salix/services/ticket/common/methods/ticket-tracking/changeState.js

const UserError = require('vn-loopback/common/helpers').UserError;

module.exports = Self => {
    Self.remoteMethod('changeState', {
        description: 'Change the state of a ticket',
        accessType: 'WRITE',
        accepts: [{
            arg: 'params',
            type: 'object',
            required: true,
            description: 'ticketFk',
            http: {source: 'body'}
        }],
        returns: {
            type: 'string',
            root: true
        },
        http: {
            path: `/changeState`,
            verb: 'post'
        }
    });

    Self.changeState = async params => {
        let isEditable = await Self.app.models.Ticket.isEditable(params.ticketFk);
        if (isEditable)
            return await Self.app.models.TicketTracking.create(params);

        throw new UserError(`You don't have enough privileges to change the state of this ticket`);
    };
};