Node Sequelize migrations/models is it possible to share the same code? - node.js

Question

I'm new at Sequelize so be patient.
I started up a new project using Sequelize
and migrations so I've got like this:
migrations/20150210104840-create-my-user.js:
"use strict";
module.exports = {
up: function(migration, DataTypes, done) {
migration.createTable("MyUsers", {
id: {
allowNull: false,
autoIncrement: true,
primaryKey: true,
type: DataTypes.INTEGER
},
first_name: {
type: DataTypes.STRING
},
last_name: {
type: DataTypes.STRING
},
bio: {
type: DataTypes.TEXT
},
createdAt: {
allowNull: false,
type: DataTypes.DATE
},
updatedAt: {
allowNull: false,
type: DataTypes.DATE
}
}).done(done);
},
down: function(migration, DataTypes, done) {
migration.dropTable("MyUsers").done(done);
}
};
models/myuser.js:
"use strict";
module.exports = function(sequelize, DataTypes) {
var MyUser = sequelize.define("MyUser", {
first_name: DataTypes.STRING,
last_name: DataTypes.STRING,
bio: DataTypes.TEXT
}, {
classMethods: {
associate: function(models) {
// associations can be defined here
}
}
});
return MyUser;
};
as you can see the table definition
is both on the migration and the model file.
I'm wondering if there is a way to share
the code ?
I mean I don't like to have logic in two files
if a field change I've to update twice.
UPDATE
following the Yan Foto example below
a different way may be cleaner.
schemas/users
'use strict';
module.exports = {
name: 'users',
definition : function(DataTypes) {
return {
id: {
type: DataTypes.INTEGER,
autoIncrement: true,
primaryKey: true
},
firstname: {
type:DataTypes.STRING
},
lastname: {
type:DataTypes.STRING
},
email: {
type: DataTypes.STRING,
unique: true
},
username: {
type:DataTypes.STRING,
unique: true
}
};
}
};
models/users
'use strict';
var Schema = require('../schemas/users');
module.exports = function(sequelize, DataTypes) {
return sequelize.define(
Schema.name,
Schema.definition(DataTypes),
{
freezeTableName: true ,
instanceMethods: {
countTasks: function() {
// how to implement this method ?
}
}
}
);
};
migrations/20150720184716-users.js
'use strict';
var Schema = require('../schemas/users');
module.exports = {
up: function (queryInterface, Sequelize) {
return queryInterface.createTable(
Schema.name,
Schema.definition(Sequelize)
);
},
down: function (queryInterface, Sequelize) {
return queryInterface.dropTable(Schema.name);
}
};

Answer 1

I wondered the same thing as I started using sequelize and here is my solution. I define my models as bellow:
module.exports = {
def: function(DataTypes) {
return {
id: {
type: DataTypes.INTEGER,
autoIncrement: true,
primaryKey: true
},
username: DataTypes.STRING,
password: DataTypes.STRING,
createdAt: DataTypes.DATE,
updatedAt: DataTypes.DATE,
}
},
config: {}
};
Where def defines the attributes and config is the optional options object accepted by define or migration methods. And I import them using the following code:
fs.readdirSync(__dirname + '/PATH/TO/models')
.filter(function(file) {
return (file.indexOf('.') !== 0) && (file !== basename);
})
.forEach(function(file) {
var name = file.substring(0, file.lastIndexOf(".")),
definition = require(path.join(__dirname + '/models', file));
sequelize['import'](name, function(sequelize, DataTypes) {
return sequelize.define(
name,
definition.def(DataTypes),
definition.config
);
});
});
For the migrations I have a similar approach:
const path = require('path');
module.exports = {
up: function (queryInterface, Sequelize) {
return queryInterface.createTable(
'users',
require(path.join(__dirname + '/PATH/TO/models', 'user.js')).def(Sequelize)
);
},
down: function (queryInterface, Sequelize) {
return queryInterface.dropTable('users');
}
};