(minIO) aws sdk for C++

问题描述:

需要用C++进行minIO上传和下载，结果发现minIO SDK不支持C++，可以采用aws SDK进行上传和下载，因为minIO是遵循aws S3协议的。

解决办法

1. 下载aws sdk for c++源码:
   我下的是: https://github.com/aws/aws-sdk-cpp/archive/1.0.164.tar.gz 最新已经到1.7了，但是1.7需要从网上下依赖包，由于内网环境，因此下1.0就够了

https://github.com/aws/aws-sdk-cpp

2. windowns环境下安装cmake和git
   自行下载和安装
3. 解压aws-sdk-cpp-1.0.164
4. 创建编译路径，并编译生成项目

mkdir D:\tmp\build
cd D:\tmp\build
cmake D:xxx\xxx\aws-sdk-cpp-1.0.164 -G "Visual Studio 12 2013 Win64"

-G 是指定用visual studio进行编译，默认是会选择本机最新的vs环境编译，并且默认是x86的

5. 编译完成后打开build下面的AWSSDK.sln
6. 选择aws-cpp-sdk-s3工程进行编译，生成如下文件

aws-cpp-sdk-core.lib
aws-cpp-sdk-s3.lib
aws-cpp-sdk-core.dll
aws-cpp-sdk-s3.dll

这就是项目中需要的库

7. 把aws-sdk-cpp-1.0.164里include中aws-cpp-sdk-s3和aws-cpp-sdk-core的头文件考到项目中
8. 实现上传下载

#define USE_IMPORT_EXPORT
#include 
#include 
#include "aws\s3\S3Client.h"
#include "aws\core\Aws.h"
#include "aws\core\auth\AWSCredentialsProvider.h"
using namespace Aws::S3;
using namespace Aws::S3::Model;

#include "aws\s3\model\PutObjectRequest.h"
#include "aws\s3\model\GetObjectRequest.h"

bool uploadfile(std::string BucketName, std::string objectKey, std::string pathkey)
{
    Aws::SDKOptions m_options;
    S3Client * m_client = { NULL };

    Aws::InitAPI(m_options);
    Aws::Client::ClientConfiguration cfg;
    cfg.endpointOverride = "192.168.1.1:9000";  // S3服务器地址和端口
    cfg.scheme = Aws::Http::Scheme::HTTP;
    cfg.verifySSL = false;
    //Aws::Auth::AWSCredentials cred("RPW421T9GSIO4A45Y9ZR", "2owKYy9emSS90Q0pXuyqpX1OxBCyEDYodsiBemcq");  // 认证的Key
    m_client = new S3Client(Aws::Auth::AWSCredentials("test", "12345678"), cfg, false, false);

    PutObjectRequest putObjectRequest;
    putObjectRequest.WithBucket(BucketName.c_str()).WithKey(objectKey.c_str());
    auto input_data = Aws::MakeShared("PutObjectInputStream", pathkey.c_str(), std::ios_base::in | std::ios_base::binary);
    putObjectRequest.SetBody(input_data);
    auto putObjectResult = m_client->PutObject(putObjectRequest);
    if (putObjectResult.IsSuccess())
    {
        std::cout << "Done!" << std::endl;
        return true;
    }
    else
    {
        std::cout << "PutObject error: " <<
        putObjectResult.GetError().GetExceptionName() << " " <<
        putObjectResult.GetError().GetMessage() << std::endl;
        return false;
    }

    if (m_client != nullptr)
    {
        delete m_client;
        m_client = NULL;
    }
    Aws::ShutdownAPI(m_options);
}

bool downloadfile(std::string BucketName, std::string objectKey, std::string pathkey)
{
    Aws::SDKOptions m_options;
    S3Client * m_client = { NULL };

    Aws::InitAPI(m_options);
    Aws::Client::ClientConfiguration cfg;
    cfg.endpointOverride = "192.168.1.1:9000";  // S3服务器地址和端口
    cfg.scheme = Aws::Http::Scheme::HTTP;
    cfg.verifySSL = false;
    //Aws::Auth::AWSCredentials cred("RPW421T9GSIO4A45Y9ZR", "2owKYy9emSS90Q0pXuyqpX1OxBCyEDYodsiBemcq");  // 认证的Key
    m_client = new S3Client(Aws::Auth::AWSCredentials("test", "12345678"), cfg, false, false);

    Aws::S3::Model::GetObjectRequest object_request;
    object_request.WithBucket(BucketName.c_str()).WithKey(objectKey.c_str());
    auto get_object_outcome = m_client->GetObject(object_request);
    if (get_object_outcome.IsSuccess())
    {
        Aws::OFStream local_file;
        local_file.open(pathkey.c_str(), std::ios::out | std::ios::binary);
        local_file << get_object_outcome.GetResult().GetBody().rdbuf();
        std::cout << "Done!" << std::endl;
        return true;
    }
    else
    {
        std::cout << "GetObject error: " <<
            get_object_outcome.GetError().GetExceptionName() << " " <<
            get_object_outcome.GetError().GetMessage() << std::endl;
        return false;
    }

    if (m_client != nullptr)
    {
        delete m_client;
        m_client = NULL;
    }
    Aws::ShutdownAPI(m_options);

    return true;
}

遇到的问题

• 在下载的时候编译报错如下:
  error LNK2001: 无法解析的外部符号 "char const * const Aws::Http::CONTENT_TYPE_HEADER" (?CONTENT_TYPE_HEADER@Http@Aws@@3PEBDEB)
  解决办法:
  必须#define USE_IMPORT_EXPORT在应用程序中也包含任何内容之前进行定义, 定义需要在aws头文件引入之前。
  之后，AWS_CORE_API 在Core_EXPORTS.h中正确定义为_declspec(dllimport)
  不知道为什么这是必要的，为什么没有在文档中提及。

参考: https://github.com/aws/aws-sdk-cpp/issues/1235