io.vertx.grpc.client

Interface GrpcClient

public interface GrpcClient

A gRPC client for Vert.x Unlike traditional gRPC clients, this client does not rely on a generated RPC interface to interact with the service. Instead, you can interact with the service with a request/response interfaces and gRPC messages, very much like a traditional client. The client exposes 2 levels of API

• a Protobuf message API: GrpcClientRequest/GrpcClientResponse with Protobuf messages to call any gRPC service in a generic way
• a gRPC message request(SocketAddress, MethodDescriptor): GrpcClientRequest/GrpcClientRequest with gRPC messages to call a given method of a gRPC service

Method Summary

Modifier and Type	Method and Description
default <Req,Resp,T> Future<T>	call(SocketAddress server, io.grpc.MethodDescriptor<Req,Resp> service, Handler<GrpcClientRequest<Req,Resp>> requestHandler, java.util.function.Function<GrpcClientResponse<Req,Resp>,Future<T>> resultFn) Call the service gRPC service hosted by server.
static GrpcClient	client(Vertx vertx) Create a new client
static GrpcClient	client(Vertx vertx, HttpClientOptions options) Create a new client
Future<Void>	close() Close this client.
Future<GrpcClientRequest<Buffer,Buffer>>	request(SocketAddress server) Connect to the remote server and create a request for any hosted gRPC service.
<Req,Resp> Future<GrpcClientRequest<Req,Resp>>	request(SocketAddress server, io.grpc.MethodDescriptor<Req,Resp> service) Connect to the remote server and create a request for given method of a hosted gRPC service.

Method Detail

client

static GrpcClient client(Vertx vertx)

Create a new client

Parameters:

vertx - the vertx instance

Returns:

the created client

client

static GrpcClient client(Vertx vertx,
                         HttpClientOptions options)

Create a new client

Parameters:

vertx - the vertx instance

options - the client options

Returns:

the created client

request

Future<GrpcClientRequest<Buffer,Buffer>> request(SocketAddress server)

Connect to the remote server and create a request for any hosted gRPC service.

Parameters:

server - the server hosting the service

Returns:

a future request

request

<Req,Resp> Future<GrpcClientRequest<Req,Resp>> request(SocketAddress server,
                                                       io.grpc.MethodDescriptor<Req,Resp> service)

Connect to the remote server and create a request for given method of a hosted gRPC service.

Parameters:

server - the server hosting the service

service - the service to be called

Returns:

a future request

call

default <Req,Resp,T> Future<T> call(SocketAddress server,
                                    io.grpc.MethodDescriptor<Req,Resp> service,
                                    Handler<GrpcClientRequest<Req,Resp>> requestHandler,
                                    java.util.function.Function<GrpcClientResponse<Req,Resp>,Future<T>> resultFn)

Call the service gRPC service hosted by server.

The requestHandler is called to send the request, e.g. req -> req.send(item)

The responseFunction extracts the result, e.g. resp -> resp.last()

It can be used in various ways:

• Future<Resp> fut = client.call(..., req -> req.send(item), resp -> resp.last());
• Future<Void> fut = client.call(..., req -> req.send(stream), resp -> resp.pipeTo(anotherService));
• Future<List<Resp>> fut = client.call(..., req -> req.send(stream), resp -> resp.collecting(Collectors.toList()));

Parameters:

server - the server hosting the service

service - the service to call

requestHandler - the handler called to send the request

resultFn - the function applied to extract the result.

Returns:

a future of the result

close

Future<Void> close()

Close this client.