Remove Try/Catch statements from asp.net controllers

Question

I have an Asp.Net core 3.1 Web Api project in witch I have a lot of controllers.

almost in every controller I have a template like this:

public class SomeController:ControllerBase

{
    //injecting my service

    [HttpGet]
    [Route("")]
    public async Task<ActionResult> SomeMethod()

        {
            try
            {
               //Do some work
               return Ok(somevalue);
            }
            
            catch(ServiceException ex)
            {
              return BadRequest(ex.Message);
            }
            catch
            {
              return BadRequest();
            }
        }
}

this template is implemented in almost all the controllers.

I want to delete try...catch statements and write a base class or something to handle this try...catch statements outside my controller.

something like this I reckon:

public async Task<ActionResult> SomeMethod()

    {
       //Do some work
       
       return Ok(somevalue);
       //if any exception of ServiceException type occured i want to 
       //return BadRequest with message and if not a BadRequest without message
    }

I have heard something about Cross-Cutting Concerns but I don't know how to use them.

Do you have any Idea how can I do it?

Bad Request is an input validation response. Returning it in response to caught exceptions is telling the caller the wrong thing (unless your input validation throws exceptions). — madreflection, Apr 29 '22 at 16:41
It sounds more like this would be suitable to move this into middleware, where you could also specify controllers that do not follow this pattern eg. through attributes. — ekke, Apr 29 '22 at 16:43
Yes, move it to middleware, but return a 500 Internal Server Error instead of 400 Bad Request. — madreflection, Apr 29 '22 at 16:49

score 4 · Accepted Answer · answered Apr 29 '22 at 16:44

Absolutely agree, anything that has try/catch implemented everywhere is a code smell and there's a better way of doing things.

If you search for 'Global Exception Handling netcore' you'll find a lot of hits on this subject.

In general, let the exception propagate up the stack, preserve all the exception detail and let it be caught and handled by a Middleware. Probably a bit too much code to snippet into this answer, but here's decent article with a couple of different versions/examples available

https://jasonwatmore.com/post/2022/01/17/net-6-global-error-handler-tutorial-with-example

You'll notice returning responses from the middleware, and this is your opportunity to perform logging centrally as well - a single place to capture and log all your exception details.

Agree with the approach suggested in this blog post. Just remember to log the exception too. Catching an exception like this and overriding the response will cause other exception-logging middleware to not get notified — ThomasArdal, Apr 30 '22 at 07:53

score 1 · Answer 2 · answered Apr 29 '22 at 16:47

1

A simple approach:

public static ActionResult Try(Func<ActionResult> action)
{
    try
    {
        return action();
    }
    catch (ServiceException ex)
    {
        return BadRequest(ex.Message);
    }
    catch
    {
        return BadRequest();
    }
}

And you use like:

return Try(() => Ok(someValue));

Or

return Try(() => 
{
    // Do something...
    return new EmptyResult();
});

answered Apr 29 '22 at 16:47

Victor

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Seems good. i will try it – Ali.Rashidi Apr 29 '22 at 17:40

Remove Try/Catch statements from asp.net controllers

2 Answers2