function defineAttachment(sequelize, DataTypes) { const Attachment = sequelize.define('Attachment', { title: { type: DataTypes.STRING, allowNull: false, }, detail: { type: DataTypes.STRING, allowNull: true, }, path: { type: DataTypes.STRING, allowNull: false, }, }); Attachment.associate = (models) => { Attachment.belongsToMany(models.Case, { through: 'caseAttachments', }); }; return Attachment; } module.exports = defineAttachment;