Throw custom exception when validating specific action parameters

Question

I have to throw custom exceptions when validating properties, based on model state, in many of the actions the code is repetive.

How can this be refactored ?

Example of current code

[HttpGet("{jobId}/employeeLog")]
public async Task<IActionResult> GetFileLog(Guid jobId,
    [FromQuery] Guid employeeId,
    [SkipAndTopFromQuery] int? skip,
    [SkipAndTopFromQuery] int? top,
    [FromHeader(Name = "X-Correlation-ID")] string correlationId)
{
    var employeeIdToValidate = ModelState["employeeId"];
    var jobIdToValidate = ModelState["jobId"];
    if (employeeIdToValidate == null || employeeIdToValidate != null && employeeIdToValidate.Errors.Any())
        throw new InvalidFileIdException();
    if (jobIdToValidate == null || jobIdToValidate != null && jobIdToValidate.Errors.Any())
        throw new InvalidApplicationIdException();
    if (!ModelState.IsValid)
        return StatusCode((int)HttpStatusCode.BadRequest);

    ....
}

Vladyslav Yefremov · Accepted Answer · 2017-09-06 11:58:08Z

If you want to simplify your if statements, you can use Null Propagation Operator in C#

public async Task<IActionResult> GetFileLog(Guid jobId,
    [FromQuery] Guid employeeId,
    [SkipAndTopFromQuery] int? skip,
    [SkipAndTopFromQuery] int? top,
    [FromHeader(Name = "X-Correlation-ID")] string correlationId)
{
    var employeeIdToValidate = ModelState["employeeId"];
    var jobIdToValidate = ModelState["jobId"];

    if (employeeIdToValidate?.Errors?.Any() ?? true)
        throw new InvalidFileIdException();

    if (jobIdToValidate?.Errors?.Any() ?? true)
        throw new InvalidApplicationIdException();

    if (!ModelState.IsValid)
        return StatusCode((int)HttpStatusCode.BadRequest);

    ....
}

Also if your ModelState returns the same object, or object with common interface, you can move your checks into some method.

By the way, you can split your validation from your method by creating some sort of class like validator:

class GetFileLogValidatior: ValidatorBase {

    public override void Validate(GetFileLogValidatiorContext context) {

        var employeeIdToValidate = context.EmployeeIdToValidate;
        var jobIdToValidate = context.JobIdToValidate;

        if (employeeIdToValidate?.Errors?.Any() ?? true)
            throw new InvalidFileIdException();

        if (jobIdToValidate?.Errors?.Any() ?? true)
            throw new InvalidApplicationIdException();
    }

}

Collectives™ on Stack Overflow

Throw custom exception when validating specific action parameters

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related