我也碰到这个问题了，还在折腾中

折腾了一下午，这个问题终于解决了。用了很恶心的排除法，发现其中一个 product.description 里面有个 ^K 字符（终端里面可以按 ctrl-v-k 打出来), 把这个字符删除掉 reindex 就没问题了！

#2 楼 @ryancheung 我最开始的方案是找到这个字符，然后直接在数据库里面删除掉。不过后来提交了个缺陷给 sunspot 项目组，有人回复了，解决方案如下： 直接修改 Data Extractor，不过是非官方的。。。。。。

module Sunspot
  # 
  # DataExtractors present an internal API for the indexer to use to extract
  # field values from models for indexing. They must implement the #value_for
  # method, which takes an object and returns the value extracted from it.
  #
  module DataExtractor #:nodoc: all
    # 
    # AttributeExtractors extract data by simply calling a method on the block.
    #
    class AttributeExtractor
      def initialize(attribute_name)
        @attribute_name = attribute_name
      end

      def value_for(object)
        Filter.new( object.send(@attribute_name) ).value
      end
    end

    # 
    # BlockExtractors extract data by evaluating a block in the context of the
    # object instance, or if the block takes an argument, by passing the object
    # as the argument to the block. Either way, the return value of the block is
    # the value returned by the extractor.
    #
    class BlockExtractor
      def initialize(&block)
        @block = block
      end

      def value_for(object)
        Filter.new( Util.instance_eval_or_call(object, &@block) ).value
      end
    end

    # 
    # Constant data extractors simply return the same value for every object.
    #
    class Constant
      def initialize(value)
        @value = value
      end

      def value_for(object)
        Filter.new(@value).value
      end
    end

    # 
    # A Filter to allow easy value cleaning
    #
    class Filter
      def initialize(value)
        @value = value
      end
      def value
        strip_control_characters @value
      end
      def strip_control_characters(value)
        return value unless value.is_a? String

        value.chars.inject("") do |str, char|
          unless char.ascii_only? and (char.ord < 32 or char.ord == 127)
            str << char
          end
          str
        end

      end
    end

  end
end

@kingguy :plus1: