anchor.diff:  -export([content_types_accepted/2]).
   -export([read_json/2]).
   -export([write_json/2]).
  +-export([delete_resource/2]).
   
   -record(state, {path, segments, hash}).
   
  
positive.code:     Q = <<"update objects set version=version+1,value=value||hstore($2::text[]) where hash=$1">>,
      {ok, _} = cloudstore_pg:equery(cloudstore_pool, Q, [Hash, HProps]),
      {true, Req0, State}.
  
negative.code:     {false, Req0, State#state{path = Path, segments = Segments}}.
  
  allowed_methods(Req, State) ->
      {[<<"GET">>, <<"PUT">>, <<"DELETE">>], Req, State}.
  
  resource_exists(Req, #state{path = Path} = State) ->
      Q = <<"select hash from objects where hash=md5($1)">>,
  