import * as grpc from "grpc";
import { Metadata } from "grpc";
import { Observable, Subject, Observer } from 'rxjs';
import './observable.iterator';
export declare type ObservableGrpcCall<Client extends grpc.Client, Property extends keyof Client, Unary = ReturnType<((...args: any) => any) & Client[Property]>, ClientStream = ReturnType<((...args: any) => any) & Client[Property]>, ServerStream = ReturnType<((...args: any) => any) & Client[Property]>, Duplex = ReturnType<((...args: any) => any) & Client[Property]>> = Duplex extends grpc.ClientDuplexStream<infer DuplexInput, infer DuplexOutput> ? (subjectStream: Subject<DuplexInput>, metadata?: Parameters<(() => void) & Client[Property]>[0], grpcOptions?: Parameters<(() => void) & Client[Property]>[1]) => Observable<DuplexOutput> : ClientStream extends grpc.ClientWritableStream<infer ClientStreamOutput> ? (subjectStream: Subject<ClientStreamOutput>, metadata?: Parameters<(() => void) & Client[Property]>[0], grpcOptions?: Parameters<(() => void) & Client[Property]>[1]) => Observable<ClientStreamOutput> : ServerStream extends grpc.ClientReadableStream<infer ServerStreamOutput> ? (request: (Parameters<(() => void) & Client[Property]>[0]), metadata?: Parameters<(() => void) & Client[Property]>[1], grpcOptions?: Parameters<(() => void) & Client[Property]>[2]) => Observable<ServerStreamOutput> : Unary extends grpc.ClientUnaryCall ? (request: (Parameters<(() => void) & Client[Property]>[0]), metadata?: Parameters<(() => void) & Client[Property]>[1], grpcOptions?: Parameters<(() => void) & Client[Property]>[2]) => Observable<Parameters<Parameters<((...args: any[]) => void) & Client[Property]>[3]>[1]> : Client[Property];
declare type ObservableGrpc<Client extends grpc.Client, ClientMethodNames extends keyof Client = keyof Client> = {
    [P in ClientMethodNames]: ObservableGrpcCall<Client, P>;
};
/**
 * GrpcRequest
 */
export declare class GrpcRequest<Client extends grpc.Client> {
    protected readonly _client: Client & Record<string | symbol | number, any>;
    protected readonly _metadata: Metadata;
    protected readonly _options?: grpc.CallOptions | undefined;
    protected constructor(_client: Client & Record<string | symbol | number, any>, _metadata?: Metadata, _options?: grpc.CallOptions | undefined);
    static create<Client extends grpc.Client>(client: Client, metadata?: Metadata, options?: grpc.CallOptions): GrpcRequest<Client> & ObservableGrpc<Client, keyof Client>;
    get client(): Client & Record<string | number | symbol, any>;
    withMetadata(metadata: Record<string, any>): this;
    protected callReactiveGrpcMethod(methodName: string | number | symbol, ...args: any[]): Observable<unknown>;
    /**
     * Unary call handler
     * @param observer
     */
    protected unaryHandler<T>(observer: Observer<T>): (err: Error, response: T) => void;
    /**
     * get the appropriate grpc call arguments
     * @param args
     */
    protected gRPCCallArguments(...args: any[]): any[];
}
export {};