flex-mapper

TypeScript library for mapping objects and classes.

Usage

Installation:

npm i flex-mapper

• map function
• map class
• mapProperty decorator
• mapConvert decorator

map function

Maps objects

import { map } from 'flex-mapper';

...

const cat = {
    name: "Tom",
    color: "gray",
    years: 2
}
const result = map(cat, {
    name: 'nickname',
    color: value => value.toUpperCase(),
    years: [value => value * 12, "months"]
});
console.info(result);
// {
//     nickname: "Tom",
//     color: "GRAY",
//     months: 24
// }

map class

Destination class definition. Mapping options are described with decorators: @mapProperty and @mapConvert.

import { mapProperty, mapConvert } from 'flex-mapper';

...

class CatClass {
    @mapProperty("name")
    nickname: number;

    @mapConvert(value => value.toUpperCase())
    color: string;

    @mapProperty("years", value => value * 12)
    months: number;
}

Mapping class object:

import { map } from 'flex-mapper';

...

const cat = {
    name: "Tom",
    color: "gray",
    years: 2
}
const result = map(cat, CatClass);
console.info(result);
// {
//     nickname: "Tom",
//     color: "GRAY",
//     months: 24
// }

This is important to pass the class type as a second parameter. In this way map method reads decorators defined inside the class.

mapProperty decorator

Describes how the property is to be mapped.

Parameter is an interface with properties:

Name	Type	Description
source	string	Source property name
convert	function or string	In function case, parameter is source value the function result is definition value. In string case, possible values are: number, string.

mapConvert decorator

Has one function or string parameter for converting.