用于依赖注入(inject)的 Azure 触发的 Webjobs 范围

我已经阅读并询问了一些关于如何使用 WebJob 使用 DI 的问题，尤其是 Triggered Webjobs。

SimpleInjector - Azure WebJob with TimerTrigger - Register IDisposable

Dependency injection using Azure WebJobs SDK?

我仍然试图弄清楚如何在触发的 webjobs 中优雅地集成 DI，@Steven 问了我一个很好的问题:



我知道我可以在我的触发函数中启动一个范围，但我想知道 sdk 中是否有任何可扩展性点允许我们进行范围界定？

谢谢。

最佳答案

我已向 Azure Webjob 团队提出了 Add IDependencyScope to handle scoping 请求。

我创建了一个小型库来围绕 Azure Webjobs 和 SimpleInjector 收集类:

Nuget download

GitHub project

对于 QueueTrigger 和 ServiceBustrigger，我遇到了这些解决方案:

ServiceBusTrigger(来自这个答案:https://stackoverflow.com/a/33759649/4167200):

public sealed class ScopedMessagingProvider : MessagingProvider
{
    private readonly ServiceBusConfiguration _config;
    private readonly Container _container;

    public ScopedMessagingProvider(ServiceBusConfiguration config, Container container)
        : base(config)
    {
        _config = config;
        _container = container;
    }

    public override MessageProcessor CreateMessageProcessor(string entityPath)
    {
        return new ScopedMessageProcessor(_config.MessageOptions, _container);
    }

    private class ScopedMessageProcessor : MessageProcessor
    {
        private readonly Container _container;

        public ScopedMessageProcessor(OnMessageOptions messageOptions, Container container)
            : base(messageOptions)
        {
            _container = container;
        }

        public override Task<bool> BeginProcessingMessageAsync(BrokeredMessage message, CancellationToken cancellationToken)
        {
            _container.BeginExecutionContextScope();
            return base.BeginProcessingMessageAsync(message, cancellationToken);
        }

        public override Task CompleteProcessingMessageAsync(BrokeredMessage message, FunctionResult result, CancellationToken cancellationToken)
        {
            _container.GetCurrentExecutionContextScope()?.Dispose();
            return base.CompleteProcessingMessageAsync(message, result, cancellationToken);
        }
    }
}

您可以在 JobHostConfiguration 中使用您的自定义 MessagingProvider，例如

var serviceBusConfig = new ServiceBusConfiguration
{
    ConnectionString = config.ServiceBusConnectionString
};
serviceBusConfig.MessagingProvider = new ScopedMessagingProvider(serviceBusConfig, container);
jobHostConfig.UseServiceBus(serviceBusConfig);

队列触发器:

public sealed class ScopedQueueProcessorFactory : IQueueProcessorFactory
{
    private readonly Container _container;

    public ScopedQueueProcessorFactory(Container container)
    {
        _container = container;
    }

    public QueueProcessor Create(QueueProcessorFactoryContext context)
    {
        return new ScopedQueueProcessor(context, _container);
    }

    private class ScopedQueueProcessor : QueueProcessor
    {
        private readonly Container _container;

        public ScopedQueueProcessor(QueueProcessorFactoryContext context, Container container)
            : base(context)
        {
            _container = container;
        }

        public override Task<bool> BeginProcessingMessageAsync(CloudQueueMessage message, CancellationToken cancellationToken)
        {
            _container.BeginExecutionContextScope();
            return base.BeginProcessingMessageAsync(message, cancellationToken);
        }

        public override Task CompleteProcessingMessageAsync(CloudQueueMessage message, FunctionResult result,
            CancellationToken cancellationToken)
        {
            _container.GetCurrentExecutionContextScope()?.Dispose();
            return base.CompleteProcessingMessageAsync(message, result, cancellationToken);
        }
    }
}

您可以在 JobHostConfiguration 中使用自定义 IQueueProcessorFactory ，如下所示:

 var config = new JobHostConfiguration();
 config.Queues.QueueProcessorFactory = new ScopedQueueProcessorFactory(container);

关于用于依赖注入(inject)的 Azure 触发的 Webjobs 范围，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/35186456/