更新时间:2024-06-26 GMT+08:00

C++

准备环境

以Linux Ubuntu系统为例,首先需要安装SSL相关工具。

  1. 安装openssl库。
    apt-get install libssl-dev
  2. 安装curl库。
    apt-get install libcurl4-openssl-dev

获取SDK

点此下载SDK与Demo

解压时选择解压到当前文件夹,解压后目录结构如下:

名称

说明

hasher.cpp

SDK代码

hasher.h

header.h

RequestParams.cpp

RequestParams.h

signer.cpp

signer.h

constants.h

Makefile

Makefile文件

main.cpp

示例代码

请求签名与API调用

  1. 在main.cpp中加入以下引用。

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    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <curl/curl.h>
    #include "signer.h"
    

  2. 生成一个新的Signer,将AK/SK分别填入。

    1. 本示例以AK和SK保存在环境变量中为例,运行本示例前请先在本地环境中设置环境变量HUAWEICLOUD_SDK_AK和HUAWEICLOUD_SDK_SK。以Linux系统为例在本地将已获取的AK/SK设置为环境变量。
      1. 打开终端,输入以下命令打开环境变量配置文件。

        vi ~/.bashrc

      2. 设置环境变量,保存文件并退出编辑器。
        export HUAWEICLOUD_SDK_AK="已获取AK值" 
        export HUAWEICLOUD_SDK_SK="已获取SK值" 
      3. 输入以下命令使配置文件生效。

        source ~/.bashrc

    2. 生成一个新的Signer,填入已设置的环境变量。
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      //Set the AK/SK to sign and authenticate the request.
      // Directly writing AK/SK in code is risky. For security, encrypt your AK/SK and store them in the configuration file or environment variables.
      // In this example, the AK/SK are stored in environment variables for identity authentication. Before running this example, set environment variables HUAWEICLOUD_SDK_AK and HUAWEICLOUD_SDK_SK.
      Signer signer(getenv("HUAWEICLOUD_SDK_AK"), getenv("HUAWEICLOUD_SDK_SK"));
      

  3. 生成一个新的RequestParams,指定方法名、域名、请求uri、查询字符串和body。

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    //Specify a request method, such as GET, PUT, POST, DELETE, HEAD, and PATCH.
    //Set a request URL.
    //Set parameters for the request URL.
    //Add a body if you have specified the PUT or POST method. Special characters, such as the double quotation mark ("), contained in the body must be escaped.
    RequestParams* request = new RequestParams("GET", "service.region.example.com", "/v1/{project_id}/vpcs",
            "limit=2", "");
    

  4. 添加需要签名的头域,或者其他用途的头域,如多项目场景中添加X-Project-Id,或者全局服务场景中添加X-Domain-Id。

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    //Add header parameters, for example, X-Domain-Id for invoking a global service and X-Project-Id for invoking a project-level service.
    request->addHeader("X-Project-Id", "xxx");
    

  5. 进行签名,执行此函数会将生成的签名头加入request变量中。

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    signer.createSignature(request);
    

  6. 使用curl库访问API,查看访问结果。

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    static size_t
    WriteMemoryCallback(void *contents, size_t size, size_t nmemb, void *userp)
    {
        size_t realsize = size * nmemb;
        struct MemoryStruct *mem = (struct MemoryStruct *)userp;
    
        mem->memory = (char*)realloc(mem->memory, mem->size + realsize + 1);
        if (mem->memory == NULL) {
            /* out of memory! */
            printf("not enough memory (realloc returned NULL)\n");
            return 0;
        }
    
        memcpy(&(mem->memory[mem->size]), contents, realsize);
        mem->size += realsize;
        mem->memory[mem->size] = 0;
    
        return realsize;
    }
    
    //send http request using curl library
    int perform_request(RequestParams* request)
    {
        CURL *curl;
        CURLcode res;
        struct MemoryStruct resp_header;
        resp_header.memory = (char*)malloc(1);
        resp_header.size = 0;
        struct MemoryStruct resp_body;
        resp_body.memory = (char*)malloc(1);
        resp_body.size = 0;
    
        curl_global_init(CURL_GLOBAL_ALL);
        curl = curl_easy_init();
    
        curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, request->getMethod().c_str());
        std::string url = "http://" + request->getHost() + request->getUri() + "?" + request->getQueryParams();
        curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
        struct curl_slist *chunk = NULL;
        std::set<Header>::iterator it;
        for (auto header : *request->getHeaders()) {
            std::string headerEntry = header.getKey() + ": " + header.getValue();
            printf("%s\n", headerEntry.c_str());
            chunk = curl_slist_append(chunk, headerEntry.c_str());
        }
        printf("-------------\n");
        curl_easy_setopt(curl, CURLOPT_HTTPHEADER, chunk);
        curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS, request->getPayload().c_str());
        curl_easy_setopt(curl, CURLOPT_NOBODY, 0L);
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteMemoryCallback);
        curl_easy_setopt(curl, CURLOPT_HEADERDATA, (void *)&resp_header);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void *)&resp_body);
        //curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
        res = curl_easy_perform(curl);
        if (res != CURLE_OK) {
            fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
        }
        else {
            long status;
            curl_easy_getinfo(curl, CURLINFO_HTTP_CODE, &status);
            printf("status %d\n", status);
            printf(resp_header.memory);
            printf(resp_body.memory);
        }
        free(resp_header.memory);
        free(resp_body.memory);
        curl_easy_cleanup(curl);
    
        curl_global_cleanup();
    
        return 0;
    }
    

  7. 运行make命令编译,得到可执行文件main,执行main文件,查看结果。