example_mongoose_model.js

module.exports = Mongoose => {
    const Schema = Mongoose.Schema

    const modelSchema = new Schema({
        name: {
            type: Schema.Types.String,
            trim: true
        },
        description: Schema.Types.String
    }, {
        timestamps: {
            createdAt: 'createdAt',
            updatedAt: 'updatedAt'
        }
    })

    // MIDDLEWARE ---------------------------------------------------------

    /**
     * Since most of the instance methods, static methods and virtual properties rely on the partition fields,
     * automatically populate the _fields reference to the field model documents for every find-like query
     */
    _.forEach( [ 'find', 'findOne', 'findOneById', 'findOneAndRemove', 'findOneAndUpdate' ], query => {
        modelSchema.pre( query, function( next ) {
            this.populate( '_fields' )
            next()
        })
    })

    // VIRTUAL PROPERTIES -------------------------------------------------

    /**
     * Retrieve the primary field for said partition
     *
     * @returns {object}    Returns the entire field, if the primary is true
     */
    modelSchema.virtual('primaryField').get(function() {
        const primary = _.find( this._fields, f => !!f.primary )

        return ! _.isEmpty( primary )
            ? primary
            : undefined
    })

    // INSTANCE METHODS ---------------------------------------------------

    /**
     * Verify an assets attribute value against the corresponding field settings in the assets partition
     *
     * @param   {object|string}     options         Object containing the attribute/field name & value, or the attribute
     *                                              name/field ID (Which if provided as a string, value will be
     *                                              automatically nulled, since it cant be defined anywhere else
     * @param   {function}          callback        Callback to be executed (if passed)
     * @var     {string}            options.attr    Name attribute or ID of field
     * @var     {Mixed}             options.value   Value of attribute (Null if undefined)
     * @var     {string|ObjectId}   options.assetId If the attribute value is being validated while updating the asset
     *                                              (as opposed to creating), then set the asset ID (This is required
     *                                              for some validations such as unique)
     * @returns {boolean}
     */
    modelSchema.methods.verifyAttr = function( options, callback ) {
        // .... removed
    }

    // --------------------------------------------------------------------

    /**
     * Retrieve select Partition Field ID's by the field names (ORM METHOD)
     *
     * @param   {string|array}  fieldNames      String of field names, or array of multiple.
     * @return  {object}        Object of field IDs and Names, with the field names as the keys
     */
    modelSchema.methods.getFieldIdsByName = function( fieldNames ) {
        // .... removed
    }
}