做爲一枚後端程序狗,項目實踐常遇到定時任務的工做,最容易想到的的思路就是利用Windows計劃任務/wndows service程序/Crontab程序等主機方法在主機上部署定時任務程序/腳本。web
可是不少時候,若使用的是共享主機或者受控主機,這些主機不容許你私自安裝exe程序、Windows服務程序。redis
碼甲會想到在web程序中作定時任務, 目前有兩個方向:sql
①.AspNetCore自帶的HostService, 這是一個輕量級的後臺服務, 須要搭配timer完成定時任務數據庫
②.老牌Quartz.Net組件,支持複雜靈活的Scheduling、支持ADO/RAM Job任務存儲、支持集羣、支持監聽、支持插件。後端
此處咱們的項目使用稍複雜的Quartz.net實現web定時任務。架構
最近須要作一個計數程序:採用redis計數,設定每小時將當日累積數據持久化到關係型數據庫sqlite。app
①.定義定時任務內容: Jobasync
②.設置觸發條件: Triggeride
③.將Quartz.Net集成進AspNet Core函數
IScheduler類包裝了上述背景須要完成的第①②點工做 ,SimpleJobFactory定義了生成指定的Job任務的過程,這個行爲是利用反射機制調用無參構造函數構造出的Job實例。下面是源碼:
//----------------選自Quartz.Simpl.SimpleJobFactory類------------- using System; using Quartz.Logging; using Quartz.Spi; using Quartz.Util; namespace Quartz.Simpl { /// <summary> /// The default JobFactory used by Quartz - simply calls /// <see cref="ObjectUtils.InstantiateType{T}" /> on the job class. /// </summary> /// <seealso cref="IJobFactory" /> /// <seealso cref="PropertySettingJobFactory" /> /// <author>James House</author> /// <author>Marko Lahma (.NET)</author> public class SimpleJobFactory : IJobFactory { private static readonly ILog log = LogProvider.GetLogger(typeof (SimpleJobFactory)); /// <summary> /// Called by the scheduler at the time of the trigger firing, in order to /// produce a <see cref="IJob" /> instance on which to call Execute. /// </summary> /// <remarks> /// It should be extremely rare for this method to throw an exception - /// basically only the case where there is no way at all to instantiate /// and prepare the Job for execution. When the exception is thrown, the /// Scheduler will move all triggers associated with the Job into the /// <see cref="TriggerState.Error" /> state, which will require human /// intervention (e.g. an application restart after fixing whatever /// configuration problem led to the issue with instantiating the Job). /// </remarks> /// <param name="bundle">The TriggerFiredBundle from which the <see cref="IJobDetail" /> /// and other info relating to the trigger firing can be obtained.</param> /// <param name="scheduler"></param> /// <returns>the newly instantiated Job</returns> /// <throws> SchedulerException if there is a problem instantiating the Job. </throws> public virtual IJob NewJob(TriggerFiredBundle bundle, IScheduler scheduler) { IJobDetail jobDetail = bundle.JobDetail; Type jobType = jobDetail.JobType; try { if (log.IsDebugEnabled()) { log.Debug($"Producing instance of Job '{jobDetail.Key}', class={jobType.FullName}"); } return ObjectUtils.InstantiateType<IJob>(jobType); } catch (Exception e) { SchedulerException se = new SchedulerException($"Problem instantiating class '{jobDetail.JobType.FullName}'", e); throw se; } } /// <summary> /// Allows the job factory to destroy/cleanup the job if needed. /// No-op when using SimpleJobFactory. /// </summary> public virtual void ReturnJob(IJob job) { var disposable = job as IDisposable; disposable?.Dispose(); } } } //------------------節選自Quartz.Util.ObjectUtils類------------------------- public static T InstantiateType<T>(Type type) { if (type == null) { throw new ArgumentNullException(nameof(type), "Cannot instantiate null"); } ConstructorInfo ci = type.GetConstructor(Type.EmptyTypes); if (ci == null) { throw new ArgumentException("Cannot instantiate type which has no empty constructor", type.Name); } return (T) ci.Invoke(new object[0]); }
不少時候,定義的Job任務依賴了其餘組件(Job實例化時多參),此時默認的SimpleJobFactory不能知足實例化要求, 須要考慮將Job任務做爲依賴注入組件,加入依賴注入容器。
關鍵思路:
① IScheduler 開放了JobFactory 屬性,便於你控制Job任務的實例化方式;
② AspNet Core的服務架構是以依賴注入爲基礎的,利用ASPNET Core已有的依賴注入容器IServiceProvider管理Job任務的建立過程。
① 定義Job內容:
// -------每小時將redis數據持久化到sqlite, 每日凌晨跳針,持久化昨天全天數據--------------------- public class UsageCounterSyncJob : IJob { private readonly EqidDbContext _context; private readonly IDatabase _redisDB1; private readonly ILogger _logger; public UsageCounterSyncJob(EqidDbContext context, RedisDatabase redisCache, ILoggerFactory loggerFactory) { _context = context; _redisDB1 = redisCache[1]; _logger = loggerFactory.CreateLogger<UsageCounterSyncJob>(); } public async Task Execute(IJobExecutionContext context) { // 觸發時間在凌晨,則同步昨天的計數 var _day = DateTime.Now.ToString("yyyyMMdd"); if (context.FireTimeUtc.LocalDateTime.Hour == 0) _day = DateTime.Now.AddDays(-1).ToString("yyyyMMdd"); await SyncRedisCounter(_day); _logger.LogInformation("[UsageCounterSyncJob] Schedule job executed."); } ...... }
②註冊Job和Trigger:
namespace EqidManager { using IOCContainer = IServiceProvider; // Quartz.Net啓動後註冊job和trigger public class QuartzStartup { public IScheduler _scheduler { get; set; } private readonly ILogger _logger; private readonly IJobFactory iocJobfactory; public QuartzStartup(IOCContainer IocContainer, ILoggerFactory loggerFactory) { _logger = loggerFactory.CreateLogger<QuartzStartup>(); iocJobfactory = new IOCJobFactory(IocContainer); var schedulerFactory = new StdSchedulerFactory(); _scheduler = schedulerFactory.GetScheduler().Result; _scheduler.JobFactory = iocJobfactory; } public void Start() { _logger.LogInformation("Schedule job load as application start."); _scheduler.Start().Wait(); var UsageCounterSyncJob = JobBuilder.Create<UsageCounterSyncJob>() .WithIdentity("UsageCounterSyncJob") .Build(); var UsageCounterSyncJobTrigger = TriggerBuilder.Create() .WithIdentity("UsageCounterSyncCron") .StartNow() // 每隔一小時同步一次 .WithCronSchedule("0 0 * * * ?") // Seconds,Minutes,Hours,Day-of-Month,Month,Day-of-Week,Year(optional field) .Build(); _scheduler.ScheduleJob(UsageCounterSyncJob, UsageCounterSyncJobTrigger).Wait(); _scheduler.TriggerJob(new JobKey("UsageCounterSyncJob")); } public void Stop() { if (_scheduler == null) { return; } if (_scheduler.Shutdown(waitForJobsToComplete: true).Wait(30000)) _scheduler = null; else { } _logger.LogCritical("Schedule job upload as application stopped"); } } /// <summary> /// IOCJobFactory :實如今Timer觸發的時候注入生成對應的Job組件 /// </summary> public class IOCJobFactory : IJobFactory { protected readonly IOCContainer Container; public IOCJobFactory(IOCContainer container) { Container = container; } //Called by the scheduler at the time of the trigger firing, in order to produce // a Quartz.IJob instance on which to call Execute. public IJob NewJob(TriggerFiredBundle bundle, IScheduler scheduler) { return Container.GetService(bundle.JobDetail.JobType) as IJob; } // Allows the job factory to destroy/cleanup the job if needed. public void ReturnJob(IJob job) { } } }
③結合AspNet Core 注入組件;綁定Quartz.Net
//-------------------------------截取自Startup文件------------------------ ...... services.AddTransient<UsageCounterSyncJob>(); // 這裏使用瞬時依賴注入 services.AddSingleton<QuartzStartup>(); ...... // 綁定Quartz.Net public void Configure(IApplicationBuilder app, Microsoft.AspNetCore.Hosting.IApplicationLifetime lifetime, ILoggerFactory loggerFactory) { var quartz = app.ApplicationServices.GetRequiredService<QuartzStartup>(); lifetime.ApplicationStarted.Register(quartz.Start); lifetime.ApplicationStopped.Register(quartz.Stop); }
附:IIS 網站低頻訪問致使工做進程進入閒置狀態的 解決辦法
IIS上低頻web訪問會形成工做進程關閉,此時應用程序池回收,Timer等線程資源會被銷燬;當工做進程從新運做,Timer可能會從新生成起效, 但咱們的設定的定時Job可能沒有按需正確執行。
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