Data Annotated Model Validation Middleware for HotChocolate
$ dotnet add package DataAnnotatedModelValidationsData Annotated Model Validation Middleware for HotChocolate.
The purpose of this Middleware is to provide the same behavior as ASP.Net controllers, where all models would be
validated according to the specified Data Annotations or the IValidatableObject implementation; in essence it's always
on.
In addition, individual method arguments can be validated using annotations from System.ComponentModel.Annotations.
| HotChocolate Version | DataAnnotatedModelValidations Version | .NET Version |
|---|---|---|
| 15.0.3 or higher | 7.0.0 | .NET 8, 9 |
| 14.3.0 or higher | 6.3.0 | .NET 8, 9 |
| 14.2.0 or higher | 6.2.0 | .NET 8, 9 |
| 14.1.0 or higher | 6.1.0 | .NET 8, 9 |
| 14.0.0 or higher | 6.0.0 | .NET 8 |
| 13.9.0 or higher | 5.2.0 | .NET 6, 7, 8 |
| 13.7.0 or higher | 5.1.0 | .NET 6, 7, 8 |
| 13.7.0 or higher | 5.0.0 | .NET 6, 7, 8 |
| HotChocolate Version | Last DataAnnotatedModelValidations Version | .NET Version |
|---|---|---|
| 13.7.0 or higher | 4.2.0 | .NET 6, 7 |
| 12.16.0 or higher | 3.0.1 | .NET 7 |
| 12.4.1 or higher | 2.1.4 | .NET 6 |
📝For more information please visit
Locate your GraphQL Server registration and append .AddDataAnnotationsValidator()
ex.
// Startup.cs
public void ConfigureServices(IServiceCollection services)
{
// ...
services
.AddGraphQLServer()
.AddDataAnnotationsValidator()
.AddQueryType<Query>();
// ...
}To exclude a certain method argument from being validated just add the IgnoreModelValidation attribute.
ex.
public class Sample
{
[Required]
[MinLength(3)]
[EmailAddress]
public string? Email { get; set; }
}
public class Query
{
public string? GetTextIgnoreValidation([IgnoreModelValidation][MinLength(5)] string? text) => text;
public Sample? GetSampleIgnoreValidation([IgnoreModelValidation] Sample? sample) => sample;
}In C# one may define models in a multitude of ways.
To help alleviate potential issues consider the following:
public class Sample
{
[Required]
[MinLength(3)]
[EmailAddress]
public string? Email { get; set; }
}public record Sample
{
[Required]
[MinLength(3)]
[EmailAddress]
public string? Email { get; set; }
}The auto-property is initialized to the value of the corresponding primary constructor parameter. Attributes can be applied to the synthesized auto-property and its backing field by using
property:orfield:targets for attributes syntactically applied to the corresponding record parameter.
So per the documentation and following the guideline, a solution to the challenge mentioned would be adding the
property: prefix to the validation attribute.
public record Sample(
[property:Required]
[property:MinLength(3)]
[property:EmailAddress]
string? Email
);When implementing the IValidatableObject interface HotChocolate considers the Validate as a resolver; to avoid getting
schema errors said method needs to be ignored.
ex.
public class Sample : IValidatableObject
{
[Required]
[MinLength(3)]
[EmailAddress]
public string? Email { get; set; }
[GraphQLIgnore]
public IEnumerable<ValidationResult> Validate(ValidationContext validationContext) =>
Email?.StartsWith("no-property-name") == true
? new[] { new ValidationResult("no-property-name") }
: Enumerable.Empty<ValidationResult>();
}If you need to support numerical sequences in your validation results, consider adding the names as FieldName:[index].
The field name will be transformed in the error path as fieldName,_index_.
{
"errors": [
{
"message": "The field Count must be between 1 and 10.",
"path": [
"sample",
"obj",
"children",
"_2_",
"count"
],
"extensions": {
"code": "DAMV-400",
"field": "sample",
"type": "Mutation",
"specifiedBy": "https://spec.graphql.org/June2018/#sec-Values-of-Correct-Type"
}
}
]
}If you choose to omit the : character and add the names as FieldName[index] the field name and the index will be
represented as one entry, fieldName_index_.
{
"errors": [
{
"message": "The field Count must be between 1 and 10.",
"path": [
"sample",
"obj",
"children_2_",
"count"
],
"extensions": {
"code": "DAMV-400",
"field": "sample",
"type": "Mutation",
"specifiedBy": "https://spec.graphql.org/June2018/#sec-Values-of-Correct-Type"
}
}
]
}If multiple member names are added they will be treated as distinct error messages.
Ex. validation error '"Some validation error!"' was assigned to properties hello and world:
{
"errors": [
{
"message": "Some validation error!",
"path": [
"sample",
"obj",
"hello"
],
"extensions": {
"code": "DAMV-400",
"field": "sample",
"type": "Query",
"specifiedBy": "https://spec.graphql.org/June2018/#sec-Values-of-Correct-Type"
}
},
{
"message": "Some validation error!",
"path": [
"sample",
"obj",
"world"
],
"extensions": {
"code": "DAMV-400",
"field": "sample",
"type": "Query",
"specifiedBy": "https://spec.graphql.org/June2018/#sec-Values-of-Correct-Type"
}
}
],
"data": {
"sample": null
}
}If there is a need to express a nested relationship of a property and it's parent, consider adding the names separated
by a colon as ParentName:FieldName:[index]