Class: TokyoCacheCow::Server

Inherits:
EventMachine::Connection
  • Object
show all
Defined in:
lib/tokyo_cache_cow/server.rb

Constant Summary collapse

Terminator = 
"\r\n"
SetCommand =

set

/(\S+) +(\d+) +(\d+) +(\d+)( +noreply)?/
CasCommand = 
/(\S+) +(\d+) +(\d+) +(\d+) +(\d+)( +noreply)?/
StoredReply = 
"STORED\r\n"
NotStoredReply = 
"NOT_STORED\r\n"
ExistsReply = 
"EXISTS\r\n"
NotFoundReply = 
"NOT_FOUND\r\n"
GetValueReply = 
"VALUE %s %d %d\r\n"
CasValueReply = 
"VALUE %d %d %d %d\r\n"
EndReply = 
"END\r\n"
DeleteCommand =

delete

/(\S+) *(noreply)?/
DeleteWithTimeoutCommand = 
/(\S+) +(\d+) *(noreply)?/
DeletedReply = 
"DELETED\r\n"
NotDeletedReply = 
"NOT_DELETED\r\n"
DeleteMatchCommand =

delete_match

/(\S+)( +noreply)?/
IncrementDecrementCommand =

Increment/Decrement

/(\S+) +(\d+)( +noreply)?/
ValueReply = 
"%d\r\n"
OK =

errors

"OK\r\n"
Error = 
"ERROR\r\n"
ClientError = 
"CLIENT_ERROR %s\r\n"
ServerError = 
"SERVER_ERROR %s\r\n"
TerminatorRegex = 
/\r\n/

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#cache ⇒ Object

Returns the value of attribute cache.



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# File 'lib/tokyo_cache_cow/server.rb', line 45

def cache
  @cache
end

Instance Method Details

#receive_data(data) ⇒ Object 



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# File 'lib/tokyo_cache_cow/server.rb', line 69

def receive_data(data)
  ss = StringScanner.new(data)
  
  while part = ss.scan_until(TerminatorRegex)
    begin
      command_argument_separator_index = part.index(/\s/)
      command = part[0, command_argument_separator_index]
      args = part[command_argument_separator_index + 1, part.size - command_argument_separator_index - 3]
      case command
      when 'get', 'gets'
        keys = args.split(/\s+/)
        keys.each do |k|
          next unless validate_key(k)
          if data = @cache.get(k)
            if command == 'get'
              send_data(GetValueReply % [k, data[:flags], data[:value].size])
            else
              send_data(CasValueReply % [k, data[:flags], data[:value].size, data[:value].hash])
            end
            send_data(data[:value])
            send_data(Terminator)
          end
        end
        send_data(EndReply)
      when 'set'
        SetCommand.match(args) or (send_client_error and next)
        (key, flags, expires, bytes, noreply) = [$1, Integer($2), Integer($3), Integer($4), !$5.nil?]
        next unless validate_key(key)
        send_data(@cache.set(key, ss.rest[0, bytes.to_i], :flags => flags, :expires => expires) ?
          StoredReply : NotStoredReply)
        ss.pos += bytes + 2 
      when 'add'
        SetCommand.match(args)
        (key, flags, expires, bytes, noreply) = [$1, $2.to_i, $3.to_i, $4, !$5.nil?]
        send_data(@cache.add(key, ss.rest[0, bytes.to_i], :flags => flags, :expires => expires) ?
          StoredReply : NotStoredReply)
        ss.pos += bytes + 2 
      when 'replace'
        SetCommand.match(args)
        (key, flags, expires, bytes, noreply) = [$1, $2.to_i, $3.to_i, $4, !$5.nil?]
        send_data(@cache.replace(key, ss.rest[0, bytes.to_i], :flags => flags, :expires => expires) ?
          StoredReply : NotStoredReply)
        ss.pos += bytes + 2 
      when 'append'
        SetCommand.match(args)
        (key, flags, expires, bytes, noreply) = [$1, $2.to_i, $3.to_i, $4, !$5.nil?]
        send_data(@cache.append(key, ss.rest[0, bytes.to_i], :flags => flags, :expires => expires) ?
          StoredReply : NotStoredReply)
        ss.pos += bytes + 2 
      when 'prepend'
        SetCommand.match(args)
        (key, flags, expires, bytes, noreply) = [$1, $2.to_i, $3.to_i, $4, !$5.nil?]
        send_data(@cache.prepend(key, ss.rest[0, bytes.to_i], :flags => flags, :expires => expires) ?
          StoredReply : NotStoredReply)
        ss.pos += bytes + 2 
      when 'cas'
        # do something
      when 'delete'
        case args
        when DeleteWithTimeoutCommand
          (key, timeout, noreply) = [$1.chomp, $2, !$3.nil?]
          next unless validate_key(key)
          send_data(@cache.delete_expire(key, timeout) ?
            DeletedReply : NotDeletedReply)
        when DeleteCommand
          (key, noreply) = [$1.chomp, !$2.nil?]
          next unless validate_key(key)
          send_data @cache.delete(key) ?
            DeletedReply : NotDeletedReply
        end
      when 'delete_match'
        DeleteMatchCommand.match(args)
        (key, noreply) = [$1.chomp, !$2.nil?]
        next unless validate_key(key)
        @cache.delete_match(key)
        send_data(DeletedReply)
      when 'incr', 'decr'
        IncrementDecrementCommand.match(args)
        (key, value, noreply) = [$1, $2.to_i, !$3.nil?]
        next unless validate_key(key)
        send_data(if d = @cache.get(key)
          value = -value if command == 'decr'
          d['data'] = (val = (d['data'].to_i + value)).to_s
          @cache.put(key, d)
          ValueReply % val
        else
          NotFoundReply
        end)
      when 'stats'
        send_data(Error)
      when 'flush_all'
        send_data(@cache.flush_all ? OK : Error)
      when 'version'
        send_data(Error)
      when 'quit'
        close_connection_after_writing
      else
        send_data(Error)
      end
    rescue
      send_server_error($!)
    end
  end
  
end

#send_client_error(message = "invalid arguments") ⇒ Object 



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# File 'lib/tokyo_cache_cow/server.rb', line 47

def send_client_error(message = "invalid arguments")
  send_data(ClientError % message.to_s)
end

#send_server_error(message = "there was a problem") ⇒ Object 



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# File 'lib/tokyo_cache_cow/server.rb', line 51

def send_server_error(message = "there was a problem")
  send_data(ServerError % message.to_s)
end

#validate_key(key) ⇒ Object 



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# File 'lib/tokyo_cache_cow/server.rb', line 55

def validate_key(key)
  if key.nil?
    send_data(ClientError % "key cannot be blank")
  elsif key && key.index(' ')
    send_data(ClientError % "key cannot contain spaces")
    nil
  elsif key.size > 250
    send_data(ClientError % "key must be less than 250 characters")
    nil
  else
    key
  end
end