gatsby-node.js

// gatsby-node.js in my project root
/**
* So this shows up the index field in the graphiql explorer but when queried returns null
* even though this is present in my mdx field. Seems like I need to define the resolver somewhere
* but couldn't connect the dots
*/
exports.createSchemaCustomization = ({ actions, schema }) => {
  const { createTypes } = actions;
  createTypes(`type BlogPost implements Node @nodeInterface {
      date: Date @dateformat
      index: Int
  }`);

  createTypes(
    schema.buildObjectType({
      name: `MdxBlogPost`,
      fields: {
        date: { type: `Date`, extensions: { dateformat: {} } },
        index: { type: `Int` }
      },
      interfaces: [`Node`, `BlogPost`]
    })
  );
};