/// <reference types="node" />
import { AxiosRequestConfig, AxiosResponse } from 'axios';
import { Middleware } from 'koa-compose';
import { Span } from 'opentracing';
import { CacheLayer } from '../caches/CacheLayer';
import { MetricsAccumulator } from '../metrics/MetricsAccumulator';
import { IOContext } from '../service/worker/runtime/typings';
import { SpanReferenceTypes } from '../tracing';
import { IUserLandTracer } from '../tracing/UserLandTracer';
import { Cached, CacheType } from './middlewares/cache';
export type InflightKeyGenerator = (x: RequestConfig) => string;
interface RequestTracingUserConfig {
    rootSpan?: Span;
    referenceType?: SpanReferenceTypes;
    requestSpanNameSuffix?: string;
}
export interface RequestTracingConfig {
    tracing?: RequestTracingUserConfig;
}
export interface RequestConfig extends AxiosRequestConfig, RequestTracingConfig {
    retries?: number;
    exponentialTimeoutCoefficient?: number;
    initialBackoffDelay?: number;
    exponentialBackoffCoefficient?: number;
    retryCount?: number;
    /**
     * Identifies the type of request for metrification purposes. Should vary with client method.
     */
    metric?: string;
    /**
     * In verbose mode, a counter will be incremented for each request made with the same `metric` label.
     */
    count?: number;
    /**
     * In verbose mode, a label will be created with a counter for each request made with the same `metric` label.
     */
    label?: string;
    /**
     * Outputs verbose logs to console for this request.
     */
    verbose?: boolean;
    production?: boolean;
    cacheable?: CacheType;
    memoizeable?: boolean;
    inflightKey?: InflightKeyGenerator;
    forceMaxAge?: number;
    responseEncoding?: BufferEncoding | string;
    nullIfNotFound?: boolean;
    ignoreRecorder?: boolean;
}
export interface CacheHit {
    disk?: 0 | 1;
    memory?: 0 | 1;
    revalidated?: 0 | 1;
    router?: 0 | 1;
}
export interface MiddlewaresTracingContext extends Omit<RequestTracingUserConfig, 'rootSpan'> {
    tracer: IUserLandTracer;
    logger: IOContext['logger'];
    rootSpan?: Span;
    isSampled: boolean;
}
export interface MiddlewareContext {
    config: RequestConfig;
    tracing?: MiddlewaresTracingContext;
    response?: AxiosResponse;
    cacheHit?: CacheHit;
    inflightHit?: boolean;
    memoizedHit?: boolean;
}
export type CacheStorage = CacheLayer<string, Cached>;
export interface InstanceOptions {
    authType?: AuthType;
    timeout?: number;
    memoryCache?: CacheLayer<string, Cached>;
    diskCache?: CacheLayer<string, Cached>;
    asyncSetCache?: boolean;
    /**
     * Enables memoization, ephemeral within each request, for all requests of this client.
     * Useful for services that makes recursive requests, like graphql resolvers, which
     * might fetch the same endpoint more than once.
     * If that's not the case for your service, disabling it might improve the CPU and
     * memory usage.
     *
     * Default value: true
     */
    memoizable?: boolean;
    baseURL?: string;
    retries?: number;
    exponentialTimeoutCoefficient?: number;
    initialBackoffDelay?: number;
    exponentialBackoffCoefficient?: number;
    metrics?: MetricsAccumulator;
    /**
     * Maximum number of concurrent requests
     *
     * @type {number}
     * @memberof InstanceOptions
     */
    concurrency?: number;
    /**
     * Default headers to be sent with every request
     *
     * @type {Record<string, string>}
     * @memberof InstanceOptions
     */
    headers?: Record<string, string>;
    /**
     * Default query string parameters to be sent with every request
     *
     * @type {Record<string, string>}
     * @memberof InstanceOptions
     */
    params?: Record<string, string>;
    middlewares?: Array<Middleware<MiddlewareContext>>;
    verbose?: boolean;
    name?: string;
    serverTimings?: Record<string, string>;
    httpsAgent?: AxiosRequestConfig['httpsAgent'];
    cacheableType?: CacheType;
}
export interface IOResponse<T> {
    data: T;
    headers: Record<string, string>;
    status: number;
}
export declare enum AuthType {
    basic = "Basic",
    bearer = "Bearer",
    /**
     * Supported for legacy reasons - this is not spec compliant!
     */
    token = "token"
}
export {};