objection-example.js

/*************** Migrations ***************/

exports.up = function(knex) {
  return knex.schema.withSchema('ObjectionTest')
    .createTable('Users', function (table) {
       table.increments('id')
       table.integer('user_email_id')
       table.string('address')
       table.verified('boolean')
       table.timestamp('created_at').defaultTo(knex.fn.now())
       table.timestamp('updated_at').defaultTo(knex.fn.now())
    })
    .createTable('UserSessions', function (table) {
       table.increments('id')
       table.integer('user_id')
       table.enum('user_type', ['admin', 'peasant'])
       table.string('session_id')
       table.timestamp('expires_at')
       table.timestamp('created_at').defaultTo(knex.fn.now())
       table.timestamp('updated_at').defaultTo(knex.fn.now())
    });
};

exports.down = function(knex) {
  return knex.schema.withSchema('ObjectionTest')
    .dropTable("Users")
    .dropTable("UserSessions");
};


/*************** Relational models ***************/

const SESSION_EXPIRES = 30 * DAYS

class UserSession extends Model {
  static get tableName() {
    return 'UserSessions';
  }
}

class User extends Model {
  static get tableName() {
    return 'Users';
  }

  static get relationMappings() {
    return {
      sessions: {
        relation: Model.HasManyRelation,
        modelClass: UserSession,

        // polymorphic relation for returns
        filter(builder) {
          builder.where('user_type', 'peasant')
        },

        // polymorphic relation for inserts
        beforeInsert(model) {
          model.user_type = 'peasant';
          model.expires_at = knex.fn.now() + SESSION_EXPIRES
          model.updated_at = knex.fn.now()
        },

        join: {
          from: 'Users.id',
          to: 'UserSessions.user_id'
        }
      }
    };
  }
}


/*************** Query examples ***************/

// new user
const user = await Person.query().insert({address})

// get user
const user = await User.query().where({address})

// verify user
const user = await Person.query().update({verified})

// Log in
user.$relatedQuery('sessions').insert({session_id: session.id})

// Log out
user.$relatedQuery('sessions').delete().where({session_id: session.id})

// Log out all devices
user.$relatedQuery('sessions').delete()