client-libraries/ruby_2/rubyredis.rb

   1 # RubyRedis is an alternative implementatin of Ruby client library written
   2 # by Salvatore Sanfilippo.
   3 #
   4 # The aim of this library is to create an alternative client library that is
   5 # much simpler and does not implement every command explicitly but uses
   6 # method_missing instead.
   7
   8 require 'socket'
   9
  10 class RedisClient
  11     BulkCommands = {
  12         "set"=>true, "setnx"=>true, "rpush"=>true, "lpush"=>true, "lset"=>true,
  13         "lrem"=>true, "sadd"=>true, "srem"=>true, "sismember"=>true,
  14         "echo"=>true, "getset"=>true, "smove"=>true
  15     }
  16
  17     def initialize(opts={})
  18         opts = {:host => 'localhost', :port => '6379', :db => 0}.merge(opts)
  19         @host = opts[:host]
  20         @port = opts[:port]
  21         @db = opts[:db]
  22         @sock = connect_to_server
  23     end
  24
  25     def to_s
  26         "Redis Client connected to #{@host}:#{@port} against DB #{@db}"
  27     end
  28
  29     def connect_to_server
  30         TCPSocket.new(@host, @port, 0)
  31     end
  32
  33     def method_missing(*argv)
  34         call_command(argv)
  35     end
  36
  37     def call_command(argv)
  38         bulk = nil
  39         argv[0] = argv[0].to_s.downcase
  40         if BulkCommands[argv[0]]
  41             bulk = argv[-1]
  42             argv[-1] = bulk.length
  43         end
  44         @sock.write(argv.join(" ")+"\r\n")
  45         @sock.write(bulk+"\r\n") if bulk
  46         read_reply
  47     end
  48
  49     def read_reply
  50         line = @sock.gets
  51         case line[0..0]
  52         when "-"
  53             raise line.strip
  54         when "+"
  55             line[1..-1].strip
  56         when ":"
  57             line[1..-1].to_i
  58         when "$"
  59             bulklen = line[1..-1].to_i
  60             return nil if bulklen == -1
  61             data = @sock.read(bulklen)
  62             @sock.read(2) # CRLF
  63             data
  64         when "*"
  65             objects = line[1..-1].to_i
  66             return nil if bulklen == -1
  67             res = []
  68             objects.times {
  69                 res << read_reply
  70             }
  71             res
  72         end
  73     end
  74 end