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-rw-r--r--lib/kernel/src/logger_server.erl532
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diff --git a/lib/kernel/src/logger_server.erl b/lib/kernel/src/logger_server.erl
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+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017-2018. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%% http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+-module(logger_server).
+
+-behaviour(gen_server).
+
+%% API
+-export([start_link/0,
+ add_handler/3, remove_handler/1,
+ add_filter/2, remove_filter/2,
+ set_module_level/2, unset_module_level/0,
+ unset_module_level/1, cache_module_level/1,
+ set_config/2, set_config/3, update_config/2,
+ update_formatter_config/2]).
+
+%% gen_server callbacks
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2,
+ terminate/2]).
+
+-include("logger_internal.hrl").
+
+-define(SERVER, logger).
+-define(LOGGER_SERVER_TAG, '$logger_cb_process').
+
+-record(state, {tid, async_req, async_req_queue}).
+
+%%%===================================================================
+%%% API
+%%%===================================================================
+
+start_link() ->
+ gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
+
+add_handler(Id,Module,Config0) ->
+ try {check_id(Id),check_mod(Module)} of
+ {ok,ok} ->
+ case sanity_check(Id,Config0) of
+ ok ->
+ Default = default_config(Id,Module),
+ Config = maps:merge(Default,Config0),
+ call({add_handler,Id,Module,Config});
+ Error ->
+ Error
+ end
+ catch throw:Error ->
+ {error,Error}
+ end.
+
+remove_handler(HandlerId) ->
+ call({remove_handler,HandlerId}).
+
+add_filter(Owner,Filter) ->
+ case sanity_check(Owner,filters,[Filter]) of
+ ok -> call({add_filter,Owner,Filter});
+ Error -> Error
+ end.
+
+remove_filter(Owner,FilterId) ->
+ call({remove_filter,Owner,FilterId}).
+
+set_module_level(Modules,Level) when is_list(Modules) ->
+ case lists:all(fun(M) -> is_atom(M) end,Modules) of
+ true ->
+ case sanity_check(primary,level,Level) of
+ ok -> call({set_module_level,Modules,Level});
+ Error -> Error
+ end;
+ false ->
+ {error,{not_a_list_of_modles,Modules}}
+ end;
+set_module_level(Modules,_) ->
+ {error,{not_a_list_of_modules,Modules}}.
+
+unset_module_level() ->
+ call({unset_module_level,all}).
+
+unset_module_level(Modules) when is_list(Modules) ->
+ case lists:all(fun(M) -> is_atom(M) end,Modules) of
+ true ->
+ call({unset_module_level,Modules});
+ false ->
+ {error,{not_a_list_of_modles,Modules}}
+ end;
+unset_module_level(Modules) ->
+ {error,{not_a_list_of_modules,Modules}}.
+
+cache_module_level(Module) ->
+ gen_server:cast(?SERVER,{cache_module_level,Module}).
+
+set_config(Owner,Key,Value) ->
+ update_config(Owner,#{Key=>Value}).
+
+set_config(Owner,Config) ->
+ case sanity_check(Owner,Config) of
+ ok ->
+ call({set_config,Owner,Config});
+ Error ->
+ Error
+ end.
+
+update_config(Owner, Config) ->
+ case sanity_check(Owner,Config) of
+ ok ->
+ call({update_config,Owner,Config});
+ Error ->
+ Error
+ end.
+
+update_formatter_config(HandlerId, FormatterConfig)
+ when is_map(FormatterConfig) ->
+ call({update_formatter_config,HandlerId,FormatterConfig});
+update_formatter_config(_HandlerId, FormatterConfig) ->
+ {error,{invalid_formatter_config,FormatterConfig}}.
+
+
+%%%===================================================================
+%%% gen_server callbacks
+%%%===================================================================
+
+init([]) ->
+ process_flag(trap_exit, true),
+ put(?LOGGER_SERVER_TAG,true),
+ Tid = logger_config:new(?LOGGER_TABLE),
+ PrimaryConfig = maps:merge(default_config(primary),
+ #{handlers=>[simple]}),
+ logger_config:create(Tid,primary,PrimaryConfig),
+ SimpleConfig0 = maps:merge(default_config(simple,logger_simple_h),
+ #{filter_default=>stop,
+ filters=>?DEFAULT_HANDLER_FILTERS}),
+ %% If this fails, then the node should crash
+ {ok,SimpleConfig} = logger_simple_h:adding_handler(SimpleConfig0),
+ logger_config:create(Tid,simple,logger_simple_h,SimpleConfig),
+ {ok, #state{tid=Tid, async_req_queue = queue:new()}}.
+
+handle_call({add_handler,Id,Module,HConfig}, From, #state{tid=Tid}=State) ->
+ case logger_config:exist(Tid,Id) of
+ true ->
+ {reply,{error,{already_exist,Id}},State};
+ false ->
+ call_h_async(
+ fun() ->
+ %% inform the handler
+ call_h(Module,adding_handler,[HConfig],{ok,HConfig})
+ end,
+ fun({ok,HConfig1}) ->
+ %% We know that the call_h would have loaded the module
+ %% if it existed, so it is safe here to call function_exported
+ %% to find out if this is a valid handler
+ case erlang:function_exported(Module, log, 2) of
+ true ->
+ logger_config:create(Tid,Id,Module,HConfig1),
+ {ok,Config} = do_get_config(Tid,primary),
+ Handlers = maps:get(handlers,Config,[]),
+ do_set_config(Tid,primary,
+ Config#{handlers=>[Id|Handlers]});
+ false ->
+ {error,{invalid_handler,
+ {function_not_exported,
+ {Module,log,2}}}}
+ end;
+ ({error,HReason}) ->
+ {error,{handler_not_added,HReason}}
+ end,From,State)
+ end;
+handle_call({remove_handler,HandlerId}, From, #state{tid=Tid}=State) ->
+ case logger_config:get(Tid,HandlerId) of
+ {ok,{Module,HConfig}} ->
+ {ok,Config} = do_get_config(Tid,primary),
+ Handlers0 = maps:get(handlers,Config,[]),
+ Handlers = lists:delete(HandlerId,Handlers0),
+ call_h_async(
+ fun() ->
+ %% inform the handler
+ call_h(Module,removing_handler,[HConfig],ok)
+ end,
+ fun(_Res) ->
+ do_set_config(Tid,primary,Config#{handlers=>Handlers}),
+ logger_config:delete(Tid,HandlerId),
+ ok
+ end,From,State);
+ _ ->
+ {reply,{error,{not_found,HandlerId}},State}
+ end;
+handle_call({add_filter,Id,Filter}, _From,#state{tid=Tid}=State) ->
+ Reply = do_add_filter(Tid,Id,Filter),
+ {reply,Reply,State};
+handle_call({remove_filter,Id,FilterId}, _From, #state{tid=Tid}=State) ->
+ Reply = do_remove_filter(Tid,Id,FilterId),
+ {reply,Reply,State};
+handle_call({update_config,Id,NewConfig}, From, #state{tid=Tid}=State) ->
+ case logger_config:get(Tid,Id) of
+ {ok,{_Module,OldConfig}} ->
+ Config = maps:merge(OldConfig,NewConfig),
+ handle_call({set_config,Id,Config}, From, State);
+ {ok,OldConfig} ->
+ Config = maps:merge(OldConfig,NewConfig),
+ {reply,do_set_config(Tid,Id,Config),State};
+ Error ->
+ {reply,Error,State}
+ end;
+handle_call({set_config,primary,Config0}, _From, #state{tid=Tid}=State) ->
+ Config = maps:merge(default_config(primary),Config0),
+ {ok,#{handlers:=Handlers}} = logger_config:get(Tid,primary),
+ Reply = do_set_config(Tid,primary,Config#{handlers=>Handlers}),
+ {reply,Reply,State};
+handle_call({set_config,HandlerId,Config0}, From, #state{tid=Tid}=State) ->
+ case logger_config:get(Tid,HandlerId) of
+ {ok,{Module,OldConfig}} ->
+ Config = maps:merge(default_config(HandlerId,Module),Config0),
+ call_h_async(
+ fun() ->
+ call_h(Module,changing_config,[OldConfig,Config],
+ {ok,Config})
+ end,
+ fun({ok,Config1}) ->
+ do_set_config(Tid,HandlerId,Config1);
+ (Error) ->
+ Error
+ end,From,State);
+ _ ->
+ {reply,{error,{not_found,HandlerId}},State}
+ end;
+handle_call({update_formatter_config,HandlerId,NewFConfig},_From,
+ #state{tid=Tid}=State) ->
+ Reply =
+ case logger_config:get(Tid,HandlerId) of
+ {ok,{_Mod,#{formatter:={FMod,OldFConfig}}=Config}} ->
+ try
+ FConfig = maps:merge(OldFConfig,NewFConfig),
+ check_formatter({FMod,FConfig}),
+ do_set_config(Tid,HandlerId,
+ Config#{formatter=>{FMod,FConfig}})
+ catch throw:Reason -> {error,Reason}
+ end;
+ _ ->
+ {error,{not_found,HandlerId}}
+ end,
+ {reply,Reply,State};
+handle_call({set_module_level,Modules,Level}, _From, #state{tid=Tid}=State) ->
+ Reply = logger_config:set_module_level(Tid,Modules,Level),
+ {reply,Reply,State};
+handle_call({unset_module_level,Modules}, _From, #state{tid=Tid}=State) ->
+ Reply = logger_config:unset_module_level(Tid,Modules),
+ {reply,Reply,State}.
+
+handle_cast({async_req_reply,_Ref,_Reply} = Reply,State) ->
+ call_h_reply(Reply,State);
+handle_cast({cache_module_level,Module}, #state{tid=Tid}=State) ->
+ logger_config:cache_module_level(Tid,Module),
+ {noreply, State}.
+
+%% Interface for those who can't call the API - e.g. the emulator, or
+%% places related to code loading.
+%%
+%% This can also be log events from remote nodes which are sent from
+%% logger.erl when the group leader of the client process is on a
+%% same node as the client process itself.
+handle_info({log,Level,Format,Args,Meta}, State) ->
+ logger:log(Level,Format,Args,Meta),
+ {noreply, State};
+handle_info({log,Level,Report,Meta}, State) ->
+ logger:log(Level,Report,Meta),
+ {noreply, State};
+handle_info({Ref,_Reply},State) when is_reference(Ref) ->
+ %% Assuming this is a timed-out gen_server reply - ignoring
+ {noreply, State};
+handle_info({'DOWN',_Ref,_Proc,_Pid,_Reason} = Down,State) ->
+ call_h_reply(Down,State);
+handle_info(Unexpected,State) when element(1,Unexpected) == 'EXIT' ->
+ %% The simple handler will send an 'EXIT' message when it is replaced
+ %% We may as well ignore all 'EXIT' messages that we get
+ ?LOG_INTERNAL(debug,
+ [{logger,got_unexpected_message},
+ {process,?SERVER},
+ {message,Unexpected}]),
+ {noreply,State};
+handle_info(Unexpected,State) ->
+ ?LOG_INTERNAL(info,
+ [{logger,got_unexpected_message},
+ {process,?SERVER},
+ {message,Unexpected}]),
+ {noreply,State}.
+
+terminate(_Reason, _State) ->
+ ok.
+
+%%%===================================================================
+%%% Internal functions
+%%%===================================================================
+call(Request) ->
+ Action = element(1,Request),
+ case get(?LOGGER_SERVER_TAG) of
+ true when
+ Action == add_handler; Action == remove_handler;
+ Action == update_config; Action == set_config ->
+ {error,{attempting_syncronous_call_to_self,Request}};
+ _ ->
+ gen_server:call(?SERVER,Request,?DEFAULT_LOGGER_CALL_TIMEOUT)
+ end.
+
+do_add_filter(Tid,Id,{FId,_} = Filter) ->
+ case do_get_config(Tid,Id) of
+ {ok,Config} ->
+ Filters = maps:get(filters,Config,[]),
+ case lists:keymember(FId,1,Filters) of
+ true ->
+ {error,{already_exist,FId}};
+ false ->
+ do_set_config(Tid,Id,Config#{filters=>[Filter|Filters]})
+ end;
+ Error ->
+ Error
+ end.
+
+do_remove_filter(Tid,Id,FilterId) ->
+ case do_get_config(Tid,Id) of
+ {ok,Config} ->
+ Filters0 = maps:get(filters,Config,[]),
+ case lists:keytake(FilterId,1,Filters0) of
+ {value,_,Filters} ->
+ do_set_config(Tid,Id,Config#{filters=>Filters});
+ false ->
+ {error,{not_found,FilterId}}
+ end;
+ Error ->
+ Error
+ end.
+
+do_get_config(Tid,Id) ->
+ case logger_config:get(Tid,Id) of
+ {ok,{_,Config}} ->
+ {ok,Config};
+ {ok,Config} ->
+ {ok,Config};
+ Error ->
+ Error
+ end.
+
+do_set_config(Tid,Id,Config) ->
+ logger_config:set(Tid,Id,Config),
+ ok.
+
+default_config(primary) ->
+ #{level=>notice,
+ filters=>[],
+ filter_default=>log};
+default_config(Id) ->
+ #{id=>Id,
+ level=>all,
+ filters=>[],
+ filter_default=>log,
+ formatter=>{?DEFAULT_FORMATTER,#{}}}.
+default_config(Id,Module) ->
+ (default_config(Id))#{module=>Module}.
+
+sanity_check(Owner,Key,Value) ->
+ sanity_check_1(Owner,[{Key,Value}]).
+
+sanity_check(HandlerId,Config) when is_map(Config) ->
+ sanity_check_1(HandlerId,maps:to_list(Config));
+sanity_check(_,Config) ->
+ {error,{invalid_handler_config,Config}}.
+
+sanity_check_1(Owner,Config) when is_list(Config) ->
+ try
+ Type = get_type(Owner),
+ check_config(Type,Config)
+ catch throw:Error -> {error,Error}
+ end.
+
+get_type(primary) ->
+ primary;
+get_type(Id) ->
+ check_id(Id),
+ handler.
+
+check_config(Owner,[{level,Level}|Config]) ->
+ check_level(Level),
+ check_config(Owner,Config);
+check_config(Owner,[{filters,Filters}|Config]) ->
+ check_filters(Filters),
+ check_config(Owner,Config);
+check_config(Owner,[{filter_default,FD}|Config]) ->
+ check_filter_default(FD),
+ check_config(Owner,Config);
+check_config(handler,[{formatter,Formatter}|Config]) ->
+ check_formatter(Formatter),
+ check_config(handler,Config);
+check_config(primary,[C|_]) ->
+ throw({invalid_primary_config,C});
+check_config(handler,[{_,_}|Config]) ->
+ %% Arbitrary config elements are allowed for handlers
+ check_config(handler,Config);
+check_config(_,[]) ->
+ ok.
+
+check_id(Id) when is_atom(Id) ->
+ ok;
+check_id(Id) ->
+ throw({invalid_id,Id}).
+
+check_mod(Mod) when is_atom(Mod) ->
+ ok;
+check_mod(Mod) ->
+ throw({invalid_module,Mod}).
+
+check_level({LevelInt,cached}) when LevelInt>=?EMERGENCY, LevelInt=<?DEBUG ->
+ ok;
+check_level(Level) ->
+ case lists:member(Level,?LEVELS) of
+ true ->
+ ok;
+ false ->
+ throw({invalid_level,Level})
+ end.
+
+check_filters([{Id,{Fun,_Args}}|Filters]) when is_atom(Id), is_function(Fun,2) ->
+ check_filters(Filters);
+check_filters([Filter|_]) ->
+ throw({invalid_filter,Filter});
+check_filters([]) ->
+ ok;
+check_filters(Filters) ->
+ throw({invalid_filters,Filters}).
+
+check_filter_default(FD) when FD==stop; FD==log ->
+ ok;
+check_filter_default(FD) ->
+ throw({invalid_filter_default,FD}).
+
+check_formatter({Mod,Config}) ->
+ check_mod(Mod),
+ try Mod:check_config(Config) of
+ ok -> ok;
+ {error,Error} -> throw(Error)
+ catch
+ C:R:S ->
+ case {C,R,S} of
+ {error,undef,[{Mod,check_config,[Config],_}|_]} ->
+ ok;
+ _ ->
+ throw({callback_crashed,
+ {C,R,logger:filter_stacktrace(?MODULE,S)}})
+ end
+ end;
+check_formatter(Formatter) ->
+ throw({invalid_formatter,Formatter}).
+
+call_h(Module, Function, Args, DefRet) ->
+ %% Not calling code:ensure_loaded + erlang:function_exported here,
+ %% since in some rare terminal cases, the code_server might not
+ %% exist and we'll get a deadlock in removing the handler.
+ try apply(Module, Function, Args)
+ catch
+ C:R:S ->
+ case {C,R,S} of
+ {error,undef,[{Module,Function,Args,_}|_]} ->
+ DefRet;
+ _ ->
+ ST = logger:filter_stacktrace(?MODULE,S),
+ ?LOG_INTERNAL(error,
+ [{logger,callback_crashed},
+ {process,?SERVER},
+ {reason,{C,R,ST}}]),
+ {error,{callback_crashed,{C,R,ST}}}
+ end
+ end.
+
+%% There are all sort of API functions that can cause deadlocks if called
+%% from the handler callbacks. So we spawn a process that does the request
+%% for the logger_server. There are still APIs that will cause problems,
+%% namely logger:add_handler
+call_h_async(AsyncFun,PostFun,From,#state{ async_req = undefined } = State) ->
+ Parent = self(),
+ {Pid, Ref} = spawn_monitor(
+ fun() ->
+ put(?LOGGER_SERVER_TAG,true),
+ receive Ref -> Ref end,
+ gen_server:cast(Parent, {async_req_reply, Ref, AsyncFun()})
+ end),
+ Pid ! Ref,
+ {noreply,State#state{ async_req = {Ref,PostFun,From} }};
+call_h_async(AsyncFun,PostFun,From,#state{ async_req_queue = Q } = State) ->
+ {noreply,State#state{ async_req_queue = queue:in({AsyncFun,PostFun,From},Q) }}.
+
+call_h_reply({async_req_reply,Ref,Reply},
+ #state{ async_req = {Ref,PostFun,From}, async_req_queue = Q} = State) ->
+ erlang:demonitor(Ref,[flush]),
+ _ = gen_server:reply(From, PostFun(Reply)),
+ {Value,NewQ} = queue:out(Q),
+ NewState = State#state{ async_req = undefined,
+ async_req_queue = NewQ },
+ case Value of
+ {value,{AsyncFun,NPostFun,NFrom}} ->
+ call_h_async(AsyncFun,NPostFun,NFrom,NewState);
+ empty ->
+ {noreply,NewState}
+ end;
+call_h_reply({'DOWN',Ref,_Proc,Pid,Reason}, #state{ async_req = {Ref,_PostFun,_From}} = State) ->
+ %% This clause should only be triggered if someone explicitly sends an exit signal
+ %% to the spawned process. It is only here to make sure that the logger_server does
+ %% not deadlock if that happens.
+ ?LOG_INTERNAL(error,
+ [{logger,process_exited},
+ {process,Pid},
+ {reason,Reason}]),
+ call_h_reply(
+ {async_req_reply,Ref,{error,{logger_process_exited,Pid,Reason}}},
+ State);
+call_h_reply(Unexpected,State) ->
+ ?LOG_INTERNAL(info,
+ [{logger,got_unexpected_message},
+ {process,?SERVER},
+ {message,Unexpected}]),
+ {noreply,State}.