adding functions to a knex/bookshelf model in node/express - node.js

Question

I have a model like this:
const User = db.Model.extend({
tableName: 'users',
hasSecurePassword: true
});
module.exports = User;
With this I can do things like
const User = require("../models/user");
User.fetchAll({columns:['id','email']}).then((data) => {
res.json(data);
}).catch(err => {
res.json(err);
});
What if I want to add costume functions to my model such as:
var connection = require('./dbconnection.js');
var User = db.Model.extend({
tableName: 'users',
hasSecurePassword: true
});
User.getUsers = (callback) => {
if (connection) {
const newLocal = "select * FROM users";
connection.query(newLocal, (err,rows,fields) => {
if (err) {
return res.sendStatus(500);
} else {
callback(null,rows);
}
});
}
};
module.exports = User;
And then do something like:
const User = require("../models/user");
User.getUsers((err,data) => {
res.status(200).json(data);
});
Is this posible? Or should I just conform with the bookshelf functions?
Right now the error I get is connection.query is not a function
And models/dbconnection.js is:
const mysql = require('mysql');
port = process.env.PORT || 3333;
if (port == 3333) {
var connection = mysql.createConnection({
host: process.env.DB_HOST,
port: process.env.DB_PORT,
user: process.env.DB_USER,
password: process.env.DB_PASSWORD,
database: process.env.DB_NAME,
insecureAuth: true
});
} else {
console.log("Error");
}
connection.connect();
module.exports.connection = connection;

Answer 1

Yes, you can add your custom functions to bookshelf models in two different ways.
Instance methods
For example, you want to return user's full name, your User model will look something like this
const User = db.Model.extend({
tableName: 'users',
hasSecurePassword: true,
//be careful here, if you use arrow function `this` context will change
//and your function won't work as expected
returnFullName: function() {
return this.get('firstname') + this.get('lastname');
}
});
module.exports = User;
then you will call this function like this
User.forge().where({id: SOME_ID}).fetch()
.then(function(user) {
var fullName = user.returnFullName();
});
Class methods
For example, you want to return user's email based on username, your User model will look something like this
const User = db.Model.extend({
tableName: 'users',
hasSecurePassword: true
}, {
getUserEmail: function(SOME_USERNAME) {
return User.forge().where({username: SOME_USERNAME}).fetch()
.then(function (user) {
if(user) {
return Promise.resolve(user.get('email'));
} else {
return Promise.resolve(null);
}
});
}
});
module.exports = User;
then you can call this function like
User.getUserEmail(SOME_USERNAME)
.then(function(email) {
console.log(email);
});