Class MemCache::Server
In: vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb
Parent: Object

This class represents a memcached server instance.

Methods

alive?   close   connect_to   inspect   mark_dead   new   socket  

Constants

RETRY_DELAY = 30.0   The amount of time to wait before attempting to re-establish a connection with a server that is marked dead.

Attributes

host  [R]  The host the memcached server is running on.
logger  [R] 
port  [R]  The port the memcached server is listening on.
retry  [R]  The time of next retry if the connection is dead.
status  [R]  A text status string describing the state of the server.
weight  [R]  The weight given to the server.

Public Class methods

Create a new MemCache::Server object for the memcached instance listening on the given host and port, weighted by the given weight.

[Source]

     # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 946
946:     def initialize(memcache, host, port = DEFAULT_PORT, weight = DEFAULT_WEIGHT)
947:       raise ArgumentError, "No host specified" if host.nil? or host.empty?
948:       raise ArgumentError, "No port specified" if port.nil? or port.to_i.zero?
949: 
950:       @host   = host
951:       @port   = port.to_i
952:       @weight = weight.to_i
953: 
954:       @sock   = nil
955:       @retry  = nil
956:       @status = 'NOT CONNECTED'
957:       @timeout = memcache.timeout
958:       @logger = memcache.logger
959:     end

Public Instance methods

Check whether the server connection is alive. This will cause the socket to attempt to connect if it isn‘t already connected and or if the server was previously marked as down and the retry time has been exceeded.

[Source]

     # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 974
974:     def alive?
975:       !!socket
976:     end

Close the connection to the memcached server targeted by this object. The server is not considered dead.

[Source]

      # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 1014
1014:     def close
1015:       @sock.close if @sock && !@sock.closed?
1016:       @sock   = nil
1017:       @retry  = nil
1018:       @status = "NOT CONNECTED"
1019:     end

[Source]

      # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 1004
1004:     def connect_to(host, port, timeout=nil)
1005:       io = MemCache::BufferedIO.new(TCPSocket.new(host, port))
1006:       io.read_timeout = timeout
1007:       io
1008:     end

Return a string representation of the server object.

[Source]

     # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 964
964:     def inspect
965:       "<MemCache::Server: %s:%d [%d] (%s)>" % [@host, @port, @weight, @status]
966:     end

Mark the server as dead and close its socket.

[Source]

      # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 1024
1024:     def mark_dead(error)
1025:       @sock.close if @sock && !@sock.closed?
1026:       @sock   = nil
1027:       @retry  = Time.now + RETRY_DELAY
1028: 
1029:       reason = "#{error.class.name}: #{error.message}"
1030:       @status = sprintf "%s:%s DEAD (%s), will retry at %s", @host, @port, reason, @retry
1031:       @logger.info { @status } if @logger
1032:     end

Try to connect to the memcached server targeted by this object. Returns the connected socket object on success or nil on failure.

[Source]

      # File vendor/rails/activesupport/lib/active_support/vendor/memcache-client-1.7.4/memcache.rb, line 982
 982:     def socket
 983:       return @sock if @sock and not @sock.closed?
 984: 
 985:       @sock = nil
 986: 
 987:       # If the host was dead, don't retry for a while.
 988:       return if @retry and @retry > Time.now
 989: 
 990:       # Attempt to connect if not already connected.
 991:       begin
 992:         @sock = connect_to(@host, @port, @timeout)
 993:         @sock.setsockopt Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1
 994:         @retry  = nil
 995:         @status = 'CONNECTED'
 996:       rescue SocketError, SystemCallError, IOError => err
 997:         logger.warn { "Unable to open socket: #{err.class.name}, #{err.message}" } if logger
 998:         mark_dead err
 999:       end
1000: 
1001:       return @sock
1002:     end

[Validate]