C++ API代理示例

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#include <curl/curl.h>
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#include <string>
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#include <iostream>
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#include <nlohmann/json.hpp>
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static size_t Write(void* contents, size_t size, size_t nmemb, void* userp){
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  ((std::string*)userp)->append((char*)contents, size*nmemb);
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  return size*nmemb;
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}
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int main(){
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  std::string api = "http://ip.16yun.cn:817/myip/pl/<ORDER_ID>/?s=<ORDER_SIGN>&u=<USER>&format=json";
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  CURL* curl = curl_easy_init();
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  std::string buf;
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  if(!curl) return 1;
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  curl_easy_setopt(curl, CURLOPT_URL, api.c_str());
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  curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, Write);
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  curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buf);
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  CURLcode res = curl_easy_perform(curl);
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  if(res != CURLE_OK){ std::cerr << "API失败: " << curl_easy_strerror(res) << std::endl; return 1; }
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  curl_easy_cleanup(curl);
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  // 使用 nlohmann/json 解析返回的 JSON
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  std::string ip;
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  int port = 0;
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  try {
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    auto j = nlohmann::json::parse(buf);
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    if (j.is_array() && !j.empty()) {
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      ip = j.at(0).at("ip").get<std::string>();
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      port = j.at(0).at("port").get<int>();
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    } else if (j.is_object()) {
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      ip = j.at("ip").get<std::string>();
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      port = j.at("port").get<int>();
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    } else {
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      std::cerr << "解析失败: 返回 JSON 结构不符合预期" << std::endl;
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      return 1;
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    }
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  } catch (const std::exception& e) {
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    std::cerr << "解析失败: " << e.what() << std::endl;
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    return 1;
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  }
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  // 使用代理访问 httpbin
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  std::string page;
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  curl = curl_easy_init();
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  if(!curl) return 1;
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  curl_easy_setopt(curl, CURLOPT_URL, "https://httpbin.org/ip");
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  std::string proxy = std::string("http://") + ip + ":" + std::to_string(port);
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  curl_easy_setopt(curl, CURLOPT_PROXY, proxy.c_str());
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  curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, Write);
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  curl_easy_setopt(curl, CURLOPT_WRITEDATA, &page);
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  res = curl_easy_perform(curl);
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  if(res != CURLE_OK){ std::cerr << "访问失败: " << curl_easy_strerror(res) << std::endl; return 1; }
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  curl_easy_cleanup(curl);
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  std::cout << page << std::endl;
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  return 0;
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}