Sequelize not generating join table or get/add methods - node.js

Question

I run node 10.16.3 and sequelize 5.19.5. I created two models with a many to many relationship between them, using sequelize model:generate. It created both model and migration files. Supposedly, when I specify a many to many association, sequelize should generate the join table by itself, and also generate add methods on those models, so I can associate them properly. None of those things happened in my case after I ran sequelize db:migrate and sequelize db:seed:all. I saw many people just creating a join table manually, but I'd like to avoid that if there's a simpler way. Code files follow (with omitted imports for some constants that are irrelevant):
model Activity
module.exports = (sequelize, DataTypes) => {
const Activity = sequelize.define('Activity', {
name: DataTypes.ENUM(cleaningActivity),
category: DataTypes.STRING,
baseRate: DataTypes.FLOAT,
specialEquipment: DataTypes.STRING,
description: DataTypes.STRING,
deleted: DataTypes.BOOLEAN
}, {});
Activity.associate = function(models) {
Activity.belongsToMany(models.ActivityBundle, {
through: 'Activity_ActivityBundle'
});
};
return Activity;
};
Activity migration:
module.exports = {
up: (queryInterface, Sequelize) => {
return queryInterface.createTable('Activity', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
name: {
type: Sequelize.ENUM(cleaningActivity)
},
category: {
type: Sequelize.STRING
},
baseRate: {
type: Sequelize.FLOAT
},
specialEquipment: {
type: Sequelize.STRING
},
description: {
type: Sequelize.STRING
},
deleted: {
type: Sequelize.BOOLEAN
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE
}
});
},
down: (queryInterface, Sequelize) => {
return queryInterface.dropTable('Activity');
}
};
Now, ActivityBundle model:
module.exports = (sequelize, DataTypes) => {
const ActivityBundle = sequelize.define('ActivityBundle', {
name: DataTypes.ENUM(cleaningBundle),
deleted: DataTypes.BOOLEAN
}, {});
ActivityBundle.associate = function(models) {
ActivityBundle.belongsToMany(models.Activity, {
through: 'Activity_ActivityBundle'
});
};
return ActivityBundle;
};
and finally, ActivityBundle migration:
module.exports = {
up: (queryInterface, Sequelize) => {
return queryInterface.createTable('ActivityBundle', {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: Sequelize.INTEGER
},
name: {
type: Sequelize.ENUM(cleaningBundle)
},
deleted: {
type: Sequelize.BOOLEAN
},
createdAt: {
allowNull: false,
type: Sequelize.DATE
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE
}
});
},
down: (queryInterface, Sequelize) => {
return queryInterface.dropTable('ActivityBundle');
}
};
Then, I have a seed file, where I ma trying to first create bundles, then associate them to activities, like so:
module.exports = {
up: async (queryInterface, Sequelize) => {
const bundles = await ActivityBundle.bulkCreate(bundlesArray);
return Activity.bulkCreate(activitiesArray).then(activities => {
return Promise.all(activities.map(activity => {
const bundlesPerActivity = activityBundleMapping[activity.get('name')]
.map(name => bundles.find(b => b.get('name') === name));
return activity.addBundles(bundlesPerActivity); // this method does not exist, even though it should
}));
})
},
down: (queryInterface, Sequelize) => {
}
};
Clearly I am doing something wrong. What more am I supposed to define and where? I guess the migration files need to have some mention of many to many association? Not a clue, and official documentation is incomplete imho.

Answer 1

You need to generate the join table yourself. Sequelize isn't that magical. :)
module.exports = {
up: (queryInterface, Sequelize) => {
return queryInterface.createTable(
'Activity_ActivityBundle',
{
createdAt: {
allowNull: false,
type: Sequelize.DATE,
},
updatedAt: {
allowNull: false,
type: Sequelize.DATE,
},
ActivityId: {
type: Sequelize.INTEGER,
primaryKey: true,
},
ActivityBundleId: {
type: Sequelize.INTEGER,
primaryKey: true,
},
}
);
},
down: (queryInterface, Sequelize) => {
// remove table
return queryInterface.dropTable('Activity_ActivityBundle');
},
};