salix/services/loopback/common/methods/sale/priceDifference.js

module.exports = Self => {
    Self.remoteMethod('priceDifference', {
        description: 'Returns a sale price difference',
        accessType: 'READ',
        accepts: [{
            arg: 'ticketFk',
            type: 'number',
            required: true,
            description: 'ticket id',
            http: {source: 'path'}
        }],
        returns: {
            type: ['Object'],
            root: true
        },
        http: {
            path: `/:ticketFk/priceDifference`,
            verb: 'GET'
        }
    });

    Self.priceDifference = async ticketFk => {
        let filter = {
            where: {
                ticketFk: ticketFk
            },
            order: 'concept ASC',
            include: [{
                relation: 'item',
                scope: {
                    include: {
                        relation: 'tags',
                        scope: {
                            fields: ['tagFk', 'value'],
                            include: {
                                relation: 'tag',
                                scope: {
                                    fields: ['name']
                                }
                            },
                            limit: 6
                        }
                    },
                    fields: ['itemFk', 'name']
                }
            }]
        };

        return await Self.find(filter);
    };
};