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Diffstat (limited to 'lib/kernel/src/logger_server.erl')
| -rw-r--r-- | lib/kernel/src/logger_server.erl | 532 |
1 files changed, 532 insertions, 0 deletions
diff --git a/lib/kernel/src/logger_server.erl b/lib/kernel/src/logger_server.erl new file mode 100644 index 0000000000..28e31d46ea --- /dev/null +++ b/lib/kernel/src/logger_server.erl @@ -0,0 +1,532 @@ +%% +%% %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}. |