一、定义服务
通过proto定义一个数学计算服务,其中包括两个服务方法(Add, Multipy)以及4个请求响应对象(AddRequest, AddReply, MultiplyRequest, MultiplyReply)。
// 文件名:mathservice.proto
syntax = "proto3";
option java_multiple_files = false;
option java_package = "MathServices";
option java_outer_classname = "MathServicesProto";
option objc_class_prefix = "MathServices";
package MathServices;
// 数学运算服务
service MathService
{
rpc Add (AddRequest) returns (AddReply) {}
rpc Multiply (MultiplyRequest) returns (MultiplyReply) {}
}
message AddRequest {
double First = 1;
double Second = 2;
}
message AddReply {
double Sum = 1;
}
message MultiplyRequest {
double First = 1;
double Second = 2;
}
message MultiplyReply {
double Result = 1;
}
二、将服务编译成存根(stub)
通过以下批处理命令generate_protos.bat
将服务定义生成多种语言和平台版本的客户端和服务端存根。
@rem 生成客户端和服务器端存根
setlocal
@rem 进入当前目录
cd /d %~dp0
set TOOLS_PATH=C:\Users\Freeman\.nuget\packages\Grpc.Tools\1.0.0\tools\windows_x86
%TOOLS_PATH%\protoc.exe ^
--proto_path protos ^
--cpp_out=Interfaces/cpp ^
--csharp_out=Interfaces/csharp ^
--java_out=Interfaces/java ^
--js_out=Interfaces/javascript ^
--grpc_out=Interfaces/csharp ^
--plugin=protoc-gen-grpc=%TOOLS_PATH%\grpc_csharp_plugin.exe ^
protos/mathservice.proto
endlocal
timeout 5
针对CSHARP语言,protoc.exe编译器生成了如下图几个类,其中左边4个类用于构造请求和响应对象,MathService类用于下一步构造服务和消费服务。
CSHARP STUBS
三、实现并运行服务
通过上一步的编译,自动生成了MathService类,下面通过该类构造并启动grpc服务。
通过继承基类实现服务接口
/// <summary>
/// 实现RPC服务端接口。
/// </summary>
public class MathServiceImpl : MathService.MathServiceBase
{
public override Task<AddReply> Add(AddRequest request, ServerCallContext context)
{
return Task.FromResult(new AddReply { Sum = request.First + request.Second });
}
public override Task<MultiplyReply> Multiply(MultiplyRequest request, ServerCallContext context)
{
return Task.FromResult(new MultiplyReply { Result = request.First * request.Second });
}
}
启动服务
const string ip = "0.0.0.0";
const int port = 50051;
Server server = new Server();
server.Ports.Add(new ServerPort(ip, port, ServerCredentials.Insecure));
server.Services.Add(MathService.BindService(new MathServiceImpl()));
server.Start();
server.Ports.ToList().ForEach(a => Console.WriteLine($"Server listening on port {a.Port}..."));
Console.ReadLine();
四、客户端调用服务
客户端通过创建一个Channel和一个服务客户端来使用服务。
var channel = new Channel($"{"127.0.0.1"}:{port}", SslCredentials.Insecure);
var client = new MathService.MathServiceClient(channel);
var random = new Random();
while (true)
{
var first = random.NextDouble();
var second = random.NextDouble();
var reply = client.Add(new AddRequest { First = first, Second = second });
Console.WriteLine($"RPC call Add service: {first:F4} + {second:F4} = {reply.Sum:F4}");
Thread.Sleep(500);
}
RPC调用
五、使用SSL实现加密通讯
grpc默认实现了基于证书的SSL加密通讯,使用中需要注意以下事项。
-
通过以下样例脚本生成通讯中所需要的服务端和客户端证书,其中需要特别注意的是,Generate server signing request:中的CN=KEKYK字段如果是本机测试,请一定使用本机名称,如果是真实环境请使用域名,因为客户端必须通过机器名(本地测试)或域名访问该服务。如果此处CN字段不使用机器名或域名,将导致以下错误:
CN字段不使用主机名或域名时产生的错误 -
生成服务端和客户端证书脚本generate_ssl.bat
@echo off
set OPENSSL_CONF=c:\OpenSSL-Win64\bin\openssl.cfg
echo Generate CA key:
openssl genrsa -passout pass:1111 -des3 -out ca.key 4096
echo Generate CA certificate:
openssl req -passin pass:1111 -new -x509 -days 365 -key ca.key -out ca.crt -subj "/C=US/ST=CA/L=Cupertino/O=YourCompany/OU=YourApp/CN=MyRootCA"
echo Generate server key:
openssl genrsa -passout pass:1111 -des3 -out server.key 4096
echo Generate server signing request:
openssl req -passin pass:1111 -new -key server.key -out server.csr -subj "/C=US/ST=CA/L=Cupertino/O=YourCompany/OU=YourApp/CN=kekyk"
echo Self-sign server certificate:
openssl x509 -req -passin pass:1111 -days 365 -in server.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out server.crt
echo Remove passphrase from server key:
openssl rsa -passin pass:1111 -in server.key -out server.key
echo Generate client key
openssl genrsa -passout pass:1111 -des3 -out client.key 4096
echo Generate client signing request:
openssl req -passin pass:1111 -new -key client.key -out client.csr -subj "/C=US/ST=CA/L=Cupertino/O=YourCompany/OU=YourApp/CN=client"
echo Self-sign client certificate:
openssl x509 -passin pass:1111 -req -days 365 -in client.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out client.crt
echo Remove passphrase from client key:
openssl rsa -passin pass:1111 -in client.key -out client.key
pause
- 基于SSL的服务端启动如下,创建服务的时候请使用主机名(开发环境)或域名(生产环境),不要使用IP地址。
public static void RpcServerSsl()
{
var cacert = File.ReadAllText(CombinePath("ca.crt"));
var servercert = File.ReadAllText(CombinePath("server.crt"));
var serverkey = File.ReadAllText(CombinePath("server.key"));
var keypair = new KeyCertificatePair(servercert, serverkey);
var sslCredentials = new SslServerCredentials(new List<KeyCertificatePair>() { keypair }, cacert, false);
var server = new Server
{
Services = { MathService.BindService(new MathServiceImpl()) },
Ports = { new ServerPort("KEKYK", sslPort, sslCredentials) }
};
server.Start();
server.Ports.ToList().ForEach(a => Console.WriteLine($"Server (SSL) listening on port {a.Port}..."));
Console.ReadLine();
}
- 基于SSL的客户端使用如下,注意测试环境中使用主机名,生产环境中使用域名来,不要使用任何形式的IP地址。
public static void RpcClientSsl()
{
var cacert = File.ReadAllText(CombinePath("ca.crt"));
var clientcert = File.ReadAllText(CombinePath("client.crt"));
var clientkey = File.ReadAllText(CombinePath("client.key"));
var ssl = new SslCredentials(cacert, new KeyCertificatePair(clientcert, clientkey));
var channel = new Channel("KEKYK", sslPort, ssl);
var client = new MathService.MathServiceClient(channel);
var random = new Random();
while (true)
{
var first = random.NextDouble();
var second = random.NextDouble();
var reply = client.AddAsync(new AddRequest { First = first, Second = second }, new CallOptions()).ResponseAsync.Result;
Console.WriteLine($"RPC call Add service: {first:F4} + {second:F4} = {reply.Sum:F4}");
Thread.Sleep(1000);
}
}