In ServiceStack 3 I had a custom handler decorating the result DTO in case of exceptions:
ServiceExceptionHandler = (request, exception) =>
{
var ret = DtoUtils.HandleException(this, request, exception);
var error = ret as HttpError;
if ( error == null )
return ret;
// ...
error.Response = new MyErrorResponse
{
ResponseStatus = responseStatus,
// ...
};
return ret;
};
After migrating to ServiceStack 4 I tried different hooks:
ServiceExceptionHandlers.Add
OnExceptionTypeFilter
Own ServiceRunner with overridden HandleException
Neither of them is been called when exceptions occur. What am I missing?
I'm using the new Task based services, if this is relevant.
Edit: A simple test service included in my solution triggers the hooks:
[Route("/test")]
public class TestRequest : IReturn<int>
{
}
public class TestService : Service
{
public Task<int> Get(TestRequest request)
{
throw new Exception("Ha!");
}
}
Edit2: Seems to be a bug in the handling of asynchronous services. If I move the exception from the synchronous to the asynchronous part of the handler, none of the hooks are called:
public class TestService : Service
{
public async Task<int> Get(TestRequest request)
{
await Task.Yield();
throw new Exception("Ha!");
}
}
Related
I try to create OWIN(IIS Hosted) middleware that will ensure that all log4net events will have a particular property (CorrelationId) assigned per-request.
I tried to:
Use following middleware and use IOwinContext.
It works only when appender batching size is to 1. Otherwise, the whole batch of events is assigned the same CorrelationId.
public class CorrelationIdMiddleware : OwinMiddleware
{
public CorrelationIdMiddleware(OwinMiddleware next): base(next){}
public override async Task Invoke(IOwinContext context)
{
correlationId = Guid.NewGuid().ToString();
context.Set("CorrelationId", correlationId);
await Next.Invoke(context);
}
}
Middleware was paired with log4net active property:
public class CorrelationIdActiveLog4NetValue
{
public override string ToString()
{
var context = HttpContext.Current.GetOwinContext();
if (context != null)
{
var value = context.Get<string>("CorrelationId");
if (!string.IsNullOrEmpty(value))
{
return value;
}
}
return "N/A";
}
}
Use LogicalCallContext.
var stack = log4net.LogicalThreadContext.Stacks["CorrelationId"]
using (stack.Push(correlationId))
{
log4net.LogManager.GetLogger(typeof(CorrelationIdMiddleware))
.Info("TEST MESSAGE");
await Next.Invoke(context);
}
It worked for the message I produced in the middleware itself, but not when I logged from controllers.
For comparison, in Serilog such middleware code works universally in every case(ASP.NET core):
using (LogContext.PushProperty("BayCorrelationId", context.TraceIdentifier))
{
await next(context);
}
In the Azure app service mobile backend service, REST API requests are handled by TableController implementation. These methods can be invoked by using corresponding methods available in client SDKs. So, i can query for a particular entity and update its status from the client side.
But how to invoke them in the server side or within the same controller? For example, if I want to query for a particular todoItem and update its status from some custom method here like
Use LookUp(id) to get the item
Update the status
Use UpdateAsync(id, item)
Here I don't know how to create a Delta object of TodoItem to call UpdateAsync(id, patch) method.
public class TodoItemController : TableController<TodoItem>
{
protected override void Initialize(HttpControllerContext controllerContext)
{
base.Initialize(controllerContext);
initrackerserviceContext context = new initrackerserviceContext();
DomainManager = new EntityDomainManager<TodoItem>(context, Request);
}
// GET tables/TodoItem
public IQueryable<TodoItem> GetAllTodoItems()
{
return Query();
}
// GET tables/TodoItem/48D68C86-6EA6-4C25-AA33-223FC9A27959
public SingleResult<TodoItem> GetTodoItem(string id)
{
return Lookup(id);
}
// PATCH tables/TodoItem/48D68C86-6EA6-4C25-AA33-223FC9A27959
public Task<TodoItem> PatchTodoItem(string id, Delta<TodoItem> patch)
{
return UpdateAsync(id, patch);
}
// POST tables/TodoItem
public async Task<IHttpActionResult> PostTodoItem(TodoItem item)
{
TodoItem current = await InsertAsync(item);
return CreatedAtRoute("Tables", new { id = current.Id }, current);
}
// DELETE tables/TodoItem/48D68C86-6EA6-4C25-AA33-223FC9A27959
public Task DeleteTodoItem(string id)
{
return DeleteAsync(id);
}
}
Just use the standard Entity Framework mechanisms. For instance, to find and update a record with a status, you can just use the context:
var item = await context.TodoItems.Where(i => i.Id.Equals(myId)).FirstOrDefaultAsync<TodoItem>();
if (item != null) {
item.Complete = true;
context.Entry(item).State = EntityState.Modified;
await context.SaveChangesAsync();
}
My EF coding is not the greatest ad-hoc, but you should get the idea. Just do the Entity Framework thing.
It's better to use TableController.ReplaceAsync() method that is already implemented for us here in the source code of EntityDomainManager.
var item = Lookup(item.Id).Queryable.FirstOrDefault();
if (item != null)
{
item.Complete = true;
item = await ReplaceAsync(item.Id, item);
}
The ReplaceAsync() method correctly handles the exceptions, so I would not recommend working directly with the EF context.
How do I configure ServiceStack to serve specific error pages (404, 500, etc.) depending on the type of error being returned?
Currently, I'm using the RawHttpHandler below code to ensure that a request for a HTML file is authenticated. However, if the user specifies a non-existent file or endpoint, how can I have it return my 404.html page.
this.RawHttpHandlers.Add(httpReq =>
{
var session = httpReq.GetSession();
if(!session.IsAuthenticated) {
var isHtmlFileRequest = httpReq.PathInfo.EndsWith(".html");
if(isHtmlFileRequest && !files.Any(s => httpReq.PathInfo.ToLower().Contains(s))) {
return new RedirectHttpHandler {
AbsoluteUrl = "/Login.html"
};
}
}
return null;
});
The Error Handling wiki shows different ways to Customize Handling of Exceptions in ServiceStack, e.g you can redirect 404 errors to /404.cshtml with:
public override void Configure(Container container)
{
this.CustomHttpHandlers[HttpStatusCode.NotFound] =
new RazorHandler("/404");
}
CustomHttpHandlers can be any IServiceStackHandler which is just a HttpHandler that supports both ASP.NET and HttpListener requests. The easiest way to create one is to just inherit from IServiceStackHandler. Here's an example of a Custom Static File Handler similar to StaticFileHandler except it only writes the specified filePath instead of using the HTTP Request path:
public class CustomStaticFileHandler : HttpAsyncTaskHandler
{
string filePath;
public CustomStaticFileHandler(string filePath)
{
this.filePath = filePath;
}
public override void ProcessRequest(HttpContextBase context)
{
var httpReq = context.ToRequest(GetType().GetOperationName());
ProcessRequest(httpReq, httpReq.Response, httpReq.OperationName);
}
public override void ProcessRequest(IRequest request, IResponse response,
string operationName)
{
response.EndHttpHandlerRequest(skipClose: true, afterHeaders: r =>
{
var file = HostContext.VirtualPathProvider.GetFile(filePath);
if (file == null)
throw new HttpException(404, "Not Found");
r.SetContentLength(file.Length);
var outputStream = r.OutputStream;
using (var fs = file.OpenRead())
{
fs.CopyTo(outputStream, BufferSize);
outputStream.Flush();
}
}
}
}
This can then be registered as normal, i.e:
public override void Configure(Container container)
{
this.CustomHttpHandlers[HttpStatusCode.NotFound] =
new CustomStaticFileHandler("/404.html");
}
I'm trying to use the ServiceExceptionHandler on my Serivce which extends RestServiceBase<TViewModel>
I can use the AppHost.ServiceExceptionHandler, that's working fine. I need the user info from the HttpRequest, thats not available at AppHost level.
So I'm trying to use the ServiceExceptionHandler on Service level. Though I set the delegate on service ctor, it's null when exception thrown on OnGet method
public class StudentService : RestServiceBase<Student>
{
public StudentService()
{
ServiceExceptionHandler = (request, exception) =>
{
logger.Error(string.Format("{0} - {1} \n Request : {2}\n", HttpRequest.UserName(), exception.Message, request.Dump()), exception);
var errors = new ValidationErrorField[] { new ValidationErrorField("System Error", "TODO", "System Error") };
return DtoUtils.CreateErrorResponse("System Error", "System Error", errors);
};
}
}
I'm not sure of what is the issue with this code. Any help will be appreciated.
Register Global AppHost.ServiceExceptionHandler
In your AppHost.Configure() you can register a global Exception handler with:
this.ServiceExceptionHandler = (request, ex) => {
... //handle exception and generate your own ErrorResponse
};
For finer-grained Exception handlers you can override the following custom service event hooks:
Handling Exceptions with the New API
If you're using the New API you can override the Exception by providing a custom runner, e.g:
public class AppHost {
...
public virtual IServiceRunner<TRequest> CreateServiceRunner<TRequest>(
ActionContext actionContext)
{
//Cached per Service Action
return new ServiceRunner<TRequest>(this, actionContext);
}
}
public class MyServiceRunner<T> : ServiceRunner<T> {
public override object HandleException(
IRequestContext requestContext, TRequest request, Exception ex) {
// Called whenever an exception is thrown in your Services Action
}
}
Handling Exceptions with the Old API
RestServiceBase<T> is uses the old API in which you can handle errors by overriding the HandleException method, e.g:
public class StudentService : RestServiceBase<Student>
{
...
protected override object HandleException(T request, Exception ex)
{
LogException(ex);
return base.HandleException(request, ex);
}
}
In my MVC 2 project, I originally used Ninject 2 and wrote this version of the NinjectControllerFactory:
public class NinjectControllerFactory : DefaultControllerFactory
{
private IKernel kernel = new StandardKernel(new HandiGamerServices());
protected override IController GetControllerInstance(System.Web.Routing.RequestContext requestContext, Type controllerType)
{
try
{
if (controllerType == null)
{
return base.GetControllerInstance(requestContext, controllerType);
// return null;
}
}
catch (HttpException ex)
{
if (ex.GetHttpCode() == 404)
{
IController errorController = kernel.Get<ErrorController>();
((ErrorController)errorController).InvokeHttp404(requestContext.HttpContext);
return errorController;
}
else
{
throw ex;
}
}
return (IController)kernel.Get(controllerType);
}
Of most importance is the retrieval of my ErrorController, which allows me to gracefully handle a multitude of HTTP errors.
The problem is that I upgraded to the MVC 2 extension via Nuget, so a NinjectControllerFactory is already provided. Would it be possible to use my own override of GetControllerInstance? If so, how?
I do exactly this, and for precisely the same reason. In Global.asax.cs, I add this to my OnApplicationStarted override (declared virtual in NinjectHttpApplication):
ControllerBuilder.Current.SetControllerFactory(
new MyControllerFactory(ControllerBuilder.Current.GetControllerFactory()));
This means you're creating your own controller factory, but providing it with the default implementation to do the heavy lifting.
Then define your controller factory like so:
public class MyControllerFactory : IControllerFactory
{
private IControllerFactory defaultFactory;
public MyControllerFactory(IControllerFactory defaultFactory)
{
this.defaultFactory = defaultFactory;
}
public IController CreateController(RequestContext requestContext, string controllerName)
{
try
{
var controller = defaultFactory.CreateController(requestContext, controllerName);
return controller;
}
catch (HttpException e)
{
// Pasted in your exception handling code here:
if (ex.GetHttpCode() == 404)
{
IController errorController = kernel.Get<ErrorController>();
((ErrorController)errorController).InvokeHttp404(requestContext.HttpContext);
return errorController;
}
else
{
throw ex;
}
}
}
public SessionStateBehavior GetControllerSessionBehavior(RequestContext requestContext, string controllerName)
{
return defaultFactory.GetControllerSessionBehavior(requestContext, controllerName);
}
public void ReleaseController(IController controller)
{
defaultFactory.ReleaseController(controller);
}
}
As you can see, we're just using the default (Ninject) controller factory for most purposes unless it can't find the page. For obtaining the error controller, you can either pass in the kernel as you were already doing, or just call defaultFactory.CreateController using the error controller name.