How to create and delete folders by using C++ - Object Storage Service

Object Storage Service (OSS) uses a flat structure to store data as objects in buckets, which is different from the hierarchical structure of traditional file systems. To simplify object grouping and permission management, you can organize objects into a folder hierarchy.

Precautions

In this topic, the public endpoint of the China (Hangzhou) region is used. If you want to access OSS from other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about OSS regions and endpoints, see Regions and endpoints.
In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient by using custom domain names or Security Token Service (STS), see Create an OSSClient instance.

Create a folder

The following code creates the `exampledir` folder.

#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;

int main(void)
{
    /* Initialize the OSS account information. */
            
    /* Set yourEndpoint to the endpoint of the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. */
    std::string Endpoint = "yourEndpoint";
    /* Set yourRegion to the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou. */
    std::string Region = "yourRegion";
    /* Specify the bucket name. For example, examplebucket. */
    std::string BucketName = "examplebucket";
    /* Specify the folder name. The name must end with a forward slash (/). For example, exampledir/. */
    std::string DirName = "exampledir/";

    /* Initialize network resources. */
    InitializeSdk();

    ClientConfiguration conf;
    conf.signatureVersion = SignatureVersionType::V4;
    /* Obtain access credentials from environment variables. Before you run this code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set. */
    auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
    OssClient client(Endpoint, credentialsProvider, conf);
    client.SetRegion(Region);
    std::shared_ptr<std::iostream> content = std::make_shared<std::stringstream>();
    PutObjectRequest request(BucketName, DirName, content, ObjectMetaData());

    /* Create a folder. */
    auto outcome = client.PutObject(request);

    if (!outcome.isSuccess()) {
        /* Handle the exception. */
        std::cout << "PutObject fail" <<
        ",code:" << outcome.error().Code() <<
        ",message:" << outcome.error().Message() <<
        ",requestId:" << outcome.error().RequestId() << std::endl;
        return -1;
    }

    /* Release network resources. */
    ShutdownSdk();
    return 0;
}

Delete a folder

Warning

When you delete a folder, all its subfolders and files are also deleted. Proceed with caution.

The following code shows how to delete the `exampledir` folder and all the files in it.

#include <alibabacloud/oss/OssClient.h>
using namespace AlibabaCloud::OSS;

int main(void)
{
    /* Initialize the OSS account information. */
            
    /* Set yourEndpoint to the endpoint of the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. */
    std::string Endpoint = "yourEndpoint";
    /* Set yourRegion to the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou. */
    std::string Region = "yourRegion";
    /* Specify the bucket name. For example, examplebucket. */
    std::string BucketName = "examplebucket";    
    /* Specify the name of the folder to delete. */
    std::string keyPrefix = "exampledir/";

    /* Initialize network resources. */
    InitializeSdk();

    ClientConfiguration conf;
    conf.signatureVersion = SignatureVersionType::V4;
    /* Obtain access credentials from environment variables. Before you run this code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set. */
    auto credentialsProvider = std::make_shared<EnvironmentVariableCredentialsProvider>();
    OssClient client(Endpoint, credentialsProvider, conf);
    client.SetRegion(Region);

    std::string nextMarker = "";
    bool isTruncated = false;
    do {
            /* List objects. */
            ListObjectsRequest request(BucketName);           
            request.setPrefix(keyPrefix);
            request.setMarker(nextMarker);
            auto outcome = client.ListObjects(request);

            if (!outcome.isSuccess()) {
                /* Handle the exception. */
                std::cout << "ListObjects fail" <<
                ",code:" << outcome.error().Code() <<
                ",message:" << outcome.error().Message() <<
                ",requestId:" << outcome.error().RequestId() << std::endl;
                break;
            }
            for (const auto& object : outcome.result().ObjectSummarys()) {
                DeleteObjectRequest request(BucketName, object.Key());
                /* Delete the folder and all objects in it. */
                auto delResult = client.DeleteObject(request);
            }
            nextMarker = outcome.result().NextMarker();
            isTruncated = outcome.result().IsTruncated();
    } while (isTruncated);

    /* Release network resources. */
    ShutdownSdk();
    return 0;
}

References

For information about the API operation to create a folder, see PutObject.
For information about the API operation to delete a folder, see DeleteObject.