import { DEBUG, ERROR, INFO, LogLevels, WARN } from './logLevels';
export { DEBUG, ERROR, INFO, LogLevels, WARN };
export declare type Metadata = Record<any, any>;
export declare type PlatformMetadata = any;
export declare type Message = string;
export interface LogEventMetadata {
    [index: string]: any;
    platform: PlatformMetadata;
}
export interface LogEvent {
    level: LogLevels;
    message: Message;
    metadata: LogEventMetadata;
    timestamp: Date;
}
export interface Backend {
    log(event: LogEvent): Promise<void>;
}
export interface LoggerConfiguration {
    backends?: Backend[];
}
export declare function validateMetadata(metadata: Metadata): Record<any, any>;
export declare class Logger {
    private backends;
    private metadata;
    private static platformMetadata;
    constructor(opts?: LoggerConfiguration);
    info(message: Message, metadata?: Metadata): void;
    warn(message: Message, metadata?: Metadata): void;
    error(message: Message, metadata?: Metadata): void;
    debug(message: Message, metadata?: Metadata): void;
    setMetadata(metadata: Metadata): void;
    static setPlatformMetadata(metadata: Partial<PlatformMetadata>): void;
    private send;
    private combineMetadata;
}