import { Metric } from "prom-client";
import { IMetricRegistry } from "./registry.interface";
export declare class GenericMetric implements IMetricRegistry {
    private register;
    constructor(labels?: {
        [key: string]: string;
    });
    metrics(): Promise<string>;
    get contentType(): "text/plain; version=0.0.4; charset=utf-8";
    addMetric(metric: Metric<any>): void;
    protected collectCustomMetrics(): void;
    collect(): (req: any, res: any, next: any) => void | Promise<void>;
}