chore: Updated validator messages (#1133)

## Description

Improved validator messages to give error messages with null + when
checks.

## Related Issue(s)

[#1126](#1126)

## Verification

- [x] **Your** code builds clean without any errors or warnings
- [x] Manual testing done (required)
- [ ] Relevant automated test added (if you find this hard, leave it and
we'll help out)

## Documentation

- [ ] Documentation is updated (either in `docs`-directory, Altinnpedia
or a separate linked PR in
[altinn-studio-docs.](https://github.com/Altinn/altinn-studio-docs), if
applicable)


Co-authored-by: Amund Myrbostad <amund.myrbostad@digdir.no>

src/Digdir.Domain.Dialogporten.Application/Features/V1/EndUser/Dialogs/Queries/Search/SearchDialogQueryValidator.cs

@@ -2,6 +2,7 @@
 using Digdir.Domain.Dialogporten.Application.Common.Extensions.FluentValidation;
 using Digdir.Domain.Dialogporten.Application.Common.Pagination;
 using Digdir.Domain.Dialogporten.Application.Features.V1.Common.Localizations;
+using Digdir.Domain.Dialogporten.Domain.Common;
 using Digdir.Domain.Dialogporten.Domain.Localizations;
 using FluentValidation;
 
@@ -45,8 +46,8 @@ public SearchDialogQueryValidator()
             .When(x => x.ExtendedStatus is not null);
 
         RuleFor(x => x.Process)
-            .Must(x => Uri.IsWellFormedUriString(x, UriKind.Absolute))
-            .WithMessage("{PropertyName} must be a valid URI")
+            .IsValidUri()
+            .MaximumLength(Constants.DefaultMaxUriLength)
             .When(x => x.Process is not null);
 
         RuleForEach(x => x.Status).IsInEnum();

src/Digdir.Domain.Dialogporten.Application/Features/V1/ServiceOwner/DialogActivities/Queries/NotificationCondition/NotificationConditionValidator.cs

@@ -21,11 +21,12 @@ public NotificationConditionQueryValidator()
         RuleFor(x => x.TransmissionId)
             .NotNull()
             .NotEqual(default(Guid))
-            .When(x => x.ActivityType == DialogActivityType.Values.TransmissionOpened);
+            .When(x => x.ActivityType == DialogActivityType.Values.TransmissionOpened)
+            .WithMessage($"{{PropertyName}} must not be empty when ${nameof(NotificationConditionQuery.ActivityType)} is ${nameof(DialogActivityType.Values.TransmissionOpened)}");
 
         RuleFor(x => x.TransmissionId)
             .Null()
             .When(x => x.ActivityType == DialogActivityType.Values.DialogOpened)
-            .WithMessage($"{{PropertyName}} must be empty when {nameof(NotificationConditionQuery.ActivityType)} is {DialogActivityType.Values.DialogOpened}.");
+            .WithMessage($"{{PropertyName}} must be empty when {nameof(NotificationConditionQuery.ActivityType)} is {nameof(DialogActivityType.Values.DialogOpened)}.");
     }
 }

src/Digdir.Domain.Dialogporten.Application/Features/V1/ServiceOwner/Dialogs/Commands/Create/CreateDialogCommandValidator.cs

@@ -134,8 +134,8 @@ public CreateDialogCommandValidator(
             .SetValidator(activityValidator);
 
         RuleFor(x => x.Process)
-            .Must(x => Uri.IsWellFormedUriString(x, UriKind.Absolute))
-            .WithMessage("{PropertyName} must be a valid absolute URI.")
+            .IsValidUri()
+            .MaximumLength(Constants.DefaultMaxUriLength)
             .When(x => x.Process is not null);
 
         RuleFor(x => x.Process)
@@ -144,8 +144,8 @@ public CreateDialogCommandValidator(
             .When(x => x.PrecedingProcess is not null);
 
         RuleFor(x => x.PrecedingProcess)
-            .Must(x => Uri.IsWellFormedUriString(x, UriKind.Absolute))
-            .WithMessage("{PropertyName} must be a valid absolute URI.")
+            .IsValidUri()
+            .MaximumLength(Constants.DefaultMaxUriLength)
             .When(x => x.PrecedingProcess is not null);
     }
 }