gRPC

definition:

gRPC is a high-performance Remote Procedure Call (RPC) framework that can run in various environments and efficiently connect services in and across data centers.

By default, gRPC employs Protocol Buffers to define message structures and RPC services.

example:

There are four types of gRPC service methods:

1. Unary RPC

The client sends a request and receives a response from the server. Similar with REST API style.

rpc SayHello(HelloRequest) returns (HelloResponse);

2. Server streaming RPC

The client sends a request and receives a stream of responses from the server. The client reads the responses until there are no responses.

rpc GetBooks(GetBooksRequest) returns (stream GetBooksResponse) {};

3. Client streaming RPC

The client sends a stream of requests and receives a response from the server. When the client finished sending the requests, the server handle the requests and returns a responses.

rpc AddBatchBook(stream AddBatchBookRequest) returns (AddBatchBookResponse) {};

4. Bidirectional streaming RPC

The client and the server send a sequence of messages using a read-write stream. The two streams operate independently in any order. For example, the server wait to receive all the client messages before returning the responses.

rpc BidiHello(stream HelloRequest) returns (stream HelloResponse);

This is the example of gRPC implementation in Go. This example covers the basic usages of gRPC.