Swift3 iOS -Firebase如何将节点数据分离到不同的数组和字典中

root
  |
  @-clothing
      |
      @-nameBrandRalphLauren//topLevel
      |  |
      |  @-apparelTops//child
      |  |    |-"garmetSweater":"white"
      |  |    |-"garmetTshirt":"blue"
      |  |    |-"postedBy":"user123"
      |  |
      |  @-apparelBottoms//child
      |       |-"garmetShorts":"tan"
      |       |-"garmetJeans":"blue"
      |       |-"postedBy":"user123"
      |
      @-nameBrandNike//topLevel
         |
         @-apparelTops//child
              |-"garmetSweater":"gray"
              |-"garmetTshirt":"pink"
              |-"postedBy":"user789"
root
  |
  @-clothing
      |
      @-nameBrand