Deserialize JSON to typscript object

Allows you to parse JSON throwing errors on undefined or null properties.

e.g. following typescript Todo class:

export class Todo implements Deserializable{
    public id: number = 0;
    public description: string = "";
    public isDone: boolean = false;

    constructor(){

    }
}

This class has default values, but if we parse it from JSON, values can still be null or undefined. This a pain writing APIs in typescript.

To solve this, implement Deserializable using DeserializeUtil:

import { Deserializable, DeserializeUtil } from "deserialize-json-strict";

export class Todo implements Deserializable{

    ...

    public deserialize(values:any) {
        this.id = DeserializeUtil.StrictNumber(values.id);
        this.description = DeserializeUtil.StrictString(values.description);
        this.isDone = DeserializeUtil.StrictBoolean(values.isDone);
    }
}

To create typescript class instance:

export async function create(req: Request, resp: Response) {
    let data = req.body;
    let todo = new Todo();

    try{
        todo.deserialize(data);
    }catch(error){
        resp.sendStatus(400);
    }
}

This rejects undefined and null as API arguments, still allowing empty values.