Data Annotations on record fails in unittest

Question

Currently we are setting up a new project and like to use the new records introduced in C# 9. We encounter a problem with DataAnnotations inside the record (constructor) not being triggered during the unittest.

Now the DataAnnotation is triggered when calling the Controller, but when i try to simulate this in a unittest (see code below) it will never return any errors.

        //Unit Testing ASP.NET DataAnnotations validation
        //http://stackoverflow.com/questions/2167811/unit-testing-asp-net-dataannotations-validation
        protected static IList<ValidationResult> ValidateModel(object model)
        {
            var validationResults = new List<ValidationResult>();
            var ctx = new ValidationContext(model, null, null);
            Validator.TryValidateObject(model, ctx, validationResults, true);
            return validationResults;
        }

Currently we created a workaround:

    public record FooRecord(string BarProperty)
    {
        [Required]
        public string BarProperty { get; init; } = BarProperty;

    }

But I'm hoping if someone knows why this happens and maybe know how to solve this using the shorthand syntax:

    public record FooRecord([Required] BarProperty){ }

score 5 · Answer 1 · answered Apr 26 '21 at 14:27

5

It will work as expected if you define your record as:

public record FooRecord([property: Required] BarProperty){ }

answered Apr 26 '21 at 14:27

zeroid

701
7
19

I have `[StringLength]` attribute. I expect it should work same way. `property: ` gives the following error: `Record type 'AuthCodeRequest' has validation metadata defined on property 'AuthCode' that will be ignored. 'AuthCode' is a parameter in the record primary constructor and validation metadata must be associated with the constructor parameter` `param: ` and just `[StringLength]` works – SerjG Mar 04 '22 at 02:14
Also worked for MongoDb driver such as [property: Bson] – Reza Taba Dec 10 '22 at 23:14
same error as SerjG – Siarhei Kavaleuski Jul 13 '23 at 15:58

score 0 · Answer 2 · answered Mar 02 '23 at 13:21

Behavior of ASP.NET Core request parameters

You can't apply validation attributes [property: ... ] to your request parameters that undergoes binding & validation, see this question.

You will receive InvalidOperationException(...) like @SerjG describes in his comment.

It happend to me too and that is the reason why end up in this SO thread.

For details, see this issue.

Solution

Replace remove your validation attributes.
Use Fluent Validation instead.

Data Annotations on record fails in unittest

2 Answers2

Behavior of ASP.NET Core request parameters

Solution