medici/packages/core/src/xhr.ts

export interface BrowserTransportOptions {
    url: string;
    data: any;
}

export const makeXHRRequest = (options: BrowserTransportOptions): Promise<XMLHttpRequestResponseType> => {
    return new Promise((resolve, reject) => {
        const xhr = new XMLHttpRequest();
        xhr.open('POST', options.url, true);
        xhr.setRequestHeader('Content-Type', 'application/json');
        xhr.onerror = reject;
        xhr.onreadystatechange = (): void => {
            if (xhr.readyState === 4) {
                resolve(xhr.response);
            }
        };
        xhr.send(JSON.stringify(options.data));
    });
};