Add example for model relations

Can somebody show an example of creating relations between the models?

I want to relate a model Tutorial and Comment. How can i do that?

I make it so:

'use strict'

const Sequelize = require('sequelize')

module.exports = function (sequelize) {
  const comment = sequelize.define('comment', {
    content: {
      required: true,
      type: Sequelize.TEXT,
      allowNull: false
    },
    tutorialId: {
      required: true,
      type: Sequelize.INTEGER
    }
  }, {
    timestamps: true,
    freezeTableName: true
  })

  comment.belongsTo(sequelize.models.tutorial)

  comment.sync({
    force: true
  })

  return comment
}

But sometimes, when i start my application i have error:

Unhandled rejection SequelizeDatabaseError: relation "tutorial" does not exist

I used to work only with mongoDB. But I think I need to learn sequelize.

It would be great if we had more examples that show how to work with the database, how to set up the relationship between models and between services. I read the documentation, but it very much and I’m not like I can not configure it to work properly.

[lopezjurip]

My current approach:

// src/services/organization/organization-model.js

const Sequelize = require('sequelize');

module.exports = function(sequelize) {
  const organization = sequelize.define('organization', {
    name: {
      type: Sequelize.STRING,
      allowNull: false,
    },
  }, {
    classMethods: {
      associate(models) {
        organization.hasMany(models.user);
      },
    },
  });

  return organization;
};

// src/services/index.js

const Sequelize = require('sequelize');

const authentication = require('./authentication');
const user = require('./user');
const organization = require('./organization');

module.exports = function() {
  const app = this;

  const sequelize = new Sequelize(app.get('postgres'), {
    dialect: 'postgres',
    logging: false, // console.log,
  });
  app.set('sequelize', sequelize);

  app.configure(authentication);
  app.configure(user);
  app.configure(organization);

  // Setup relationships
  const models = sequelize.models;
  Object.values(models)
    .filter(model => model.associate)
    .forEach(model => model.associate(models));

  sequelize.sync();
};

[kulakowka]

It seems I figured.