类型上不存在 Graphql 字段

Question

After skimming through the docs of Graphql I've started to implement it on a toy rails\/reactJS project. The projects allows an user to sign in through devise then access a dummy \/artist route that displays a list of artists. Everything seems to work fine until I try to consume api data with GraphQL from the react app to get artists and display them.

class GraphqlController < ApiController
  rescue_from Errors::Unauthorized do |exception|
    render json: {errors: ['Unauthorized.']}, status: :unauthorized
  end

  def index
    result = Schema.execute params[:query], variables: params[:variables], context: context
    render json: result, status: result['errors'] ? 422 : 200
  end

private

  def context
    token, options = ActionController::HttpAuthentication::Token.token_and_options request
    {
      ip_address: request.remote_ip
    }
  end
end

Answer 1

I don't think this is the issue for this particular case, but I was getting this error and it turned out to be due to a simple syntax error. Query attributes need to be in camelCase format, not under_score format. Maybe this will help someone else that lands here when searching for this error like I did.

Answer 2

The GQL query you sent is malformed, it is asking for the query field of Query root object. Use this instead:

const artistListQuery = gql`
    query UseTheNameYouWantHere {
        artists {
            id
            name
            description     
        }
    }
`;

BTW, you can add graphiql gem ( https://github.com/rmosolgo/graphiql-rails ) to have a playground with your GraphQL API.

Answer 3

All right, the problem is not in the code itself. I changed the query to the one you adviced and updated the name artists to something else on both client and server side. It seems like apollo-rails is caching previous api calls, even if they failed, that why I was always getting the same error. I still have to figure out how to clean this cache. Thanks for your time.

Answer 4

I had this error in RSpec , but not in a real call, ie Postman, for the same query. The solution was to change the query in spec from

<<~QUERY
  query users {
    posts {
      ...
    }
  }
QUERY

to

<<~QUERY
  query users {
    users {
      posts {
        ...
      }
    }
  }
QUERY

However in other specs, the first approach was working with similarly looking mutation, so I am not sure what was wrong

Answer 5

In my case the issue was that I had a structure like this:

module Types
  class SomeType < Types::BaseObject
    field :comparator,
          Types::ComparatorType
    field :options,
          [Types::OptionType]
  end
end

BUT in the query I had other nested structure called data that I forgot about:

mutation {
  myMutation(
    ...  
  ) {
    someType {
      comparator {
        ...
      }
      data {
        options {
           ...
        }
      }
    }
  }
}

So after changing SomeType class to add that missing key solved my issue. So now it look like this:

module Types
  class SomeType < Types::BaseObject
    field :comparator,
          Types::ComparatorType
    field :data,
          Types::DataType
  end
end

# New file
module Types
  class DataType < Types::BaseObject
    field :options,
          [Types::OptionType]
  end
end

Answer 6

You might need to use a newer API endpoint URL version.