c++ 调用restful API 示例

在C++中直接调用RESTful API通常不是直接操作，因为C++本身并不支持HTTP请求。但是，你可以通过一些库如cpr (C++ REST Client) 或 Poco C++ Libraries 来处理这样的任务。这里是一个基本的例子：

#include "poco/http_client.h"
#include "poco/http_client_request.h"
#include "poco/http_response.h"

using namespace Poco;

void callRESTAPI(const std::string& apiUrl, const std::string& method, const std::string& requestBody = "")
{
    try {
        HTTPClientSession session("example.com", 80);
        HTTPRequest request(Poco::HTTPRequest::HTTP_METHOD_GET, apiUrl, HTTPMessage::HTTP_1_1);

        if (method == "POST") {
            request.setMethod(HTTPRequest::HTTP_POST);
            request.setRequestBody(requestBody);
        }

        HTTPResponse response;
        session.sendRequest(request, response);
        
        // 检查响应状态码
        if (response.getStatus() == HTTPResponse::HTTP_OK) {
            std::cout << "Response body:\n" << response.stream().str();
        } else {
            std::cerr << "Error calling API: " << response.statusText() << ", status code: " << response.getStatus() << std::endl;
        }
    } catch (Exception& e) {
        std::cerr << "Error: " << e.displayText() << std::endl;
    }
}

int main()
{
    callRESTAPI("/api/resource", "GET");
    callRESTAPI("/api/resource", "POST", "{\"key\":\"value\"}");
    return 0;
}

在这个示例中，我们创建了一个`callRESTAPI`函数，它接受API URL、HTTP方法（GET或POST）以及可选的POST请求体。然后使用Poco库发送HTTP请求并处理响应。