## 5) 獲取Route信息 ### 5.1 proto協議定義 ? 獲取Route信息，根據之前的架構圖，可以看出來應該是Agent來獲取，這里我們并沒有實現Agent，所以用一個其他簡單的客戶端來完成單元測試。但是無論用什么，總需要一個傳遞數據，需要一定的消息協議，lars-dns也需要設置不同纖細的分發消息路由機制，所以我們需要先定義一些proto協議。 ? 在`Lars/base`下創建`proto/`文件夾. > Lars/base/proto/lars.proto ```protobuf syntax = "proto3"; package lars; /* Lars系統的消息ID */ enum MessageId { ID_UNKNOW = 0; //proto3 enum第一個屬性必須是0，用來占位 ID_GetRouteRequest = 1; //向DNS請求Route對應的關系的消息ID ID_GetRouteResponse = 2; //DNS回復的Route信息的消息ID } //一個管理的主機的信息 message HostInfo { int32 ip = 1; int32 port = 2; } //請求lars-dns route信息的消息內容 message GetRouteRequest { int32 modid = 1; int32 cmdid = 2; } //lars-dns 回復的route信息消息內容 message GetRouteResponse { int32 modid = 1; int32 cmdid = 2; repeated HostInfo host = 3; } ``` ? 然后我們將proto文件編譯成對應的C++文件, 我們還是提供一個腳本 > Lars/base/proto/build.sh ```bash #!/bin/bash # proto編譯 protoc --cpp_out=. ./*.proto # 將全部的cc 文件 變成 cpp文件 oldsuffix="cc" newsuffix="cpp" dir=$(eval pwd) for file in $(ls $dir | grep .${oldsuffix}) do name=$(ls ${file} | cut -d. -f1,2) mv $file ${name}.${newsuffix} done echo "build proto file successd!" ``` ? 因為protoc會自動生成cc后綴的文件，為了方便我們Makefile的編譯，所以將cc文件改成cpp的。 ### 5.2 proto編譯環境集成 ? 現在我們將`lars-dns`的Makefile加入針對proto文件的編譯 > Lars/lars_dns/Makefile ```makefile TARGET= bin/lars_dns CXX=g++ CFLAGS=-g -O2 -Wall -Wno-deprecated BASE=../base BASE_H=$(BASE)/include PROTO = $(BASE)/proto PROTO_H = $(BASE)/proto LARS_REACTOR=../lars_reactor LARS_REACTOR_H =$(LARS_REACTOR)/include LARS_REACTOR_LIB=$(LARS_REACTOR)/lib -llreactor MYSQL=$(BASE)/mysql-connector-c MYSQL_H=$(MYSQL)/include MYSQL_LIB=$(MYSQL)/lib/libmysqlclient.a OTHER_LIB = -lpthread -ldl -lprotobuf SRC= ./src INC= -I./include -I$(BASE_H) -I$(LARS_REACTOR_H) -I$(MYSQL_H) -I$(PROTO_H) LIB= $(MYSQL_LIB) -L$(LARS_REACTOR_LIB) $(OTHER_LIB) OBJS = $(addsuffix .o, $(basename $(wildcard $(SRC)/*.cpp))) OBJS += $(PROTO)/lars.pb.o $(TARGET): $(OBJS) mkdir -p bin $(CXX) $(CFLAGS) -o $(TARGET) $(OBJS) $(INC) $(LIB) %.o: %.cpp $(CXX) $(CFLAGS) -c -o $@ $< $(INC) .PHONY: clean clean: -rm -f src/*.o $(TARGET) ``` ? 添加了兩個部分一個`OBJS`增添一個`lars.pb.o`的依賴，然后再`OTHER_LIB`增加`-lprotobuf`動態庫的連接。 ### 5.3 實現Route獲取 ? 接下來我們來實現針對`ID_GetRouteRequest`消息指令的業務處理. > lars_dns/src/dns_service.cpp ```c #include "lars_reactor.h" #include "dns_route.h" #include "lars.pb.h" void get_route(const char *data, uint32_t len, int msgid, net_connection *net_conn, void *user_data) { //1. 解析proto文件 lars::GetRouteRequest req; req.ParseFromArray(data, len); //2. 得到modid 和 cmdid int modid, cmdid; modid = req.modid(); cmdid = req.cmdid(); //3. 根據modid/cmdid 獲取 host信息 host_set hosts = Route::instance()->get_hosts(modid, cmdid); //4. 將數據打包成protobuf lars::GetRouteResponse rsp; rsp.set_modid(modid); rsp.set_cmdid(cmdid); for (host_set_it it = hosts.begin(); it != hosts.end(); it ++) { uint64_t ip_port = *it; lars::HostInfo host; host.set_ip((uint32_t)(ip_port >> 32)); host.set_port((int)(ip_port)); rsp.add_host()->CopyFrom(host); } //5. 發送給客戶端 std::string responseString; rsp.SerializeToString(&responseString); net_conn->send_message(responseString.c_str(), responseString.size(), lars::ID_GetRouteResponse) ; } int main(int argc, char **argv) { event_loop loop; //加載配置文件 config_file::setPath("conf/lars_dns.conf"); std::string ip = config_file::instance()->GetString("reactor", "ip", "0.0.0.0"); short port = config_file::instance()->GetNumber("reactor", "port", 7778); //創建tcp服務器 tcp_server *server = new tcp_server(&loop, ip.c_str(), port); //注冊路由業務 server->add_msg_router(lars::ID_GetRouteRequest, get_route); //開始事件監聽 printf("lars dns service ....\n"); loop.event_process(); return 0; } ``` ? 需要給`Route`類，實現一個get_host()方法，來針對modid/cmdid取出對應的value > lars_dns/src/dns_route.cpp ```c //獲取modid/cmdid對應的host信息 host_set Route::get_hosts(int modid, int cmdid) { host_set hosts; //組裝key uint64_t key = ((uint64_t)modid << 32) + cmdid; pthread_rwlock_rdlock(&_map_lock); route_map_it it = _data_pointer->find(key); if (it != _data_pointer->end()) { //找到對應的ip + port對 hosts = it->second; } pthread_rwlock_unlock(&_map_lock); return hosts; } ``` ### 5.3 lars_dns獲取Route信息測試-V0.2 ? 下面我們寫一個客戶端檢查測試一下該功能. > lars_dns/test/lars_dns_test1.cpp ```c #include <string.h> #include <unistd.h> #include <string> #include "lars_reactor.h" #include "lars.pb.h" //命令行參數 struct Option { Option():ip(NULL),port(0) {} char *ip; short port; }; Option option; void Usage() { printf("Usage: ./lars_dns_test -h ip -p port\n"); } //解析命令行 void parse_option(int argc, char **argv) { for (int i = 0; i < argc; i++) { if (strcmp(argv[i], "-h") == 0) { option.ip = argv[i + 1]; } else if (strcmp(argv[i], "-p") == 0) { option.port = atoi(argv[i + 1]); } } if ( !option.ip || !option.port ) { Usage(); exit(1); } } //typedef void (*conn_callback)(net_connection *conn, void *args); void on_connection(net_connection *conn, void *args) { //發送Route信息請求 lars::GetRouteRequest req; req.set_modid(1); req.set_cmdid(2); std::string requestString; req.SerializeToString(&requestString); conn->send_message(requestString.c_str(), requestString.size(), lars::ID_GetRouteRequest); } void deal_get_route(const char *data, uint32_t len, int msgid, net_connection *net_conn, void *user_data) { //解包得到數據 lars::GetRouteResponse rsp; rsp.ParseFromArray(data, len); //打印數據 printf("modid = %d\n", rsp.modid()); printf("cmdid = %d\n", rsp.cmdid()); printf("host_size = %d\n", rsp.host_size()); for (int i = 0; i < rsp.host_size(); i++) { printf("-->ip = %u\n", rsp.host(i).ip()); printf("-->port = %d\n", rsp.host(i).port()); } //再請求 lars::GetRouteRequest req; req.set_modid(rsp.modid()); req.set_cmdid(rsp.cmdid()); std::string requestString; req.SerializeToString(&requestString); net_conn->send_message(requestString.c_str(), requestString.size(), lars::ID_GetRouteRequest); } int main(int argc, char **argv) { parse_option(argc, argv); event_loop loop; tcp_client *client; //創建客戶端 client = new tcp_client(&loop, option.ip, option.port, "lars_dns_test"); if (client == NULL) { fprintf(stderr, "client == NULL\n"); exit(1); } //客戶端成功建立連接，首先發送請求包 client->set_conn_start(on_connection); //設置服務端回應包處理業務 client->add_msg_router(lars::ID_GetRouteResponse, deal_get_route); loop.event_process(); return 0; } ``` ? ? 同時提供一個`Makefile`對客戶端進行編譯。 > lars_dns/test/Makefile ```makefile TARGET= lars_dns_test1 CXX=g++ CFLAGS=-g -O2 -Wall -Wno-deprecated BASE=../../base BASE_H=$(BASE)/include PROTO = $(BASE)/proto PROTO_H = $(BASE)/proto LARS_REACTOR=../../lars_reactor LARS_REACTOR_H =$(LARS_REACTOR)/include LARS_REACTOR_LIB=$(LARS_REACTOR)/lib -llreactor OTHER_LIB = -lpthread -ldl -lprotobuf SRC= ./src INC= -I./include -I$(BASE_H) -I$(LARS_REACTOR_H) -I$(PROTO_H) LIB= $(MYSQL_LIB) -L$(LARS_REACTOR_LIB) $(OTHER_LIB) OBJS = lars_dns_test1.o OBJS += $(PROTO)/lars.pb.o $(TARGET): $(OBJS) $(CXX) $(CFLAGS) -o $(TARGET) $(OBJS) $(INC) $(LIB) %.o: %.cpp $(CXX) $(CFLAGS) -c -o $@ $< $(INC) .PHONY: clean clean: -rm -f ./*.o $(TARGET) ``` 我們分別啟動`bin/lars_dns`進程，和`test/lars_dns_test1`進程 服務端 ```bash $ ./bin/lars_dns msg_router init... create 0 thread create 1 thread create 2 thread create 3 thread create 4 thread add msg cb msgid = 1 lars dns service .... begin accept begin accept [thread]: get new connection succ! modID = 1, cmdID = 1, ip = 3232235953, port = 7777 modID = 1, cmdID = 2, ip = 3232235954, port = 7776 modID = 2, cmdID = 1, ip = 3232235955, port = 7778 modID = 2, cmdID = 2, ip = 3232235956, port = 7779 modID = 1, cmdID = 1, ip = 3232235953, port = 7777 modID = 1, cmdID = 2, ip = 3232235954, port = 7776 modID = 2, cmdID = 1, ip = 3232235955, port = 7778 modID = 2, cmdID = 2, ip = 3232235956, port = 7779 read data from socket ``` 客戶端 ```bash $ ./lars_dns_test1 -h 127.0.0.1 -p 7778 msg_router init... do_connect EINPROGRESS add msg cb msgid = 2 connect 127.0.0.1:7778 succ! modid = 1 cmdid = 2 host_size = 1 -->ip = 3232235954 -->port = 7776 ``` --- ### 關于作者： 作者：`Aceld(劉丹冰)` mail: [danbing.at@gmail.com](mailto:danbing.at@gmail.com) github: [https://github.com/aceld](https://github.com/aceld) 原創書籍: [http://www.hmoore.net/@aceld](http://www.hmoore.net/@aceld)  >**原創聲明:未經作者允許請勿轉載, 如果轉載請注明出處**