Erl Mongo snippets

gistfile1.txt

find_probe:
===========

handle_call({find_probe, ProbeId}, _From, State) ->                                       
  {_Sup, {Mongo, _Redis}} = State,                                                        
  ProbeOid = binary_string_to_objectid(ProbeId),                                          
  {R} = mongo:find_one(Mongo, <<"nodes">>, {'probes._id', ProbeOid}),                     
                                                                                          
  [Res|_] = lists:filter(fun(V) -> bson:at('_id', V) == ProbeOid end, bson:at(probes, R)),
  {reply, Res, State};                                                                    

binary_string_to_objectid(BinaryString) ->                                  
  binary_string_to_objectid(BinaryString, []).                              
binary_string_to_objectid(<<>>, Result) ->                                  
  {list_to_binary(lists:reverse(Result))};                                  
binary_string_to_objectid(<<BS:2/binary, Bin/binary>>, Result) ->           
  binary_string_to_objectid(Bin, [erlang:binary_to_integer(BS, 16)|Result]).