我有以下申请:
1) Mvc app :Hangfire客户端,我将在那里将作业和主机排入队列 仪表板。这个应用程序将包含我的类库的参考。
2)控制台应用:Hangfire服务器将存在于此控制台应用程序中。
3)类库:hangfire服务器(控制台应用)和hangfire客户端(asp.net mvc)之间的共享库,我的长时间运行的代码将驻留在那里.Hangfire服务器 将执行该库的代码。
之后的类库中有如下结构以下代码:Reference:
接口
public interface IOperation
{
Output Process(Input input);
bool AppliesTo(Type type);
}
public interface IOperationStrategy
{
Output Process(Type type,Input input);
}
运营:
public class Add : IOperation
{
public bool AppliesTo(Type type)
{
return typeof(Add).Equals(type);
}
public Output Process(Input input)
{
// Implementation
return new Output();
}
}
public class Multiply : IOperation
{
public bool AppliesTo(Type type)
{
return typeof(Multiply).Equals(type);
}
public Output Process(Input input)
{
// Implementation
return new Output();
}
}
策略:
public class OperationStrategy : IOperationStrategy
{
private readonly IOperation[] operations;
public OperationStrategy(params IOperation[] operations)
{
if (operations == null)
throw new ArgumentNullException(nameof(operations));
this.operations = operations;
}
public Output Process(Type type, Input input)
{
var op = operations.FirstOrDefault(o => o.AppliesTo(type));
if (op == null)
throw new InvalidOperationException($"{operation} not registered.");
return op.Process(input);
}
}
用法:
// Do this with your DI container in your composition
// root, and the instance would be created by injecting
// it somewhere.
var strategy = new OperationStrategy(
new Add(), // Inject any dependencies for operation here
new Multiply()); // Inject any dependencies for operation here
// And then once it is injected, you would simply do this.
var input = new Input { Value1 = 2, Value2 = 3 };
BackgroundJob.Enqueue(() => strategy.Process(typeof(Add), input));
但是hangfire服务器无法选择工作,当我检查state table
时,我会看到如下错误:
“FailedAt”:“2018-03-21T13:14:46.0172303Z”,“ExceptionType”: “System.MissingMethodException”,“ExceptionMessage”:“没有无参数 为此对象定义的构造函数。“,”ExceptionDetails“: “System.MissingMethodException:未定义无参数构造函数 对于这个对象。\ r \ n at System.RuntimeTypeHandle.CreateInstance(RuntimeType类型,布尔值 publicOnly,Boolean noCheck,Boolean& canBeCached, RuntimeMethodHandleInternal&安培; ctor,布尔& bNeedSecurityCheck)\ r \ n at System.RuntimeType.CreateInstanceSlow(Boolean publicOnly,Boolean skipCheckThis,Boolean fillCache,StackCrawlMark& stackMark)\ r \ n at System.Activator.CreateInstance(Type type,Boolean nonPublic)\ r \ n at System.Activator.CreateInstance(Type type)\ r \ n at Hangfire.JobActivator.SimpleJobActivatorScope.Resolve(Type type)\ r \ n 在Hangfire.Server.CoreBackgroundJobPerformer.Perform(PerformContext 上下文)\ r \ n at Hangfire.Server.BackgroundJobPerformer<> c__DisplayClass8_0.b__0(个)\ r \ n 在 Hangfire.Server.BackgroundJobPerformer.InvokePerformFilter(IServerFilter filter,PerformingContext preContext,Func 1 continuation)\ r \ n at Hangfire.Server.BackgroundJobPerformer.PerformJobWithFilters(PerformContext 上下文,IEnumerable`1过滤器)\ r \ n at Hangfire.Server.BackgroundJobPerformer.Perform(PerformContext 上下文)\ r \ n at Hangfire.Server.Worker.PerformJob(BackgroundProcessContext context, IStorageConnection连接,String jobId)“
我没有得到应该为这个结构设置的hangfire,因为我没有涉及任何IOC容器。
有人可以帮帮我吗?
演示项目:https://www.dropbox.com/s/bfjr58y6azgmm3w/HFDemo.zip?dl=0
答案 0 :(得分:1)
答案就在那里
No parameterless constructor defined for this object.
您的OperationStrategy
没有无参数构造函数,因此当Hangfire尝试创建此对象时,它无法通过反射来实现。
Hangfire无权访问您在计划作业时使用的实例,它会尝试重新创建它。它无法做到。
您可以添加无参数构造函数,并将Operations
设为公共集合。
这将使您能够像现在一样使用ctor,但也允许对象被序列化,由Hangfire存储,然后反序列化并在尝试运行时创建。
public class OperationStrategy : IOperationStrategy
{
// paramaterless ctor
public OperationStrategy()
{
Operations = new List<Operation>();
}
public OperationStrategy(params IOperation[] operations)
{
if (operations == null)
throw new ArgumentNullException(nameof(operations));
Operations = operations;
}
public Output Process(Type type, Input input)
{
var op = Operations.FirstOrDefault(o => o.AppliesTo(type));
if (op == null)
throw new InvalidOperationException($"{operation} not registered.");
return op.Process(input);
}
//property - this can be deserialized by Hangfire
public List<IOperation> Operations {get; set;}
}