import DataLoader from 'dataloader';
import { Currency } from '../../../shared/enums.js';
import { CoinMarketCapProvider } from '../../app-providers/coinmarketcap.js';
import { DBProvider } from '../../app-providers/db.provider.js';
import { IGetRateByCurrencyAndDateResult } from '../types.js';
export declare class CryptoExchangeProvider {
    private context;
    private dbProvider;
    private coinMarketCap;
    cache: {
        get: <T>(key: import("node-cache").Key) => T | undefined;
        set: {
            <T>(key: import("node-cache").Key, value: T, ttl: number | string): boolean;
            <T>(key: import("node-cache").Key, value: T): boolean;
        };
        delete: (keys: import("node-cache").Key | import("node-cache").Key[]) => number;
        clear: () => void;
    };
    fiatCurrency: Currency;
    constructor(context: GraphQLModules.Context, dbProvider: DBProvider, coinMarketCap: CoinMarketCapProvider);
    private getCryptoExchangeRatesFromDB;
    private addRates;
    private addCryptoRateLoader;
    private getCryptoCurrenciesBySymbol;
    private getCryptoCurrenciesBySymbolLoader;
    private getCryptoExchangeRatesFromAPI;
    getCryptoExchangeRateLoader: DataLoader<{
        cryptoCurrency: string;
        date: Date;
        against?: Currency;
    }, IGetRateByCurrencyAndDateResult, string>;
    clearCache(): void;
}