  * There is no default value for this setting.
+  * Path and Host are mutually exclusive - Logstash will throw an error if both are specified.
+
+The unix socket path of your Redis server.
+
 [id="plugins-{type}s-{plugin}-key"]
 ===== `key` 
 

lib/logstash/inputs/redis.rb

@@ -23,12 +23,19 @@ module LogStash module Inputs class Redis < LogStash::Inputs::Threadable
 
   default :codec, "json"
 
-  # The hostname of your Redis server.
-  config :host, :validate => :string, :default => "127.0.0.1"
+  # The hostname of your Redis server
+  # This defaults to 127.0.0.1 if not specified.
+  # This and :path are mutually exclusive. Will raise an ArgumentError if both are specified.
+  config :host, :validate => :string
 
   # The port to connect on.
   config :port, :validate => :number, :default => 6379
 
+  # The unix socket path to connect on. Will override host and port if defined. 
+  # There is no unix socket path by default. 
+  # This and :host are mutually exclusive. Will raise an ArgumentError if both are specified.
+  config :path, :validate => :string
+
   # The Redis database number.
   config :db, :validate => :number, :default => 0
 
@@ -68,7 +75,15 @@ def new_redis_instance
   end
 
   def register
-    @redis_url = "redis://#{@password}@#{@host}:#{@port}/#{@db}"
+    if [email protected]? && [email protected]?
+      raise ArgumentError.new(
+          "Host and Path cannot be specified simultaneously. These options are exclusive."
+        )
+    elsif @host.nil? && @path.nil?
+      @host = "127.0.0.1"
+    end
+
+    @redis_url = @path.nil? ? "redis://#{@password}@#{@host}:#{@port}/#{@db}" : "#{@password}@#{@path}/#{@db}"
 
     @redis_builder ||= method(:internal_redis_builder)
 
@@ -114,13 +129,24 @@ def is_list_type?
 
   # private
   def redis_params
-    {
-      :host => @host,
-      :port => @port,
+    if @path.nil? 
+      connectionParams = {
+        :host => @host,
+        :port => @port
+      }
+    else
+      connectionParams = {
+        :path => @path
+      }
+    end
+
+    baseParams = {
       :timeout => @timeout,
       :db => @db,
       :password => @password.nil? ? nil : @password.value
     }
+
+    return connectionParams.merge(baseParams)
   end
 
   # private