Not sure if an issue or maybe something I'm not getting:

[oviava]

module.exports = (sequelize, DataTypes) => {
  let Speaker = sequelize.define('Speaker', { // eslint-disable-line
    name: { type: DataTypes.STRING(128), allowNull: false }, // eslint-disable-line
    description: DataTypes.STRING,
    position: DataTypes.STRING(128), // eslint-disable-line
    company: DataTypes.STRING(128), // eslint-disable-line
  }, {
    classMethods: {
      associate: (models) => {
        Speaker.Presentations = Speaker.hasMany(models.Presentation, { as: 'presentations' });
      },
    },
  });

  return Speaker;
};

module.exports = (sequelize, DataTypes) => {
  const Presentation = sequelize.define('Presentation', {
    title: { type: DataTypes.STRING(128), allowNull: false }, // eslint-disable-line
    description: DataTypes.STRING,
  }, {
    classMethods: {
      associate: (models) => {
        Presentation.Speaker = Presentation.belongsTo(models.Speaker, {
          as: 'speaker',
          foreignKey: 'speakerId',
          onDelete: 'CASCADE',
        });
      },
    },
  });

  return Presentation;
};

'use strict';

const fs = require('fs');
const path = require('path');
const Sequelize = require('sequelize');
const sequelize = new Sequelize('xxxxx', 'xxxxx', 'xxxxx', {
  host: 'localhost',
  dialect: 'mariadb',
});

let db = {};

fs
  .readdirSync(__dirname)
  .filter((file) => (file.indexOf('.') !== 0) && (file !== 'index.js'))
  .forEach((file) => {
    const model = sequelize.import(path.join(__dirname, file));
    db[model.name] = model;
  });

Object.keys(db).forEach((modelName) => {
  if ('associate' in db[modelName]) {
    db[modelName].associate(db);
  }
});

db.sequelize = sequelize;
db.Sequelize = Sequelize;

module.exports = db;

import { resolver } from 'graphql-sequelize';
import {
  GraphQLObjectType,
  GraphQLNonNull,
  GraphQLString,
  GraphQLInt,
} from 'graphql';

import { Presentation } from '../models';
import speakerType from './speakerType';


const presentationType = new GraphQLObjectType({
  name: 'Presentation',
  description: 'A Presentation',
  fields: {
    id: {
      type: new GraphQLNonNull(GraphQLInt),
      description: 'Presentation Id',
    },
    title: {
      type: new GraphQLNonNull(GraphQLString),
      description: 'Presentation Title',
    },
    description: {
      type: GraphQLString,
      description: 'Presentation Description',
    },
    speaker: {
      type: speakerType,
      resolve: resolver(Presentation.Speaker),
    },
  },
});

export default presentationType;

error:

Error: Presentation.speaker field type must be Output Type but got: undefined.

Can't seem to get references to work

[mickhansen]

The resolver is not your issue, the type for speaker is undefined, try logging speakerType

[oviava]

think I found it ... just assumed that was ok:

https://gist.github.com/xicombd/77406c29ddf37fe46c3c

[oviava]

Closed. Thank you Mick, fyi for anyone else who might encounter this.