HotChocolate GraphQL filtering on GUID

Question

I have very limited knowledge on GraphQL as I am still in the learning process. Now I stumbled upon an issue that I cannot resolve by myself without some help.

I'm using HotChocolate in my service.

I have a class ConsumerProductCategory with a Guid as Id which has a parent that is also a ConsumerProductCategory (think category > sub-category > ...)

Now I want to get the sub categories for a specific category, in linq you would write:

.Where(cat => cat.Parent.Id == id)

First of all lets start with our classes:

public class BaseViewModel : INode
{
    public virtual Guid Id { get; set; }
}


public class ConsumerProductCategory : BaseViewModel
{
    public ConsumerProductCategory()
    {
    }

    public string Name { get; set; }

    [UsePaging]
    [UseFiltering]
    [UseSorting]
    public List<ConsumerProduct> Products { get; set; } = new List<ConsumerProduct>();

    public ConsumerProductCategoryImage Image { get; set; }

    public ConsumerProductCategory Parent { get; set; } = null;

    public bool HasParent => this.Parent != null;
}

The object type definition is like this:

public class ConsumerProductCategoryType : ObjectType<ConsumerProductCategory>
{
    protected override void Configure(IObjectTypeDescriptor<ConsumerProductCategory> descriptor)
    {
        descriptor
            .Name(nameof(ConsumerProductCategory));

        descriptor
            .Description("Categories.");

        descriptor
            .Field(x => x.Id)
            //.Type<UuidType>()
            .Type<IdType>()
            .Description($"{nameof(ConsumerProductCategory)} Id.");

        descriptor
            .Field(x => x.Name)
            .Type<StringType>()
            .Description($"{nameof(ConsumerProductCategory)} name.");

        descriptor
            .Field(x => x.Parent)
            .Description($"{nameof(ConsumerProductCategory)} parent category.");

        descriptor
            .Field(x => x.Products)
            .Description($"{nameof(ConsumerProductCategory)} products.");

        descriptor
           .ImplementsNode()
           .IdField(t => t.Id)
           .ResolveNode((context, id) => context.Service<IConsumerProductCategoryService>().GetByIdAsync(id));
    }
}

The query to get the "main" categories would be like this:

query GetAllCategories {
  consumerProductCategories(
    #request: { searchTerm: "2"}
    first: 10
    after: null
    where: { hasParent: { eq: false } }
    order: {
      name: ASC
    }
  ) {
    nodes {
      id
      name
      image {
        url
        alt
      }
    }
    pageInfo {
      endCursor
      hasNextPage
    }
  }
}

This returns this result:

{
  "data": {
    "consumerProductCategories": {
      "nodes": [
        {
          "id": "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2EyOTYxNmRlMWMzMjQ4ZTU4YTU2YzRjYjdhMGQ5NmY5",
          "name": "Category 1",
          "image": {
            "url": "https://picsum.photos/200",
            "alt": "Category 1 Image"
          }
        },
        {
          "id": "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2NmZWI0YzNiMGQyNjQyOWI4MGU0MmQ1NGNjYWE1N2Q4",
          "name": "Category 2",
          "image": {
            "url": "https://picsum.photos/200",
            "alt": "Category 2 Image"
          }
        },
        {
          "id": "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2I0MjhjYWE2NGMxNTQ4MTdiMjM1ZWFhZWU3OGRhYWYz",
          "name": "Category 3",
          "image": {
            "url": "https://picsum.photos/200",
            "alt": "Category 3 Image"
          }
        }
      ],
      "pageInfo": {
        "endCursor": "Mg==",
        "hasNextPage": false
      }
    }
  }
}

The first thing I noticed was that the Id's (Guid's) are changed to some base64 encoded strings.

Weird, but if I would do this:

query {
      node(
        id: "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2EyOTYxNmRlMWMzMjQ4ZTU4YTU2YzRjYjdhMGQ5NmY5"
      ) {
        ... on ConsumerProductCategory {
          id
          name
        }
        
      }
    }

this perfectly works, result:

{
  "data": {
    "node": {
      "id": "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2EyOTYxNmRlMWMzMjQ4ZTU4YTU2YzRjYjdhMGQ5NmY5",
      "name": "Category 1"
    }
  }
}

However, now I want to filter on the Parent.Id,

query GetSubcategories {
  consumerProductCategories(    
    first: 10
    after: null
    where: { parent: { id: { eq: "Q29uc3VtZXJQcm9kdWN0Q2F0ZWdvcnkKZ2NmZWI0YzNiMGQyNjQyOWI4MGU0MmQ1NGNjYWE1N2Q4"}} }
    order: {
      name: ASC
    }
  ) {
    nodes {
      id
      name
      image {
        url
        alt
      }
      parent {
        id
      }
    }
    pageInfo {
      endCursor
      hasNextPage
    }
  }
}

This gives an error that the fieldtype where I do the "eq" is not correct, makes sense because in the data it's actually a Guid.

The result:

{
  "errors": [
    {
      "message": "The specified value type of field `eq` does not match the field type.",
      "locations": [
        {
          "line": 5,
          "column": 31
        }
      ],
      "path": [
        "consumerProductCategories"
      ],
      "extensions": {
        "fieldName": "eq",
        "fieldType": "UUID",
        "locationType": "UUID",
        "specifiedBy": "http://spec.graphql.org/June2018/#sec-Values-of-Correct-Type"
      }
    }
  ]
}

I understand why it gives me this error, but I have no clue how to resolve this.

I looked everywhere on Google but have not found a similar question and in the official docs of HotChocolate I cannot really find a solution for this issue.

Can anyone point me in the right direction?

By the way, is it a good practice to use these "autogenerated" base64 strings as Id's, or is there some way to specify that this generation should not happen and actually return the Guid's instead?

Thanks in advance!

score 0 · Answer 1 · answered Oct 06 '21 at 13:17

0

Ok, I can answer my own question, basically it isn't supported yet: github

What I've done for now is just add a second Guid in the base class:

This results in:

answered Oct 06 '21 at 13:17

HotChocolate GraphQL filtering on GUID

1 Answers1