import { Observable } from 'rxjs';
import { ExecutionContext } from './execution-context.interface';
/**
 * Interface providing access to the response stream.
 *
 * @see [Interceptors](https://docs.nestjs.com/interceptors)
 *
 * @publicApi
 */
export interface CallHandler<T = any> {
    /**
     * Returns an `Observable` representing the response stream from the route
     * handler.
     */
    handle(): Observable<T>;
}
/**
 * Interface describing implementation of an interceptor.
 *
 * @see [Interceptors](https://docs.nestjs.com/interceptors)
 *
 * @publicApi
 */
export interface NestInterceptor<T = any, R = any> {
    /**
     * Method to implement a custom interceptor.
     *
     * @param context an `ExecutionContext` object providing methods to access the
     * route handler and class about to be invoked.
     * @param next a reference to the `CallHandler`, which provides access to an
     * `Observable` representing the response stream from the route handler.
     */
    intercept(context: ExecutionContext, next: CallHandler<T>): Observable<R> | Promise<Observable<R>>;
}