HandleExceptionsAttribute Class

Handles exceptions thrown when processing controller's actions, ensures that internal exceptions are properly logged to the Event log.

Inheritance Hierarchy

System.Object
  System.Attribute
    FilterAttribute
      ExceptionFilterAttribute
        CMS.WebApi.HandleExceptionsAttribute

Namespace: CMS.WebApi
Assembly: CMS.WebApi (in CMS.WebApi.dll) Version: 9.0.0

Syntax

public class HandleExceptionsAttribute : ExceptionFilterAttribute

The HandleExceptionsAttribute type exposes the following members.

Constructors

	Name	Description
Public method	HandleExceptionsAttribute()	Creates new instance of HandleExceptionsAttribute.
Public method	HandleExceptionsAttribute(IEventLogService)	Creates new instance of HandleExceptionsAttribute

Methods

	Name	Description
Public method	OnException	Raises the exception event. (Overrides ExceptionFilterAttribute.OnException(HttpActionExecutedContext).)

Remarks

If exception is of type UnauthorizedAccessException, response is returned with the status code Unauthorized, so the browser can invoke login dialog. All other exceptions are logged to the Event log and empty response with status code InternalServerError is returned, except for the HttpResponseException. This exception is considered as valid result and therefore is returned to the caller, including the error message.

Examples

This example shows how to handle unauthorized request.

[HandleExceptions]
public class MyController : ApiController
{
    public HttpResponseMessage GetValue()
    {
        ...
        if(!IsAuthorized(MembershipContext.AuthenticatedUser))
        {
            // 401 status code Unauthorized is returned to the caller, so browser can handle the response properly
            throw new UnauthorizedAccessException();
        }
        ...
    }
}

This example shows how HttpResponseException behaves.

[HandleExceptions]
public class MyController : ApiController
{
    public HttpResponseMessage GetValue()
    {
        ...
        // 400 status code Bad request is returned to the caller together with the error message
        throw new HttpResponseException(Request.CreateErrorResponse(HttpStatusCode.BadRequest, "Given property is in invalid format"))
    }
}

This example shows how other types of exceptions behave.

[HandleExceptions]
public class MyController : ApiController
{
    public HttpResponseMessage GetValue()
    {
        ...
        // 500 status code Internal server error is returned to the caller. All sensitive data like error message or stack trace are omitted
        // Exception is logged to the Event log
        throw new Exception()
    }
}