google protobuf是一個靈活的、高效的用於序列化數據的協議。相比較XML和JSON格式,protobuf更小、更快、更便捷。google protobuf是跨語言的,並且自帶了一個編譯器(protoc),只需要用它進行編譯,可以編譯成Java、python、C++、C#、Go等代碼,然後就可以直接使用,不需要再寫其他代碼,自帶有解析的代碼。更詳細的介紹見: Protocol Buffers
1、下載protobuf代碼 google/protobuf
2、安裝protobuf
tar -xvf protobuf
cd protobuf
./configure --prefix=/usr/local/protobuf
make
make check
make install
至此安裝完成^_^,下面是配置:
(1) vim /etc/profile,添加
export PATH=$PATH:/usr/local/protobuf/bin/ export PKG_CONFIG_PATH=/usr/local/protobuf/lib/pkgconfig/ 保存執行,source /etc/profile。同時在~/.profile中添加上面兩行代碼,否則會出現登錄用戶找不到protoc命令。 (2) 配置動態鏈接庫 vim /etc/ld.so.conf,在文件中添加/usr/local/protobuf/lib(注意: 在新行處添加),然後執行命令: ldconfig.proto文件是protobuf一個重要的文件,它定義了需要序列化數據的結構。使用protobuf的3個步驟是:
1 在.proto文件中定義消息格式
2 用protobuf編譯器編譯.proto文件
3 用C++/Java等對應的protobuf API來寫或者讀消息
該程序示例的大致功能是,定義一個Persion結構體和存放Persion的AddressBook,然後一個寫程序向一個文件寫入該結構體信息,另一個程序從文件中讀出該信息並打印到輸出中。
1 address.proto文件
package tutorial; message Persion { required string name = 1; required int32 age = 2; } message AddressBook { repeated Persion persion = 1; }
編譯.proto文件,執行命令: protoc -I=$SRC_DIR --cpp_out=$DST_DIR $SRC_DIR/addressbook.proto,示例中執行命令protoc --cpp_out=/tmp addressbook.proto ,會在/tmp中生成文件addressbook.pb.h和addressbook.pb.cc。
2 write.cpp文件,向文件中寫入AddressBook信息,該文件是二進制的
1 #include <iostream> 2 #include <fstream> 3 #include <string> 4 #include "addressbook.pb.h" 5 6 using namespace std; 7 8 void PromptForAddress(tutorial::Persion *persion) { 9 cout << "Enter persion name:" << endl; 10 string name; 11 cin >> name; 12 persion->set_name(name); 13 14 int age; 15 cin >> age; 16 persion->set_age(age); 17 } 18 19 int main(int argc, char **argv) { 20 //GOOGLE_PROTOBUF_VERIFY_VERSION; 21 22 if (argc != 2) { 23 cerr << "Usage: " << argv[0] << " ADDRESS_BOOL_FILE" << endl; 24 return -1; 25 } 26 27 tutorial::AddressBook address_book; 28 29 { 30 fstream input(argv[1], ios::in | ios::binary); 31 if (!input) { 32 cout << argv[1] << ": File not found. Creating a new file." << endl; 33 } 34 else if (!address_book.ParseFromIstream(&input)) { 35 cerr << "Filed to parse address book." << endl; 36 return -1; 37 } 38 } 39 40 // Add an address 41 PromptForAddress(address_book.add_persion()); 42 43 { 44 fstream output(argv[1], ios::out | ios::trunc | ios::binary); 45 if (!address_book.SerializeToOstream(&output)) { 46 cerr << "Failed to write address book." << endl; 47 return -1; 48 } 49 } 50 51 // Optional: Delete all global objects allocated by libprotobuf. 52 //google::protobuf::ShutdownProtobufLibrary(); 53 54 return 0; 55 }
編譯write.cpp文件,g++ addressbook.pb.cc write.cpp -o write `pkg-config --cflags --libs protobuf` (注意,這裡的`符號在鍵盤數字1鍵左邊,也就是和~是同一個按鍵)。
3 read.cpp文件,從文件中讀出AddressBook信息並打印
1 #include <iostream> 2 #include <fstream> 3 #include <string> 4 #include "addressbook.pb.h" 5 6 using namespace std; 7 8 void ListPeople(const tutorial::AddressBook& address_book) { 9 for (int i = 0; i < address_book.persion_size(); i++) { 10 const tutorial::Persion& persion = address_book.persion(i); 11 12 cout << persion.name() << " " << persion.age() << endl; 13 } 14 } 15 16 int main(int argc, char **argv) { 17 //GOOGLE_PROTOBUF_VERIFY_VERSION; 18 19 if (argc != 2) { 20 cerr << "Usage: " << argv[0] << " ADDRESS_BOOL_FILE" << endl; 21 return -1; 22 } 23 24 tutorial::AddressBook address_book; 25 26 { 27 fstream input(argv[1], ios::in | ios::binary); 28 if (!address_book.ParseFromIstream(&input)) { 29 cerr << "Filed to parse address book." << endl; 30 return -1; 31 } 32 input.close(); 33 } 34 35 ListPeople(address_book); 36 37 // Optional: Delete all global objects allocated by libprotobuf. 38 //google::protobuf::ShutdownProtobufLibrary(); 39 40 return 0; 41 }
編譯read.cpp文件,g++ addressbook.pb.cc read.cpp -o read `pkg-config --cflags --libs protobuf`
4 執行程序