export declare class FetchUtil {
    constructor();
    getProxyAgent(): any;
    fetchGetGeneric(url: string, headers?: any): Promise<string>;
    fetchGet(url: string, authToken?: string): Promise<string>;
    fetchDelete(url: string, authToken?: string): Promise<string>;
    fetchDeleteGeneric(url: string, headers?: string): Promise<string>;
    safeParseJSON(response: any): Promise<any>;
    fetchPatch(url: string, data: object, authToken?: string): Promise<string>;
    fetchPost(url: string, data: object, authToken?: string): Promise<string>;
    fetchPut(url: string, data: object, authToken?: string): Promise<string>;
    fetchPostGeneric(url: string, data: object, headers: object, resType?: any): Promise<string>;
    fetchPatchGeneric(url: string, data: object, headers: object): Promise<string>;
    fetchPutGeneric(url: string, data: object, headers: object): Promise<string>;
}