/// <reference types="node" />
import * as events from 'events';
import { Configuration, FeatureConfig, Variation } from './openapi';
import { Options, Target } from './types';
import { AxiosInstance } from 'axios';
export declare enum MetricEvent {
    READY = "metrics_ready",
    ERROR = "metrics_error"
}
export interface MetricsProcessorInterface {
    start(): void;
    close(): void;
    enqueue(target: Target, featureConfig: FeatureConfig, variation: Variation): void;
}
export declare class MetricsProcessor implements MetricsProcessorInterface {
    private environment;
    private cluster;
    private conf;
    private options;
    private eventBus;
    private closed;
    private httpsClient;
    private evaluationAnalytics;
    private targetAnalytics;
    private seenTargets;
    private MAX_EVALUATION_ANALYTICS_SIZE;
    private MAX_TARGET_ANALYTICS_SIZE;
    private evaluationAnalyticsExceeded;
    private targetAnalyticsExceeded;
    private syncInterval?;
    private api;
    private readonly log;
    constructor(environment: string, cluster: string, conf: Configuration, options: Options, eventBus: events.EventEmitter, closed: boolean, httpsClient: AxiosInstance);
    start(): void;
    close(): void;
    enqueue(target: Target, featureConfig: FeatureConfig, variation: Variation): void;
    private storeTargetAnalytic;
    private storeEvaluationAnalytic;
    private _formatKey;
    private _summarize;
    private _send;
    private valueToString;
}