Merge pull request #26 from lambdaliu/add_quick_start

add quick start example

examples/quickstart/Makefile

@@ -0,0 +1,27 @@
+BIT = $(shell getconf LONG_BIT)
+
+POLARIS_CPP = ../..
+POLARIS_INCL = $(POLARIS_CPP)/include
+POLARIS_LIB_DIR = $(POLARIS_CPP)/build$(BIT)/lib
+POLARIS_LIB = $(POLARIS_LIB_DIR)/libpolaris_api.a
+PROTOBUF_LIB = $(POLARIS_CPP)/third_party/protobuf/build$(BIT)/libprotobuf.a
+
+CXX = g++
+CXXFLAGS += -g -Wall -Wno-write-strings -Werror -std=c++11
+
+SRC = $(wildcard *.cpp)
+OBJECTS = $(SRC:%.cpp=%)
+
+all: $(OBJECTS)
+
+%: %.cpp $(POLARIS_LIB)
+	@echo -e Building $< ...
+	$(CXX) $(CXXFLAGS) -I$(POLARIS_INCL) $< $(POLARIS_LIB) $(PROTOBUF_LIB) -pthread -lz -o $@
+
+$(POLARIS_LIB):
+	@echo build polaris-cpp lib
+	make -C ${POLARIS_CPP}
+
+clean:
+	@echo -e Clean $(OBJECTS)
+	@-rm -rf $(OBJECTS)

examples/quickstart/README-zh.md

@@ -0,0 +1,53 @@
+# 快速开始样例
+
+## 样例说明
+
+样例演示如何使用 polaris-cpp 完成被调端以及主调端应用接入polaris，并完成服务调用流程。
+
+consumer: 接收用户tcp请求，通过polaris发现provider服务，并将请求转发给provider处理
+provider：启动服务监听端口，并自身注册到北极星，且开启健康检查
+
+## 编译
+
+```bash
+make clean
+make
+```
+
+编译完成后，会在当前目录生成两个二进制文件，consumer和provider
+
+## 运行
+
+在当前目录下创建配置文件 polaris.yaml，配置文件中配置 Polaris Server 地址。
+
+```yaml
+global:
+  serverConnector:
+    addresses:
+    - 127.0.0.1:8081
+```
+
+执行样例
+
+需要在控制台先创建被调服务 Test/quickstart.echo.service
+
+启动被调方：
+
+```bash
+# 监听地址端口 127.0.0.1:9091  注册到服务 Test/quickstart.echo.service 服务token为xxx
+./provider Test quickstart.echo.service xxx 127.0.0.1 9092
+```
+
+启动主调方：
+
+```bash
+# 监听地址端口 127.0.0.1:9093  转发请求到被调服务 Test/quickstart.echo.service
+./consumer 127.0.0.1 9093 Test quickstart.echo.service
+```
+
+发送测试请求：
+
+```bash
+# 向consumer监听端口发送hello
+echo hello | nc 127.0.0.1 9093
+```

examples/quickstart/consumer.cpp

@@ -0,0 +1,258 @@
+//  Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.
+//
+//  Licensed under the BSD 3-Clause License (the "License"); you may not use this file
+//  except in compliance with the License. You may obtain a copy of the License at
+//
+//  https://opensource.org/licenses/BSD-3-Clause
+//
+//  Unless required by applicable law or agreed to in writing, software distributed
+//  under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+//  CONDITIONS OF ANY KIND, either express or implied. See the License for the specific
+//  language governing permissions and limitations under the License.
+//
+
+#include <arpa/inet.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include <chrono>
+#include <future>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <thread>
+
+#include "polaris/consumer.h"
+
+class ConsumerServer {
+public:
+  ConsumerServer(const std::string& host, int port, const polaris::ServiceKey& provider_service);
+
+  ~ConsumerServer();
+
+  int Start();
+
+  void Stop();
+
+private:
+  std::string Proccess(const std::string& message);
+
+  int Send(const std::string& host, int port, const std::string& request, std::string& response);
+
+private:
+  std::string host_;
+  int port_;
+  polaris::ServiceKey provider_service_;
+
+  std::atomic<bool> stop_;
+  std::unique_ptr<std::thread> accept_thread_;
+
+  std::unique_ptr<polaris::ConsumerApi> consumer_;
+};
+
+bool signal_received = false;
+void SignalHandler(int signum) {
+  std::cout << "Interrupt signal (" << signum << ") received." << std::endl;
+  signal_received = true;
+}
+
+int main(int argc, char** argv) {
+  if (argc < 5) {
+    std::cout << "usage: " << argv[0] << " host port service_namespace service_name" << std::endl;
+    return -1;
+  }
+  // register signal handler
+  signal(SIGINT, SignalHandler);
+
+  polaris::ServiceKey service_key = {argv[3], argv[4]};
+  ConsumerServer server(argv[1], atoi(argv[2]), service_key);
+
+  // 启动服务
+  if (server.Start() != 0) {
+    return -2;
+  }
+
+  // 循环等待退出信号
+  while (!signal_received) {
+    sleep(1);
+  }
+
+  // 反注册完成以后再停止服务
+  server.Stop();
+
+  return 0;
+}
+
+ConsumerServer::ConsumerServer(const std::string& host, int port,
+                               const polaris::ServiceKey& provider_service)
+    : host_(host), port_(port), provider_service_(provider_service), stop_(false) {
+  consumer_ = std::unique_ptr<polaris::ConsumerApi>(polaris::ConsumerApi::CreateWithDefaultFile());
+}
+
+ConsumerServer::~ConsumerServer() {}
+
+int ConsumerServer::Start() {
+  auto sock_listener = socket(AF_INET, SOCK_STREAM, 0);
+  if (sock_listener < 0) {
+    std::cerr << "create socket with error: " << errno << std::endl;
+    return -1;
+  }
+
+  // address info to bind socket
+  sockaddr_in server_addr;
+  server_addr.sin_family = AF_INET;
+  inet_pton(AF_INET, host_.c_str(), &server_addr.sin_addr);
+  server_addr.sin_port = htons(port_);
+
+  // bind socket
+  if (bind(sock_listener, (sockaddr*)&server_addr, sizeof(server_addr)) < 0) {
+    std::cerr << "bind to " << host_ << ":" << port_ << " failed with error: " << errno
+              << std::endl;
+    close(sock_listener);
+    return -2;
+  }
+
+  // start listening
+  if (listen(sock_listener, SOMAXCONN) < 0) {
+    std::cerr << "listen to " << host_ << ":" << port_ << " failed with error: " << errno
+              << std::endl;
+    close(sock_listener);
+    return -3;
+  }
+  std::cout << "listen to " << host_ << ":" << port_ << " success" << std::endl;
+
+  // create accept thread
+  accept_thread_ = std::unique_ptr<std::thread>(new std::thread([=] {
+    while (!stop_) {
+      fd_set set;
+      FD_ZERO(&set);
+      FD_SET(sock_listener, &set);
+      struct timeval timeout;
+      timeout.tv_sec  = 2;
+      timeout.tv_usec = 0;
+      int ret         = select(sock_listener + 1, &set, NULL, NULL, &timeout);
+      if (ret <= 0) {
+        continue;
+      }
+      sockaddr_in client_addr;
+      socklen_t client_addr_size = sizeof(client_addr);
+      int sock_client;
+      if ((sock_client = accept(sock_listener, (sockaddr*)&client_addr, &client_addr_size)) < 0) {
+        std::cerr << "accept connection failed with error:" << errno << std::endl;
+        continue;
+      }
+
+      // 处理客户端连接
+      std::async(std::launch::async, [=] {
+        char buffer[1024];
+        auto bytes = recv(sock_client, buffer, sizeof(buffer), 0);
+        if (bytes <= 0) {
+          std::cerr << "received message failed: " << errno << std::endl;
+          close(sock_client);
+          return;
+        }
+        std::string response = Proccess(buffer);
+        bytes                = send(sock_client, response.data(), response.size(), 0);
+        close(sock_client);
+
+        if (bytes < 0) {
+          std::cerr << "send response failed: " << errno << std::endl;
+        }
+      });
+    }
+    close(sock_listener);
+  }));
+
+  return 0;
+}
+
+std::string ConsumerServer::Proccess(const std::string& message) {
+  // 获取provider服务实例
+  polaris::GetOneInstanceRequest instance_requst(provider_service_);
+  polaris::Instance instance;
+  auto ret_code = consumer_->GetOneInstance(instance_requst, instance);
+  if (ret_code != polaris::kReturnOk) {
+    std::cout << "get one instance for service with error: "
+              << polaris::ReturnCodeToMsg(ret_code).c_str() << std::endl;
+  }
+
+  // 调用业务
+  std::string response;
+  auto begin_time = std::chrono::steady_clock::now();
+  int send_ret    = Send(instance.GetHost(), instance.GetPort(), message, response);
+  auto end_time   = std::chrono::steady_clock::now();
+
+  // 上报调用结果
+  polaris::ServiceCallResult result;
+  result.SetServiceNamespace(provider_service_.namespace_);
+  result.SetServiceName(provider_service_.name_);
+  result.SetInstanceId(instance.GetId());
+  result.SetDelay(
+      std::chrono::duration_cast<std::chrono::milliseconds>(end_time - begin_time).count());
+  result.SetRetCode(send_ret);
+  result.SetRetStatus(send_ret >= 0 ? polaris::kCallRetOk : polaris::kCallRetError);
+  if ((ret_code = consumer_->UpdateServiceCallResult(result)) != polaris::kReturnOk) {
+    std::cout << "update call result for instance with error:"
+              << " msg:" << polaris::ReturnCodeToMsg(ret_code).c_str() << std::endl;
+  }
+
+  if (send_ret) {
+    response =
+        "send msg to " + instance.GetHost() + ":" + std::to_string(instance.GetPort()) + " failed";
+  }
+  std::cout << response << std::endl;
+  return response;
+}
+
+int ConsumerServer::Send(const std::string& host, int port, const std::string& request,
+                         std::string& response) {
+  // create a socket
+  int sock_fd = socket(AF_INET, SOCK_STREAM, 0);
+  if (sock_fd < 0) {
+    std::cout << "create socket failed: " << errno << std::endl;
+    return -1;
+  }
+
+  sockaddr_in server_addr;
+  server_addr.sin_family = AF_INET;
+  inet_pton(AF_INET, host.c_str(), &server_addr.sin_addr);
+  server_addr.sin_port = htons(port);
+
+  if (connect(sock_fd, (sockaddr*)&server_addr, sizeof(server_addr)) < 0) {
+    std::cerr << "connection establish failed: " << errno << std::endl;
+    close(sock_fd);
+    return -2;
+  }
+
+  // send the message
+  int bytes_send = send(sock_fd, request.data(), request.length(), 0);
+  if (bytes_send < 0) {
+    std::cerr << "send message failed: " << errno << std::endl;
+    close(sock_fd);
+    return -3;
+  }
+
+  char buffer[4096];
+  int bytes_recv = recv(sock_fd, &buffer, sizeof(buffer), 0);
+  if (bytes_recv <= 0) {
+    std::cerr << "receive message failed: " << errno << std::endl;
+    close(sock_fd);
+    return -4;
+  }
+
+  close(sock_fd);
+  response = std::string(buffer);
+  return 0;
+}
+
+void ConsumerServer::Stop() {
+  stop_ = true;
+  if (accept_thread_) {
+    accept_thread_->join();
+  }
+}