I'm having trouble understanding why loads on my graphql mutation isn't working (no object found for ...).

[DennisMartinez]

Hey Everyone. I'm working through the mutations documentation, trying to implement the autoload arguments functionally using loads but the system is having trouble finding the object. I keep running into the following error:

"No object found for `userId: \"1\"`"

Here's my test mutation. It takes a user_id in, loads the user, and then returns the user.

module Mutations
  class AddUser < BaseMutation
    field :user, Types::UserType, null: false

    argument :user_id, ID, loads: Types::UserType

    def resolve(user:)
      { user: }
    end
  end
end

What's interesting, is, I can get it to work by adding this method to the AddUser mutation above. I don't know if that is correct or not as I'm not seeing it in the documentation examples (although mentioned).

def object_from_id(_type, global_id, _query_ctx)
  User.find(global_id)
end

Do I need to set object_from_id on every mutation? I may be misunderstanding what I need to do with this method. Anything else I should read up on in order to better understand why I can't load an object?

---

I've created a test repo with my issue https://github.com/DennisMartinez/graphql_mutation_test.

Documentation / issue reports I've read referenced in trying to understand this issue:

• https://graphql-ruby.org/schema/object_identification.html
• https://graphql-ruby.org/mutations/mutation_classes.html#auto-loading-arguments
• https://graphql-ruby.org/mutations/mutation_authorization.html#loading-and-authorizing-objects
• Mutation argument loads "No object found for..." error #3869. I couldn't get the proposed solution to work, but I did add a users query to the schema just in case.

Additional notes

• I've updated my resolve_type to acknowledge the UserType https://github.com/DennisMartinez/graphql_mutation_test/blob/master/app/graphql/graphql_mutation_test_schema.rb#L18
• I've applied the relay node to my user type https://github.com/DennisMartinez/graphql_mutation_test/blob/master/app/graphql/types/user_type.rb#L5

[rmosolgo]

Hi! Sorry for the trouble. By default, loads: uses the def self.object_from_id method defined on your Schema, which is here:

https://github.com/DennisMartinez/graphql_mutation_test/blob/86133c4adeb275a7d554a8a47bff12372ee15097/app/graphql/graphql_mutation_test_schema.rb#L38-L42

When you add def object_from_id to your mutation class, it overrides that method from the schema -- which is why it starts working again.

How about updating def self.object_from_id in the schema definition? I think that would make it work the way you expect. Give it a try and let me know what you find!

[DennisMartinez]

Hey @rmosolgo, thanks for the clarification! I see now what the problem was. I was overriding the id from the Node, which provides the global id. I was instead using the DB id. It looks like this is mentioned in the first sentence of the documentation 😅. I appreciate the help!

https://graphql-ruby.org/schema/object_identification.html#uuid-fields

module Types
  class UserType < Types::BaseObject
    implements GraphQL::Types::Relay::Node

    # field :id, ID, null: false <-- Problem
    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
  end
end