import { ApolloCache } from 'apollo-cache';
import { CachePersistor } from '..';
export declare type LogLevel = 'log' | 'warn' | 'error';
export declare type LogLine = [LogLevel, any[]];
export declare type TriggerUninstallFunction = () => void;
export declare type TriggerFunction = (persist: () => void) => TriggerUninstallFunction;
export declare type PersistedData<T> = T | string | null;
export interface PersistentStorage<T> {
    getItem: (key: string) => Promise<T> | T;
    setItem: (key: string, data: T) => Promise<void> | void;
    removeItem: (key: string) => Promise<void> | void;
}
export declare type OnEncryptionError<T> = (error: Error, persistor: CachePersistor<T>) => void;
export interface EncryptOptions<T> {
    onError?: OnEncryptionError<T>;
    secretKey: string;
}
export interface ApolloPersistOptions<TSerialized> {
    cache: ApolloCache<TSerialized>;
    storage: PersistentStorage<PersistedData<TSerialized>>;
    trigger?: 'write' | 'background' | TriggerFunction | false;
    debounce?: number;
    key?: string;
    serialize?: boolean;
    maxSize?: number | false;
    debug?: boolean;
    encrypt?: EncryptOptions<TSerialized>;
}