import { type ExportResult } from "@opentelemetry/core";
import { OTLPExporterError } from "@opentelemetry/otlp-exporter-base";
import type { ReadableSpan, SpanExporter } from "@opentelemetry/sdk-trace-base";
import type { FpxLogger } from "./logger.js";
import type { FetchFn } from "./types/index.js";
interface OTLPExporterConfig {
    url: string;
    headers?: Record<string, string>;
}
/**
 * @NOTE - We had to implement a custom SpanExporter because the OTLPTraceExporter
 *         was not working for us in Cloudflare Workers.
 *
 *         Specifically, the OTLPTraceExporter kept thinking that we were in the browser,
 *         _but only when we attached a `headers` object to the request._
 *
 *         The lack of browser APIs (XHR, sendBeacon) led to runtime errors.
 *
 *         Solution inspired by https://github.com/evanderkoogh/otel-cf-workers/blob/450435bc136d5b81aee655096aa4b8261f42d0c7/src/exporter.ts
 */
export declare class FPOTLPExporter implements SpanExporter {
    private headers;
    private url;
    private fetchFn;
    private logger;
    constructor(config: OTLPExporterConfig, fetchFn: FetchFn, logger: FpxLogger);
    export(items: Array<ReadableSpan>, resultCallback: (result: ExportResult) => void): void;
    private _export;
    send(items: Array<ReadableSpan>, onSuccess: () => void, onError: (error: OTLPExporterError) => void): void;
    shutdown(): Promise<void>;
}
export {};