seo and breadcrumbs defined demo base on bbtang.com

application.html.erb

  <% if title = get_seo_info("title") %>
    <title><%= "#{title} #{ @default_title}" %></title>
  <% else %>
    <title><%= "#{ @default_title}" %></title>
  <% end %>

  <% if keywords = get_seo_info("keywords") %>
    <meta name="keywords" content="<%= keywords %>">
  <% else %>
    <meta name="keywords" content="<%= Askjane::MetaCache.get_config_data("default_meta_keywords") %>" />
  <% end %>

  <% if description = get_seo_info("description") %>
    <meta name="description" content="<%= description %>" />
  <% else %>
    <meta name="description" content="<%= Askjane::MetaCache.get_config_data("default_meta_description") %>" />
  <% end %>

application.rb

# encoding: utf-8
class ApplicationController < ActionController::Base

  before_filter :add_initial_breadcrumbs
  before_filter :add_model_breadcrumbs
  before_filter :set_seo_meta

  def set_seo_meta(title = '',meta_keywords = '', meta_description = '')
    g_obj = guessed_object
    if g_obj.present?
      [:title, :name, :nickname].each do |col|
        #@meta_title = g_obj.send col  if g_obj.respond_to? col
        if (g_obj.respond_to? col)
          translations = I18n.backend.send(:translations)
          if translations[:"zh-CN"][:helpers][:titles]["#{params[:action]}".to_sym].present?
            @meta_title = I18n.t("helpers.titles.#{params[:action]}",:model => (g_obj.send col))
          else
            @meta_title = g_obj.send col
          end
        end
      end

      @meta_keywords = g_obj.tag_list.join(",") if g_obj.respond_to? :tag_list
      @meta_description = g_obj.summary if g_obj.respond_to? :summary
      @meta_description = g_obj.description if g_obj.respond_to? :description
    end

    if title.present?
      @meta_title = "#{title}"
    end

    @meta_keywords = meta_keywords if meta_keywords.present?
    @meta_description = meta_description if meta_description.present?

  end

  def guessed_object
    @model_class = params[:controller].classify.constantize if params[:controller].classify.class_exists?
    @model_class = params[:controller].gsub(/\w+([\/]+)/,"").classify.constantize if params[:controller].gsub(/\w+([\/]+)/,"").classify.class_exists?

    if @model_class.present?
      @model_class.where(id: params[:id]).first if params[:id].present?
      #guessed_instance_variable_name = "@#{@model_class.name.singularize.downcase}"
      #if self.instance_variable_defined? guessed_instance_variable_name
      #  self.instance_variable_get guessed_instance_variable_name
      #end
    end
  end

  def add_initial_breadcrumbs
    breadcrumbs.add :home, root_path
  end

  def add_model_breadcrumbs

    model_class = params[:controller].gsub(/\w+([\/]+)/,"").classify.constantize if params[:controller].gsub(/\w+([\/]+)/,"").classify.class_exists?
    if model_class.present?
      controller = params[:controller].gsub('/','_') if params[:controller].present?

      if model_class.model_name.singularize.eql? model_class.model_name.pluralize
        controller += "_index" if params[:controller].present?
      end
      route_name = "#{controller}_path"
      breadcrumbs.add I18n.t("mod.#{controller}",opt = {}), self.send(route_name) if self.respond_to? route_name
    end
  end
end

application_helper.rb

# encoding: utf-8
module ApplicationHelper

  # 获取seo配置
  def get_seo_info(type_name)
    @default_title = "#{breadcrumbs.items.collect{|item| item.first}.reverse.join('_')}".gsub("_首页","|#{Setting.app_name}")
    @default_title = "|#{Setting.app_name}" if @default_title.eql? "首页"
    name = @controller.to_s.downcase + "#" + @action.to_s.downcase
    if seo = Rails.configuration.self_settings["seos"][name]
      seo = JSON.parse(seo)
      return seo[type_name]
    else
      return self.instance_variable_get "@meta_#{type_name}"
    end
  end
end

breadcrumbs.yml

# encoding: utf-8
"zh-CN":
  mod:
    albums: "相册"
    answers: "回答"
    knowledges: "自学当妈"
    questions: "有问有答"
    photos: "照片"
    subjects: "专题"
    topics: "主题"
    people: "个人主页"
    notes: "个人日志"
    profiles: "个人资料"
  breadcrumbs:
    home: "首页"
    registration: "注册"
    searchs: "搜索"
    tag: "标签"
    first: "First"
    second: "Second"
    third: "Third"
    people:
      show: "%{user}的个人主页"
      knowledges: "%{user}的个人收藏"
      questions: "%{user}的问答"
      followings: "%{user}关注的人"
      followers: "%{user}的粉丝"
      mycomments: "关于%{user}的评论"
      add_comm: "为%{user}添加留言"
      designateds: "%{user}的邀请回答"
    notes:
      index: "%{user}的日志"
      new: "新增日志"
      show: "浏览%{note}"
    albums:
      index: "%{user}的个人相册"
    photos:
      new: "添加照片"
      show: "浏览%{photo}"