httplib 库介绍与使用
说明：
cpp-httplib 是个开源的库，是一个c++封装的http库，使用这个库可以在linux、windows平台下完成http客户端、http服务端的搭建，这是一个多线程“阻塞”HTTP 库。
使用起来非常方便，只需要包含头文件httplib.h即可。
源码库地址：https://github.com/yhirose/cpp-httplib
httplib 库基本结构：
发送请求Request类的组成：
class Request
{
std::string method; // 请求方法
std::string path; // 请求路径
map<std::string, std::string> param; // 查询字符串(查询字符串中)
map<std::string, std::string> headers;// 键值对头部
std::string body; //正文
};
响应数据类Response的组成：
class Response
{
int status; //返回的状态码
map<std::string,std::string> headers; //返回的价值对头部
std::string body; //正文
};
服务端Server 类的组成：
class Server {
public:
using Handler = std::function<void(const Request &, Response &)>;
using HandlerWithContentReader = std::function<void(
const Request &, Response &, const ContentReader &content_reader)>;
using Expect100ContinueHandler =
std::function<int(const Request &, Response &)>;
Server();
virtual ~Server();
virtual bool is_valid() const;
Server &Get(const char *pattern, Handler handler);
Server &Post(const char *pattern, Handler handler);
Server &Post(const char *pattern, HandlerWithContentReader handler);
Server &Put(const char *pattern, Handler handler);
Server &Put(const char *pattern, HandlerWithContentReader handler);
Server &Patch(const char *pattern, Handler handler);
Server &Patch(const char *pattern, HandlerWithContentReader handler);
Server &Delete(const char *pattern, Handler handler);
Server &Delete(const char *pattern, HandlerWithContentReader handler);
Server &Options(const char *pattern, Handler handler);
客户端Client 类的组成：
class Client
{
//创建client
Client(host,port);
Get()
Post()
Put()
...
};
简单实例：
Server：
#define CPPHTTPLIB_OPENSSL_SUPPORT
#include "path/to/httplib.h"
// HTTP
httplib::Server svr;
// HTTPS
httplib::SSLServer svr;
svr.Get("/hi", [](const httplib::Request &, httplib::Response &res) {
res.set_content("Hello World!", "text/plain");
});
svr.listen("0.0.0.0", 8080);
Client：
#define CPPHTTPLIB_OPENSSL_SUPPORT
#include "path/to/httplib.h"
// HTTP
httplib::Client cli("http://cpp-httplib-server.yhirose.repl.co");
// HTTPS
httplib::Client cli("https://cpp-httplib-server.yhirose.repl.co");
auto res = cli.Get("/hi");
res->status;
res->body;
SSL Support：
SSL support 要用到 CPPHTTPLIB_OPENSSL_SUPPORT. libssl and libcrypto 的支持。
现在只有 httplib 1.1.1 支持ssl 服务器。
#define CPPHTTPLIB_OPENSSL_SUPPORT
#include "path/to/httplib.h"
// Server
httplib::SSLServer svr("./cert.pem", "./key.pem");
// Client
httplib::Client cli("https://localhost:1234"); // scheme + host
httplib::SSLClient cli("localhost:1234"); // host
// Use your CA bundle
cli.set_ca_cert_path("./ca-bundle.crt");
// Disable cert verification
cli.enable_server_certificate_verification(false);
g++ -o service service.cpp -I/usr/local/openssl/include -L/usr/local/openssl/lib -lssl -lcrypto -pthread
完整简单web例子：
#include <stdio.h>
#include <iostream>
#include <jsoncpp/json/json.h>
#include "httplib.h"
using namespace httplib;
using namespace std;
int g_val = 100;
void Get_CallBackFunc(const Request& req, Response& resp)
{
printf("%d\n", g_val);
cout << req.method << endl;
printf("i am Get_CallBackFunc\n");
const char* lp = "<html><h2>hello bite!</h2></html>";
resp.set_content(lp, strlen(lp), "text/html");
}
int main()
{
Server http_svr;
int a = 10;
http_svr.Get("/abc", Get_CallBackFunc);
http_svr.Post("/login", [](const Request& req, Response& resp){
cout << req.body << endl;
Json::Value resp_json;
resp_json["login_status"] = true;
Json::FastWriter w;
resp.body = w.write(resp_json);
resp.set_header("Content-Type", "application/json");
});
http_svr.set_mount_point("/", "./web");
http_svr.listen("0.0.0.0", 21010);
return 0;
}
完整简单upload例子：
#include "httplib.h"
#include <iostream>
#include <fstream>
using namespace httplib;
using namespace std;
int main(void)
{
Server svr;
svr.Post("/post", [](const Request &req, Response &res) {
auto music_file = req.get_file_value("music_file");
cout << "image file length: " << music_file.content.length() << endl
<< "image file name: " << music_file.filename << endl;
{
ofstream ofs(music_file.filename, ios::binary);
ofs << music_file.content;
}
res.set_content("done", "text/plain");
});
svr.set_mount_point("/", "./www");
/// listen
svr.listen("0.0.0.0", 9089);
}
编译brotli源码
1.1. 下载安装
下载 libbrotli, brotli
如果虚拟机可以上网，clone libbrotli 之后，就可以使用 autogen.sh 直接编译
git clone https://github.com/bagder/libbrotli
cd libbrotli
./autogen.sh && ./configure && make && make install如果虚拟机不能上网，可以将 brotli 也下载好之后，直接放在 libbrotli 的目录之下，目录结构:libbrotli/brotli/c
git clone https://github.com/bagder/libbrotli
git clone https://github.com/google/brotli.git
cd libbrotli
# ll brotli/c
./autogen.sh && ./configure && make && make install1.1.1. 编译问题解决
- Makefile.am: C objects in subdir but
AM_PROG_CC_C_O' not inconfigure.ac' - Libtool library used but `LIBTOOL' is undefined，我在centos6的环境下编译通过，在centos5的环境下没有编译通过（没有特别去搞el5的环境，猜测可能需要升级libtool）。
在configure.am中添加 AM_PROG_CC_C_O
AC_PROG_CC
AM_PROG_CC_C_O1.2. 编译示例代码
上面的编译过程之后，会生成了对应的静态库和动态库，在 libbrotli 目录的 .libs 目录下。也可以直接使用过来作为库的方式加载。（后续准备写一个简单的测试例子来验证）
gcc -g -o brotli brotli.c -I. -I. -I.. -I../brotli/c/include ../.libs/libbrotlienc.so ../.libs/libbrotlidec.so -lm
gcc -g -o brotli brotli.c -I. -I. -I.. -I../brotli/c/include libbrotlienc.a libbrotlidec.a -lm1.3. 应用实例
# 压缩：压缩等级从0-11
time brotli -q 0 /www/docs/100M.file -o 100M.file.C
real 0m0.344s
user 0m0.271s
sys 0m0.072s
# 解压
time brotli -d 100M.file.C -o 100M.file
real 0m0.552s
user 0m0.392s
sys 0m0.159s
# 最终处理结果
ll 100M.file* -h
-rw-r--r-- 1 root root 100M Nov 6 2018 100M.file
-rw-r--r-- 1 root root 89K Nov 6 2018 100M.file.C1.4. 使用源码生成动静态库
./autogen.sh && ./configure --prefix=/home/xxx/brotli/libbrotli-master/target && make && make install
ll target/lib/*
-rw-r--r-- 1 root root 487628 Aug 16 11:19 target/lib/libbrotlidec.a
-rw-r--r-- 1 root root 3466066 Aug 16 11:19 target/lib/libbrotlienc.a
ls target/include/brotli/
decode.h encode.h port.h types.h
将静态库和include里面的.h文件拷贝出来，就可以用来编译自己的程序了，也可以移植到自己的程序中，比如网上资料最多的 nginx。 我工作用的是squid，也是通过这种方式支持的
gcc -g -o test_brotli test_brotli.c -I../target/brotli/include ../target/lib/libbrotlienc.a -lm
# test_brotli.c, 程序设计其实有问题，不过这里贴出来只是作为给大家编译用的测试demo
#include "brotli/encode.h"
#include "brotli/decode.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int
test_brotli_compress()
{
int is_ok = 1;
BrotliEncoderState* s = BrotliEncoderCreateInstance(NULL, NULL, NULL);
if (!s) {
fprintf(stderr, "out of memory\n");
return 0;
}
int quality = 1;
int lgwin = 22;
BrotliEncoderSetParameter(s, BROTLI_PARAM_QUALITY, quality);
BrotliEncoderSetParameter(s, BROTLI_PARAM_LGWIN, lgwin);
uint8_t* input_buf = (uint8_t*)malloc(1024);
uint8_t* out_buf = (uint8_t*)malloc(4096);
size_t available_in = 0; /* length of real data */
size_t available_out = 1024; /* length of buf befor call compress, and length of remain size of buf after compress */
const uint8_t* next_in = NULL; /* start of in buff */
uint8_t* next_out = NULL; /* start of out buff */
strcpy((char *)input_buf, "abcdefghijklmnopqrstuvwxyz");
next_in = input_buf; /* actually data must be binary data */
available_in = strlen("abcdefghijklmnopqrstuvwxyz");
available_out = 1024;
next_out = out_buf;
if (!BrotliEncoderCompressStream(s, BROTLI_OPERATION_PROCESS, &available_in, &next_in, &available_out, &next_out, NULL)) {
/* Should detect OOM? */
fprintf(stderr, "failed to compress data [%s]\n", "abcdefghijklmnopqrstuvwxyz");
is_ok = 0;
goto failed;
}
next_in = NULL;
available_in = 0;
if (available_out != 1024) {
next_out = out_buf + (1024 - available_out); /* buf + out_size */
available_out = 1024;
}
if (!BrotliEncoderCompressStream(s, BROTLI_OPERATION_FINISH, &available_in, &next_in, &available_out, &next_out, NULL)) {
/* Should detect OOM? */
fprintf(stderr, "failed to compress data [%s]\n", "0123456789");
is_ok = 0;
goto failed;
}
if (BrotliEncoderIsFinished(s)) is_ok = 1;
BrotliEncoderDestroyInstance(s);
failed:
free(input_buf);
free(input_buf2);
free(out_buf);
return is_ok;
}
int main()
{
test_brotli_compress();
return 0;
}1.5. 写在最后
如果大家觉有用，可以留言。后续可能会再补充在支持过程中遇到的其他问题
更新时间: 2019.08.16
