Frontend <-> Backend Mapping

mapping.js

export default class HeardModel extends AbstractModel {
    @ApiField('ApiConfidence')
    private confidence: string = '';

    @ApiField('heardType')
    private type: string = '';

    @ApiField('tradedOnDate', (dateString: string) => new Date(dateString), (date: Date) => date.getTime())
    private traded: Date = new Date();
}



export default abstract class AbstractModel {
    abstract fromApi(object) {
        _.forEach(this.apiFieldsBag, (fieldObject, key) => {
            this[key] = fieldObject.setFn(object[fieldObject.apiKey]);
        });
    }

    abstract toApi() {
        const ret = {};

        _.forEach(this.apiFieldsBag, (fieldObject, key) => {
            ret[fieldObject.apiKey] = fieldObject.getFn(this[key]);
        });

        return ret;
    }
}


export default function ApiField(apiKey: string, setFn, getFn) {
    return (target: Object, propertyKey: string, descriptor: TypedPropertyDescriptor<any>) => {
        target.apiFieldsBag = target.apiFieldsBag || {};
        target.apiFieldsBag[propertyKey] = {
            apiKey: apiKey,
            setFn: setFn || ((ret) => ret),
            getFn: getFn || ((ret) => ret)
        };
        return descriptor;
    };
}