Traces queries to mysql and pgsql

boss_tracer.erl

-module (boss_tracer).

-behaviour (gen_server).

-export([start/0]).

%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
   terminate/2, code_change/3]).

-define(SERVER, ?MODULE). 

start()->
  gen_server:start({local, ?SERVER}, ?MODULE, [], []).


init([])->
  Tracer = erlang:trace(all, true, [call]),
  erlang:trace_pattern({pgsql, equery, '_'}, true, [local]),
  erlang:trace_pattern({mysql_conn, fetch, '_'}, true, [local]),
  error_logger:info_msg("Started ~p~n", [Tracer]),
  {ok, ""}.

handle_call(Msg, _From, State)->
  {reply, ok, State}.

handle_cast(Msg, State) ->
  {noreply, State}.

handle_info({trace_ts, Pid, call, {M, F, [Conn, Query, Params]}, Time}, State) ->
  error_logger:info_msg("~s params: ~p", [Query, Params]),
  {noreply, State};
  
handle_info(Msg, State) ->
  {noreply, State}.

terminate(_Reason, _State)->
  ok.

code_change(_OldVsn, State, _Extra) ->
    {ok, State}.