import type { OpenAPIV3 } from 'openapi-types';
/**
 * Convert an OpenAPI document to ensure smooth parsing and generation thereafter.
 * Documents are transformed to JSON and compliant with OpenAPI version 3.
 * @param filePath - File content of the original spec.
 * @internal
 */
export declare function convertOpenApiSpec(filePath: string): Promise<OpenAPIV3.Document>;
/**
 * Parse a JSON or YAML file and return it as JSON.
 * @param filePath - Path to the file.
 * @returns JSON representation of the given file.
 * @internal
 */
export declare function parseFileAsJson(filePath: string): Promise<Record<string, any>>;
/**
 * Convert Swagger documents to OpenAPI documents.
 * If an OpenAPI document is passed it is not modified.
 * @param openApiDocument - OpenAPI version 2 (Swagger) or 3 document to be converted to version 3.
 * @returns A promise of an OpenAPI version 3 document.
 * @internal
 */
export declare function convertDocToOpenApiV3(openApiDocument: Record<string, any>): Promise<OpenAPIV3.Document>;