我在尝试设置 Quartz 时遇到 DI 注册问题,该作业是一个简单的测试作业,用于确认 DI 正在工作(仅将文本输出到控制台)。
抛出错误的代码位于最后一个类JobFactory
中。
Program.cs
static async Task Main(string[] args)
{
var isService = !(Debugger.IsAttached || ((IList)args).Contains("--console"));
var path = Path.GetDirectoryName(new Uri(Assembly.GetExecutingAssembly().CodeBase).LocalPath);
var webHost = new HostBuilder()
.ConfigureAppConfiguration((cxt, config) =>
{
config.SetBasePath(path);
config.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);
config.AddJsonFile($"appsettings.{environmentName}.json", optional: true, reloadOnChange: true);
config.AddEnvironmentVariables();
if (args != null)
{
config.AddCommandLine(args);
}
Log.Logger = new LoggerConfiguration()
.ReadFrom.Configuration(config.Build())
.Enrich.FromLogContext()
.CreateLogger();
})
.ConfigureServices((cxt, services) =>
{
var configuration = cxt.Configuration;
var bw = new BackgroundWorker(services.BuildServiceProvider());
services.AddSingleton<IHostedService>(bw);
services.AddLogging(loggingBuilder => loggingBuilder.AddSerilog(dispose: true));
//services.AddSingleton<ISchedulerFactory, SchedulerFactory>();
//services.AddSingleton<ScopedJobFactory>();
services.AddScoped(_ => new SomeJob(configuration));
//services.AddTransient<IJob>(_ => new SomeJob(configuration));
var token = tokenSource.Token;
if (isService)
{
await webHost.RunAsServiceAsync(token);
}
else
{
await webHost.RunConsoleAsync(token);
}
}
设置 Quartz 作业工厂:
private static async Task<IScheduler> InitiateQuartzScheduler(IServiceProvider serviceProvider)
{
try
{
var factory = new StdSchedulerFactory();
var scheduler = await factory.GetScheduler();
scheduler.JobFactory = new JobFactory(serviceProvider);
await scheduler.Start();
return scheduler;
}
catch (SchedulerException se)
{
Log.Logger.Fatal(se, "Error at starting the Quartz Scheduler");
}
return null;
}
后台 worker :
private class BackgroundWorker : IHostedService
{
private IScheduler quartzScheduler;
private readonly IServiceProvider serviceProvider;
public BackgroundWorker(IServiceProvider serviceProvider)
{
this.serviceProvider = serviceProvider;
}
public async Task StartAsync(CancellationToken cancellationToken)
{
//Log.Logger = SetupSerilog();
Log.Logger.Information("Starting Quartz BackgroundWorker.");
quartzScheduler = await InitiateQuartzScheduler(serviceProvider);
}
public async Task StopAsync(CancellationToken cancellationToken)
{
Log.Logger.Information("Quartz Background Worker is stopping.");
}
}
作业工厂(发生错误的位置):
internal class JobFactory : IJobFactory
{
protected readonly IServiceProvider serviceProvider;
protected readonly ConcurrentDictionary<IJob, IServiceScope> _scopes = new ConcurrentDictionary<IJob, IServiceScope>();
public JobFactory(IServiceProvider serviceProvider)
{
this.serviceProvider = serviceProvider;
}
public IJob NewJob(TriggerFiredBundle bundle, IScheduler scheduler)
{
var scope = serviceProvider.CreateScope();
IJob job;
try
{
//
// **ERROR HERE**
//
job = scope.ServiceProvider.GetRequiredService(bundle.JobDetail.JobType) as IJob;
}
catch
{
// Failed to create the job -> ensure scope gets disposed
scope.Dispose();
throw;
}
// Add scope to dictionary so we can dispose it once the job finishes
if (!_scopes.TryAdd(job, scope))
{
// Failed to track DI scope -> ensure scope gets disposed
scope.Dispose();
throw new Exception("Failed to track DI scope");
}
return job;
}
public void ReturnJob(IJob job)
{
if (_scopes.TryRemove(job, out var scope))
{
// The Dispose() method ends the scope lifetime.
// Once Dispose is called, any scoped services that have been resolved from ServiceProvider will be disposed.
scope.Dispose();
}
}
}
运行时错误:
System.InvalidOperationException: 'No service for type 'xxx.yyy.SomeJob' has been registered.'
最佳答案
在添加所有必需的依赖项之前,将为后台工作人员提供一个提供程序。
//...
var configuration = cxt.Configuration;
var bw = new BackgroundWorker(services.BuildServiceProvider()); //<---This service provider
services.AddSingleton<IHostedService>(bw);
services.AddLogging(loggingBuilder => loggingBuilder.AddSerilog(dispose: true));
services.AddScoped(_ => new SomeJob(configuration)); //<--knows nothing about this service
//...or any other service added after services.BuildServiceProvider()
//...
构建服务集合后,集合中的任何更改(添加/删除)都不会影响已构建的提供程序。
在注册工作人员时考虑改变方法并使用延迟委托(delegate)工厂
//...
services.AddSingleton<IHostedService>(serviceProvider => new BackgroundWorker(serviceProvider));
//...
关于c# - Quartz.net Core 中的依赖注入(inject)未找到注册服务,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56634078/