IBM/node-celery-ts

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import { TaskMessage } from "./messages";

/**
 * MessageBroker encapsulates transactions with message brokering middleware.
 */
export interface MessageBroker {
    /**
     * If possible, quickly disconnects from the broker. Call only once.
     *
     * @return A Promise that resolves when the broker is disconnected.
     */
    disconnect(): Promise<void>;

    /**
     * Gently disconnects from the broker. Should only be called once.
     *
     * @returns A Promise that resolves when the broker is disconnected.
     */
    end(): Promise<void>;

    /**
     * Publishes a message onto the broker.
     *
     * @param message The message to be published. Used to infer transport
     *                options.
     * @returns A Promise that resolves to the response of the broker after the
     *          operation is completed.
     */
    publish(message: TaskMessage): Promise<string>;
}