文件结构:
|--job_center_alarm.erl [gen_event通用事件处理]
|--job_center_app.erl [application回调模块]
|--job_center_supervisor.erl [supervisor监控树的应用]
|--job_center.app [application资源文件]
|--job_center.erl [gen_server构建的服务器]
1.job_center_alarm.erl [gen_event通用事件处理]
-module(job_center_alarm).
-export([init/1,handle_event/2,handle_call/2,handle_info/2,code_change/3,terminate/2]).
-behaviour(gen_event).
init(Args)->{ok,0}.
handle_event({set_alarm,What},State)->
io:format("Alarm comming:~p!~n",[What]),
{ok,State};
handle_event({clear_alarm,What},State)->
io:format("Alarm_clean:~p!~n",[What]),
{ok,State}.
handle_call(_Req,State)->
{ok,ignore,State}.
handle_info(_Info,State)->
{ok,State}.
code_change(_OldVsn,State,_Extra)->{ok,State}.
terminate(_Reason,_State)->ok.
2.job_center_app.erl [application回调模块]
-module(job_center_app).
-behaviour(application).
-export([start/2,stop/1]).
start(_Type,StartArgs)->
job_center_supervisor:start_link(StartArgs).
stop(_State)->
ok.
3.job_center_supervisor.erl [supervisor监控树的应用]
-module(job_center_supervisor).
-export([start/0,test/0,init/1,start_link/1]).
-behaviour(supervisor).
-define(MAXRESTARTS,3).
-define(TIME,10).
start()->
spawn(fun()-> supervisor:start_link({local,?MODULE},?MODULE,[]) end).
start_link(Args)->
supervisor:start_link({local,?MODULE},?MODULE,Args).
test()->
{ok,Pid}=supervisor:start_link({local,?MODULE},?MODULE,[]),
unlink(Pid).
init([])->
gen_event:swap_handler(alarm_handler,{alarm_handler,swap},{job_center_alarm,[]}),
{ok,{{one_for_one,?MAXRESTARTS,?TIME},
[{job_center,
{job_center,start_link,[]},
permanent,
10000,
worker,
[job_center]
}
]}}.
4.job_center.app [application资源文件]
{application,job_center_app,
[{description,"A Job Deliver Center 1.0"},
{vsn,"1.0"},
{modules,[job_center_app,job_center,job_center_supervisor,job_center_alarm]},
{registered,[job_center]},
{applications,[kernel,stdlib]},
{mod,{job_center_app,[]}},
{start_phases,[]}
]}.
5.job_center.erl [gen_server构建的服务器]
-module(job_center).
-behaviour(gen_server).
-export([code_change/3,terminate/2,test/0,start_link/0,job_getStatistic/1,stop/0,init/1,add_job/1,work_wanted/0,job_done/2,handle_call/3,handle_cast/2,handle_info/2,job_statistic/0]).
-import(gen_server,[start_link/4,call/2]).
-spec add_job(fun())->integer().
-define(debug_flag,true).
-ifdef(debug_flag).
-define(DEBUG(X),io:format("DEBUG ~p:~p ~p~n",[?MODULE,?LINE,X])).
-else.
-define(DEBUG(X),void).
-endif.
test()->
start_link(),
job_center:add_job(fun()->good_job end).
start_link()->
io:format("start_link_now!~n"),
start_link({local,?MODULE},?MODULE,[],[]).
stop()->
call(?MODULE,stop).
init([])->
io:format("job_center Start!~n"),
%process_flag(trap_exit,true),
State=ets:new(?MODULE,[]),
ets:insert(State,{job_index,0}),
{ok,State}.
% user api
add_job(Fun)->
call(?MODULE,{add_job,Fun}).
work_wanted()->
call(?MODULE,{work_wanted}).
job_done(JobNumber,Status)->
io:format("Request change Job:~p Status:~p~n",[JobNumber,Status]),
call(?MODULE,{job_done,JobNumber,Status}).
job_statistic()->
call(?MODULE,{job_statistic}).
job_getStatistic(Index)->
call(?MODULE,{job_getStatistic,Index}).
% callback Function
handle_call({job_getStatistic,Index},_From,State)->
{reply,ets:lookup_element(State,Index,3),State};
handle_call({job_statistic},_From,State)->
%未完成的任务数
Match_not_done=ets:match(State,{'$1','$2',not_done}),
io:format("未完成的数量:~p~n",[length(Match_not_done)]),
Match_doing=ets:match(State,{'$1','$2',doing}),
io:format("正在进行的数量:~p~n",[length(Match_doing)]),
Match_done=ets:match(State,{'$1','$2',done}),
io:format("已完成的数量:~p~n",[length(Match_done)]),
{reply,show_all_finish,State};
handle_call({add_job,Fun},_From,State)->
[{job_index,Index}]=ets:lookup(State,job_index),
ets:insert(State,[{job_index,Index+1},{Index,Fun,not_done}]),
Reply=ok,
{reply,Reply,State};
handle_call({work_wanted},{Pid,_Ref},State)->
Match_Ret=ets:match(State,{'$1','$2',not_done},1),
case Match_Ret of
'$end_of_table'->%没job了
Fun=void,
Index=-1,
{reply,{no_job_now,Index,Fun},State};
{[[Index,Fun]],_}->%判断表中还有未完成的job
ets:update_element(State,Index,{3,doing}),%更新状态为doing正在进行
%-------------------检测崩溃
spawn_link(fun()->
Ref=monitor(process,Pid),
receive
{'DOWN',Ref,process,Pid,Why}->
io:format("worker:~p leave for ~p ~n",[Pid,Why]),
Bool=Why=:=normal,
if
Bool=:=false->
job_center:job_done(Index,not_done);
Bool=:=true->
void
end
end
end),%监控是否崩溃防止崩溃时数据停留
%-------------------检测超时
spawn(fun()->
timer:sleep(4000),
case ets:lookup_element(State,Index,3) of
doing->Pid ! {hurry_up};
_->ok
end,
timer:sleep(2000),
exit(Pid,you_are_fired)
end),%检测超时，超过6秒就炒鱿鱼
{reply,{get_job_succ,Index,Fun,5000},State}
end;
handle_call({job_done,JobNumber,Status},_From,State)->
case ets:member(State,JobNumber) of%首先判断这个键值是否存在，存在才可以去lookup否则报错
true->
Status_change_before=ets:lookup_element(State,JobNumber,3),
%io:format("Match:~p~n",[Status_change_before]),
case Status_change_before of
done->
Reply=aleady_done;
doing->
Reply=good_job,
io:format("comfirm to change the status:~p of Index~p~n",[Status,JobNumber]),
ets:update_element(State,JobNumber,{3,Status});
not_done->
Reply=did_not_been_got
end,
{reply,Reply,State};
false->
{reply,job_not_found,State}
end;
handle_call(stop,_From,State)->
io:format("good bye!~n"),
{stop,normal,stopped,State}.
handle_cast(_Msg,State)->
{noreply,State}.
handle_info(_Info,State)->
{noreply,State}.
terminate(_Reason,_State)->ok.
code_change(_OldVsn,State,_Extra)->{ok,State}.
