Bump vendored memcache to 1.7.5

1 files changed, 292 insertions, 93 deletions

diff --git a/activesupport/lib/active_support/vendor/memcache-client-1.6.5/lib/memcache.rb b/activesupport/lib/active_support/vendor/memcache-client-1.7.5/lib/memcache.rb
index 4d594c2089..3adc172a8f 100644
--- a/activesupport/lib/active_support/vendor/memcache-client-1.6.5/lib/memcache.rb
+++ b/activesupport/lib/active_support/vendor/memcache-client-1.7.5/lib/memcache.rb
@@ -2,9 +2,9 @@ $TESTING = defined?($TESTING) && $TESTING
 
 require 'socket'
 require 'thread'
-require 'timeout'
 require 'zlib'
 require 'digest/sha1'
+require 'net/protocol'
 
 ##
 # A Ruby client library for memcached.
@@ -15,18 +15,22 @@ class MemCache
   ##
   # The version of MemCache you are using.
 
-  VERSION = '1.6.4.99'
+  VERSION = '1.7.5'
 
   ##
   # Default options for the cache object.
 
   DEFAULT_OPTIONS = {
-    :namespace   => nil,
-    :readonly    => false,
-    :multithread => true,
-    :failover    => true,
-    :timeout     => 0.5,
-    :logger      => nil,
+    :namespace    => nil,
+    :readonly     => false,
+    :multithread  => true,
+    :failover     => true,
+    :timeout      => 0.5,
+    :logger       => nil,
+    :no_reply     => false,
+    :check_size   => true,
+    :autofix_keys => false,
+    :namespace_separator => ':',
   }
 
   ##
@@ -50,6 +54,19 @@ class MemCache
   attr_reader :multithread
 
   ##
+  # Whether to try to fix keys that are too long and will be truncated by
+  # using their SHA1 hash instead.
+  # The hash is only used on keys longer than 250 characters, or containing spaces,
+  # to avoid impacting performance unnecesarily.
+  #
+  # In theory, your code should generate correct keys when calling memcache, 
+  # so it's your responsibility and you should try to fix this problem at its source.
+  #
+  # But if that's not possible, enable this option and memcache-client will give you a hand.
+  
+  attr_reader :autofix_keys
+  
+  ##
   # The servers this client talks to.  Play at your own peril.
 
   attr_reader :servers
@@ -72,19 +89,32 @@ class MemCache
   attr_reader :logger
 
   ##
+  # Don't send or look for a reply from the memcached server for write operations.
+  # Please note this feature only works in memcached 1.2.5 and later.  Earlier
+  # versions will reply with "ERROR".
+  attr_reader :no_reply
+
+  ##
   # Accepts a list of +servers+ and a list of +opts+.  +servers+ may be
   # omitted.  See +servers=+ for acceptable server list arguments.
   #
   # Valid options for +opts+ are:
   #
-  #   [:namespace]   Prepends this value to all keys added or retrieved.
-  #   [:readonly]    Raises an exception on cache writes when true.
-  #   [:multithread] Wraps cache access in a Mutex for thread safety.
-  #   [:failover]    Should the client try to failover to another server if the
-  #                  first server is down?  Defaults to true.
-  #   [:timeout]     Time to use as the socket read timeout.  Defaults to 0.5 sec,
-  #                  set to nil to disable timeouts (this is a major performance penalty in Ruby 1.8).
-  #   [:logger]      Logger to use for info/debug output, defaults to nil
+  #   [:namespace]    Prepends this value to all keys added or retrieved.
+  #   [:readonly]     Raises an exception on cache writes when true.
+  #   [:multithread]  Wraps cache access in a Mutex for thread safety. Defaults to true.
+  #   [:failover]     Should the client try to failover to another server if the
+  #                   first server is down?  Defaults to true.
+  #   [:timeout]      Time to use as the socket read timeout.  Defaults to 0.5 sec,
+  #                   set to nil to disable timeouts.
+  #   [:logger]       Logger to use for info/debug output, defaults to nil
+  #   [:no_reply]     Don't bother looking for a reply for write operations (i.e. they
+  #                   become 'fire and forget'), memcached 1.2.5 and later only, speeds up
+  #                   set/add/delete/incr/decr significantly.
+  #   [:check_size]   Raises a MemCacheError if the value to be set is greater than 1 MB, which
+  #                   is the maximum key size for the standard memcached server.  Defaults to true.
+  #   [:autofix_keys] If a key is longer than 250 characters or contains spaces, 
+  #                   use an SHA1 hash instead, to prevent collisions on truncated keys.
   # Other options are ignored.
 
   def initialize(*args)
@@ -108,13 +138,17 @@ class MemCache
     end
 
     opts = DEFAULT_OPTIONS.merge opts
-    @namespace   = opts[:namespace]
-    @readonly    = opts[:readonly]
-    @multithread = opts[:multithread]
-    @timeout     = opts[:timeout]
-    @failover    = opts[:failover]
-    @logger      = opts[:logger]
-    @mutex       = Mutex.new if @multithread
+    @namespace    = opts[:namespace]
+    @readonly     = opts[:readonly]
+    @multithread  = opts[:multithread]
+    @autofix_keys = opts[:autofix_keys]
+    @timeout      = opts[:timeout]
+    @failover     = opts[:failover]
+    @logger       = opts[:logger]
+    @no_reply     = opts[:no_reply]
+    @check_size   = opts[:check_size]
+    @namespace_separator = opts[:namespace_separator]
+    @mutex        = Mutex.new if @multithread
 
     logger.info { "memcache-client #{VERSION} #{Array(servers).inspect}" } if logger
 
@@ -192,8 +226,8 @@ class MemCache
 
   def get(key, raw = false)
     with_server(key) do |server, cache_key|
+      logger.debug { "get #{key} from #{server.inspect}" } if logger
       value = cache_get server, cache_key
-      logger.debug { "GET #{key} from #{server.inspect}: #{value ? value.to_s.size : 'nil'}" } if logger
       return nil if value.nil?
       value = Marshal.load value unless raw
       return value
@@ -203,6 +237,25 @@ class MemCache
   end
 
   ##
+  # Performs a +get+ with the given +key+.  If 
+  # the value does not exist and a block was given,
+  # the block will be called and the result saved via +add+.
+  #
+  # If you do not provide a block, using this
+  # method is the same as using +get+.
+  #
+  def fetch(key, expiry = 0, raw = false)
+    value = get(key, raw)
+
+    if value.nil? && block_given?
+      value = yield
+      add(key, value, expiry, raw)
+    end
+
+    value
+  end
+
+  ##
   # Retrieves multiple values from memcached in parallel, if possible.
   #
   # The memcached protocol supports the ability to retrieve multiple
@@ -280,18 +333,64 @@ class MemCache
 
   def set(key, value, expiry = 0, raw = false)
     raise MemCacheError, "Update of readonly cache" if @readonly
+
+    value = Marshal.dump value unless raw
     with_server(key) do |server, cache_key|
+      logger.debug { "set #{key} to #{server.inspect}: #{value.to_s.size}" } if logger
 
-      value = Marshal.dump value unless raw
-      logger.debug { "SET #{key} to #{server.inspect}: #{value ? value.to_s.size : 'nil'}" } if logger
+      if @check_size && value.to_s.size > ONE_MB
+        raise MemCacheError, "Value too large, memcached can only store 1MB of data per key"
+      end
 
-      data = value.to_s
-      raise MemCacheError, "Value too large, memcached can only store 1MB of data per key" if data.size > ONE_MB
+      command = "set #{cache_key} 0 #{expiry} #{value.to_s.size}#{noreply}\r\n#{value}\r\n"
 
-      command = "set #{cache_key} 0 #{expiry} #{data.size}\r\n#{data}\r\n"
+      with_socket_management(server) do |socket|
+        socket.write command
+        break nil if @no_reply
+        result = socket.gets
+        raise_on_error_response! result
+
+        if result.nil?
+          server.close
+          raise MemCacheError, "lost connection to #{server.host}:#{server.port}"
+        end
+
+        result
+      end
+    end
+  end
+
+  ##
+  # "cas" is a check and set operation which means "store this data but
+  # only if no one else has updated since I last fetched it."  This can
+  # be used as a form of optimistic locking.
+  #
+  # Works in block form like so:
+  #   cache.cas('some-key') do |value|
+  #     value + 1
+  #   end
+  #
+  # Returns:
+  # +nil+ if the value was not found on the memcached server.
+  # +STORED+ if the value was updated successfully
+  # +EXISTS+ if the value was updated by someone else since last fetch
+
+  def cas(key, expiry=0, raw=false)
+    raise MemCacheError, "Update of readonly cache" if @readonly
+    raise MemCacheError, "A block is required" unless block_given?
+
+    (value, token) = gets(key, raw)
+    return nil unless value
+    updated = yield value
+    value = Marshal.dump updated unless raw
+
+    with_server(key) do |server, cache_key|
+      logger.debug { "cas #{key} to #{server.inspect}: #{value.to_s.size}" } if logger
+      command = "cas #{cache_key} 0 #{expiry} #{value.to_s.size} #{token}#{noreply}\r\n#{value}\r\n"
 
       with_socket_management(server) do |socket|
         socket.write command
+        break nil if @no_reply
         result = socket.gets
         raise_on_error_response! result
 
@@ -311,17 +410,79 @@ class MemCache
   # If +raw+ is true, +value+ will not be Marshalled.
   #
   # Readers should call this method in the event of a cache miss, not
-  # MemCache#set or MemCache#[]=.
+  # MemCache#set.
 
   def add(key, value, expiry = 0, raw = false)
     raise MemCacheError, "Update of readonly cache" if @readonly
+    value = Marshal.dump value unless raw
+    with_server(key) do |server, cache_key|
+      logger.debug { "add #{key} to #{server}: #{value ? value.to_s.size : 'nil'}" } if logger
+      command = "add #{cache_key} 0 #{expiry} #{value.to_s.size}#{noreply}\r\n#{value}\r\n"
+
+      with_socket_management(server) do |socket|
+        socket.write command
+        break nil if @no_reply
+        result = socket.gets
+        raise_on_error_response! result
+        result
+      end
+    end
+  end
+  
+  ##
+  # Add +key+ to the cache with value +value+ that expires in +expiry+
+  # seconds, but only if +key+ already exists in the cache.
+  # If +raw+ is true, +value+ will not be Marshalled.
+  def replace(key, value, expiry = 0, raw = false)
+    raise MemCacheError, "Update of readonly cache" if @readonly
+    value = Marshal.dump value unless raw
+    with_server(key) do |server, cache_key|
+      logger.debug { "replace #{key} to #{server}: #{value ? value.to_s.size : 'nil'}" } if logger
+      command = "replace #{cache_key} 0 #{expiry} #{value.to_s.size}#{noreply}\r\n#{value}\r\n"
+
+      with_socket_management(server) do |socket|
+        socket.write command
+        break nil if @no_reply
+        result = socket.gets
+        raise_on_error_response! result
+        result
+      end
+    end
+  end
+
+  ##
+  # Append - 'add this data to an existing key after existing data'
+  # Please note the value is always passed to memcached as raw since it
+  # doesn't make a lot of sense to concatenate marshalled data together.
+  def append(key, value)
+    raise MemCacheError, "Update of readonly cache" if @readonly
     with_server(key) do |server, cache_key|
-      value = Marshal.dump value unless raw
-      logger.debug { "ADD #{key} to #{server}: #{value ? value.to_s.size : 'nil'}" } if logger
-      command = "add #{cache_key} 0 #{expiry} #{value.to_s.size}\r\n#{value}\r\n"
+      logger.debug { "append #{key} to #{server}: #{value ? value.to_s.size : 'nil'}" } if logger
+      command = "append #{cache_key} 0 0 #{value.to_s.size}#{noreply}\r\n#{value}\r\n"
 
       with_socket_management(server) do |socket|
         socket.write command
+        break nil if @no_reply
+        result = socket.gets
+        raise_on_error_response! result
+        result
+      end
+    end
+  end
+
+  ##
+  # Prepend - 'add this data to an existing key before existing data'
+  # Please note the value is always passed to memcached as raw since it
+  # doesn't make a lot of sense to concatenate marshalled data together.
+  def prepend(key, value)
+    raise MemCacheError, "Update of readonly cache" if @readonly
+    with_server(key) do |server, cache_key|
+      logger.debug { "prepend #{key} to #{server}: #{value ? value.to_s.size : 'nil'}" } if logger
+      command = "prepend #{cache_key} 0 0 #{value.to_s.size}#{noreply}\r\n#{value}\r\n"
+
+      with_socket_management(server) do |socket|
+        socket.write command
+        break nil if @no_reply
         result = socket.gets
         raise_on_error_response! result
         result
@@ -336,7 +497,9 @@ class MemCache
     raise MemCacheError, "Update of readonly cache" if @readonly
     with_server(key) do |server, cache_key|
       with_socket_management(server) do |socket|
-        socket.write "delete #{cache_key} #{expiry}\r\n"
+        logger.debug { "delete #{cache_key} on #{server}" } if logger
+        socket.write "delete #{cache_key} #{expiry}#{noreply}\r\n"
+        break nil if @no_reply
         result = socket.gets
         raise_on_error_response! result
         result
@@ -346,19 +509,33 @@ class MemCache
 
   ##
   # Flush the cache from all memcache servers.
-
-  def flush_all
+  # A non-zero value for +delay+ will ensure that the flush
+  # is propogated slowly through your memcached server farm.
+  # The Nth server will be flushed N*delay seconds from now,
+  # asynchronously so this method returns quickly.
+  # This prevents a huge database spike due to a total
+  # flush all at once.
+
+  def flush_all(delay=0)
     raise MemCacheError, 'No active servers' unless active?
     raise MemCacheError, "Update of readonly cache" if @readonly
 
     begin
+      delay_time = 0
       @servers.each do |server|
         with_socket_management(server) do |socket|
-          socket.write "flush_all\r\n"
+          logger.debug { "flush_all #{delay_time} on #{server}" } if logger
+          if delay == 0 # older versions of memcached will fail silently otherwise
+            socket.write "flush_all#{noreply}\r\n"
+          else
+            socket.write "flush_all #{delay_time}#{noreply}\r\n"
+          end
+          break nil if @no_reply
           result = socket.gets
           raise_on_error_response! result
           result
         end
+        delay_time += delay
       end
     rescue IndexError => err
       handle_error nil, err
@@ -466,10 +643,14 @@ class MemCache
   # requested.
 
   def make_cache_key(key)
+    if @autofix_keys and (key =~ /\s/ or (key.length + (namespace.nil? ? 0 : namespace.length)) > 250)
+      key = "#{Digest::SHA1.hexdigest(key)}-autofixed"
+    end
+
     if namespace.nil? then
       key
     else
-      "#{@namespace}:#{key}"
+      "#{@namespace}#{@namespace_separator}#{key}"
     end
   end
 
@@ -500,7 +681,7 @@ class MemCache
       break unless failover
       hkey = hash_for "#{try}#{key}"
     end
-
+    
     raise MemCacheError, "No servers available"
   end
 
@@ -510,7 +691,8 @@ class MemCache
 
   def cache_decr(server, cache_key, amount)
     with_socket_management(server) do |socket|
-      socket.write "decr #{cache_key} #{amount}\r\n"
+      socket.write "decr #{cache_key} #{amount}#{noreply}\r\n"
+      break nil if @no_reply
       text = socket.gets
       raise_on_error_response! text
       return nil if text == "NOT_FOUND\r\n"
@@ -546,6 +728,38 @@ class MemCache
     end
   end
 
+  def gets(key, raw = false)
+    with_server(key) do |server, cache_key|
+      logger.debug { "gets #{key} from #{server.inspect}" } if logger
+      result = with_socket_management(server) do |socket|
+        socket.write "gets #{cache_key}\r\n"
+        keyline = socket.gets # "VALUE <key> <flags> <bytes> <cas token>\r\n"
+
+        if keyline.nil? then
+          server.close
+          raise MemCacheError, "lost connection to #{server.host}:#{server.port}"
+        end
+
+        raise_on_error_response! keyline
+        return nil if keyline == "END\r\n"
+
+        unless keyline =~ /(\d+) (\w+)\r/ then
+          server.close
+          raise MemCacheError, "unexpected response #{keyline.inspect}"
+        end
+        value = socket.read $1.to_i
+        socket.read 2 # "\r\n"
+        socket.gets   # "END\r\n"
+        [value, $2]
+      end
+      result[0] = Marshal.load result[0] unless raw
+      result
+    end
+  rescue TypeError => err
+    handle_error nil, err
+  end
+
+
   ##
   # Fetches +cache_keys+ from +server+ using a multi-get.
 
@@ -579,7 +793,8 @@ class MemCache
 
   def cache_incr(server, cache_key, amount)
     with_socket_management(server) do |socket|
-      socket.write "incr #{cache_key} #{amount}\r\n"
+      socket.write "incr #{cache_key} #{amount}#{noreply}\r\n"
+      break nil if @no_reply
       text = socket.gets
       raise_on_error_response! text
       return nil if text == "NOT_FOUND\r\n"
@@ -617,7 +832,7 @@ class MemCache
 
       block.call(socket)
 
-    rescue SocketError => err
+    rescue SocketError, Errno::EAGAIN, Timeout::Error => err
       logger.warn { "Socket failure: #{err.message}" } if logger
       server.mark_dead(err)
       handle_error(server, err)
@@ -659,6 +874,10 @@ class MemCache
     raise new_error
   end
 
+  def noreply
+    @no_reply ? ' noreply' : ''
+  end
+
   ##
   # Performs setup for making a request with +key+ from memcached.  Returns
   # the server to fetch the key from and the complete key to use.
@@ -713,13 +932,6 @@ class MemCache
   class Server
 
     ##
-    # The amount of time to wait to establish a connection with a memcached
-    # server.  If a connection cannot be established within this time limit,
-    # the server will be marked as down.
-
-    CONNECT_TIMEOUT = 0.25
-
-    ##
     # The amount of time to wait before attempting to re-establish a
     # connection with a server that is marked dead.
 
@@ -802,14 +1014,11 @@ class MemCache
 
       # Attempt to connect if not already connected.
       begin
-        @sock = @timeout ? TCPTimeoutSocket.new(@host, @port, @timeout) : TCPSocket.new(@host, @port)
-
-        if Socket.constants.include? 'TCP_NODELAY' then
-          @sock.setsockopt Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1
-        end
+        @sock = connect_to(@host, @port, @timeout)
+        @sock.setsockopt Socket::IPPROTO_TCP, Socket::TCP_NODELAY, 1
         @retry  = nil
         @status = 'CONNECTED'
-      rescue SocketError, SystemCallError, IOError, Timeout::Error => err
+      rescue SocketError, SystemCallError, IOError => err
         logger.warn { "Unable to open socket: #{err.class.name}, #{err.message}" } if logger
         mark_dead err
       end
@@ -817,6 +1026,12 @@ class MemCache
       return @sock
     end
 
+    def connect_to(host, port, timeout=nil)
+      io = MemCache::BufferedIO.new(TCPSocket.new(host, port))
+      io.read_timeout = timeout
+      io
+    end
+
     ##
     # Close the connection to the memcached server targeted by this
     # object.  The server is not considered dead.
@@ -848,51 +1063,33 @@ class MemCache
 
   class MemCacheError < RuntimeError; end
 
-end
-
-# TCPSocket facade class which implements timeouts.
-class TCPTimeoutSocket
-
-  def initialize(host, port, timeout)
-    Timeout::timeout(MemCache::Server::CONNECT_TIMEOUT, SocketError) do
-      @sock = TCPSocket.new(host, port)
-      @len = timeout
-    end
-  end
-
-  def write(*args)
-    Timeout::timeout(@len, SocketError) do
-      @sock.write(*args)
+  class BufferedIO < Net::BufferedIO # :nodoc:
+    BUFSIZE = 1024 * 16
+
+    if RUBY_VERSION < '1.9.1'
+      def rbuf_fill
+        begin
+          @rbuf << @io.read_nonblock(BUFSIZE)
+        rescue Errno::EWOULDBLOCK
+          retry unless @read_timeout
+          if IO.select([@io], nil, nil, @read_timeout)
+            retry
+          else
+            raise Timeout::Error, 'IO timeout'
+          end
+        end
+      end
     end
-  end
 
-  def gets(*args)
-    Timeout::timeout(@len, SocketError) do
-      @sock.gets(*args)
+    def setsockopt(*args)
+      @io.setsockopt(*args)
     end
-  end
 
-  def read(*args)
-    Timeout::timeout(@len, SocketError) do
-      @sock.read(*args)
+    def gets
+      readuntil("\n")
     end
   end
 
-  def _socket
-    @sock
-  end
-
-  def method_missing(meth, *args)
-    @sock.__send__(meth, *args)
-  end
-
-  def closed?
-    @sock.closed?
-  end
-
-  def close
-    @sock.close
-  end
 end
 
 module Continuum
@@ -932,4 +1129,6 @@ module Continuum
       "<#{value}, #{server.host}:#{server.port}>"
     end
   end
+
 end
+require 'continuum_native'
\ No newline at end of file