Se agrega un convertidor para convertir de Json a UserEntity y viceversa

import { UserRole } from "../../constants/roles";

export interface UserEntity {

    name?: string;

    name: string;

    lastName?: string;

    email: string;

    role: UserRole;

    lastName?: string;

    email: string;

}

export class Convert {

    public static toUser(json: string): UserEntity {

        return cast(JSON.parse(json), r("User"));

    }

    public static userToJson(value: UserEntity): string {

        return JSON.stringify(uncast(value, r("User")), null, 2);

    }

}

function invalidValue(typ: any, val: any, key: any, parent: any = ''): never {

    const prettyTyp = prettyTypeName(typ);

    const parentText = parent ? ` on ${parent}` : '';

    const keyText = key ? ` for key "${key}"` : '';

    throw Error(`Invalid value${keyText}${parentText}. Expected ${prettyTyp} but got ${JSON.stringify(val)}`);

}

function prettyTypeName(typ: any): string {

    if (Array.isArray(typ)) {

        if (typ.length === 2 && typ[0] === undefined) {

            return `an optional ${prettyTypeName(typ[1])}`;

        } else {

            return `one of [${typ.map(a => { return prettyTypeName(a); }).join(", ")}]`;

        }

    } else if (typeof typ === "object" && typ.literal !== undefined) {

        return typ.literal;

    } else {

        return typeof typ;

    }

}

function jsonToJSProps(typ: any): any {

    if (typ.jsonToJS === undefined) {

        const map: any = {};

        typ.props.forEach((p: any) => map[p.json] = { key: p.js, typ: p.typ });

        typ.jsonToJS = map;

    }

    return typ.jsonToJS;

}

function jsToJSONProps(typ: any): any {

    if (typ.jsToJSON === undefined) {

        const map: any = {};

        typ.props.forEach((p: any) => map[p.js] = { key: p.json, typ: p.typ });

        typ.jsToJSON = map;

    }

    return typ.jsToJSON;

}

function transform(val: any, typ: any, getProps: any, key: any = '', parent: any = ''): any {

    function transformPrimitive(typ: string, val: any): any {

        if (typeof typ === typeof val) return val;

        return invalidValue(typ, val, key, parent);

    }

    function transformUnion(typs: any[], val: any): any {

        // val must validate against one typ in typs

        const l = typs.length;

        for (let i = 0; i < l; i++) {

            const typ = typs[i];

            try {

                return transform(val, typ, getProps);

            } catch (_) {}

        }

        return invalidValue(typs, val, key, parent);

    }

    function transformEnum(cases: string[], val: any): any {

        if (cases.indexOf(val) !== -1) return val;

        return invalidValue(cases.map(a => { return l(a); }), val, key, parent);

    }

    function transformArray(typ: any, val: any): any {

        // val must be an array with no invalid elements

        if (!Array.isArray(val)) return invalidValue(l("array"), val, key, parent);

        return val.map(el => transform(el, typ, getProps));

    }

    function transformDate(val: any): any {

        if (val === null) {

            return null;

        }

        const d = new Date(val);

        if (isNaN(d.valueOf())) {

            return invalidValue(l("Date"), val, key, parent);

        }

        return d;

    }

    function transformObject(props: { [k: string]: any }, additional: any, val: any): any {

        if (val === null || typeof val !== "object" || Array.isArray(val)) {

            return invalidValue(l(ref || "object"), val, key, parent);

        }

        const result: any = {};

        Object.getOwnPropertyNames(props).forEach(key => {

            const prop = props[key];

            const v = Object.prototype.hasOwnProperty.call(val, key) ? val[key] : undefined;

            result[prop.key] = transform(v, prop.typ, getProps, key, ref);

        });

        Object.getOwnPropertyNames(val).forEach(key => {

            if (!Object.prototype.hasOwnProperty.call(props, key)) {

                result[key] = transform(val[key], additional, getProps, key, ref);

            }

        });

        return result;

    }

    if (typ === "any") return val;

    if (typ === null) {

        if (val === null) return val;

        return invalidValue(typ, val, key, parent);

    }

    if (typ === false) return invalidValue(typ, val, key, parent);

    let ref: any = undefined;

    while (typeof typ === "object" && typ.ref !== undefined) {

        ref = typ.ref;

        typ = typeMap[typ.ref];

    }

    if (Array.isArray(typ)) return transformEnum(typ, val);

    if (typeof typ === "object") {

        return typ.hasOwnProperty("unionMembers") ? transformUnion(typ.unionMembers, val)

            : typ.hasOwnProperty("arrayItems")    ? transformArray(typ.arrayItems, val)

            : typ.hasOwnProperty("props")         ? transformObject(getProps(typ), typ.additional, val)

            : invalidValue(typ, val, key, parent);

    }

    // Numbers can be parsed by Date but shouldn't be.

    if (typ === Date && typeof val !== "number") return transformDate(val);

    return transformPrimitive(typ, val);

}

function cast<T>(val: any, typ: any): T {

    return transform(val, typ, jsonToJSProps);

}

function uncast<T>(val: T, typ: any): any {

    return transform(val, typ, jsToJSONProps);

}

function l(typ: any) {

    return { literal: typ };

}

function a(typ: any) {

    return { arrayItems: typ };

}

function u(...typs: any[]) {

    return { unionMembers: typs };

}

function o(props: any[], additional: any) {

    return { props, additional };

}

function m(additional: any) {

    return { props: [], additional };

}

function r(name: string) {

    return { ref: name };

}

const typeMap: any = {

    "User": o([

        { json: "email", js: "email", typ: "" },

        { json: "name", js: "name", typ: "" },

        { json: "role", js: "role", typ: "" },

    ], false),

};