import { StorageMiddleware } from "@worldbrain/storex/lib/types/middleware";
import { StorageRegistry } from "@worldbrain/storex";
export declare type CustomPkGenerator = () => string;
export declare class CustomAutoPkMiddleware implements StorageMiddleware {
    private _collections;
    private _pkGenerator;
    private _storageRegistry;
    constructor({ pkGenerator }: {
        pkGenerator: CustomPkGenerator;
    });
    setup({ storageRegistry, collections }: {
        storageRegistry: StorageRegistry;
        collections: string[];
    }): void;
    process({ next, operation }: {
        next: {
            process: ({ operation }: {
                operation: any;
            }) => any;
        };
        operation: any[];
    }): Promise<any>;
}