import type { IBrokerMessageRoutingOptions, IMessageBrokerService } from '../../types';
export declare class GooglePubSubService implements IMessageBrokerService {
    private config;
    private pubSubClient;
    constructor(config: {
        projectId?: string;
        credentials?: {
            client_email: string;
            private_key: string;
            project_id?: string;
        };
        config?: {
            project_id?: string;
            client_email?: string;
            private_key?: string;
        };
    });
    connect(): Promise<void>;
    publish(topic: string, message: object, options?: IBrokerMessageRoutingOptions): Promise<void>;
    subscribe(topicName: string, callback: (message: object) => Promise<void>, options?: IBrokerMessageRoutingOptions): Promise<void>;
    disconnect(): Promise<void>;
}