Configure Referer-based hotlink protection for OSS using the C++ SDK - Object Storage Service

You can use the C++ software development kit (SDK) to configure access rules in Object Storage Service (OSS) based on the Referer request header. You can set a Referer whitelist or blacklist, and specify whether to allow requests that have an empty Referer. These rules block specified Referers from accessing your OSS files. This prevents other websites from hotlinking your files and reduces unnecessary traffic costs.

Precautions

Before you configure hotlink protection, make sure that you familiarize yourself with this feature. For more information, see Hotlink protection.
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.
To configure hotlink protection, you must have the oss:PutBucketReferer permission. To query hotlink protection configurations, you must have the oss:GetBucketReferer permission. For more information, see Attach a custom policy to a RAM user.

Set hotlink protection

The following sample code provides an example on how to configure hotlink protection for a bucket:

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

int main(void)
{
    /* Initialize 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";
    /* Set the bucket name, for example, examplebucket. */
    std::string BucketName = "examplebucket";

    /* 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);

    /* Set hotlink protection. */
    SetBucketRefererRequest request(BucketName);
    request.addReferer("http://www.aliyun.com");
    request.addReferer("https://www.aliyun.com");
    /* request.addReferer("https://www.alibabacloud.com/help");*/
    /* request.addReferer("http://www.?.aliyuncs.com");*/
    request.setAllowEmptyReferer(true);

    auto outcome = client.SetBucketReferer(request);

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

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

Get the hotlink protection configuration

The following sample code provides an example on how to query the hotlink configurations of a bucket:

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

int main(void)
{
    /* Initialize 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";
    /* Set the bucket name, for example, examplebucket. */
    std::string BucketName = "examplebucket";

    /* 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);


    /* Get hotlink protection information. */
    GetBucketRefererRequest request(BucketName);
    auto outcome = client.GetBucketReferer(request);

    if (outcome.isSuccess()) {
        std::cout << " GetBucketReferer success, AllowEmptyReferer: " << outcome.result().AllowEmptyReferer() <<
        " ,Referer size: " << outcome.result().RefererList().size() << std::endl;
    }
    else { 
        /* Handle exceptions. */
        std::cout << "GetBucketReferer fail" <<
        ",code:" << outcome.error().Code() <<
        ",message:" << outcome.error().Message() <<
        ",requestId:" << outcome.error().RequestId() << std::endl;
        return -1;
    }

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

Delete hotlink protection rules

The following sample code provides an example on how to delete the hotlink protection configurations of a bucket:

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

int main(void)
{
    /* Initialize 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";
    /* Set the bucket name, for example, examplebucket. */
    std::string BucketName = "examplebucket";

    /* 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);

    /* Delete hotlink protection rules. You cannot directly delete the rules. Instead, create a new rule that allows empty Referers to overwrite the previous rules. */
    SetBucketRefererRequest request(BucketName);
    request.setAllowEmptyReferer(true);

    auto outcome = client.SetBucketReferer(request);

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

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

References

For the complete sample code for hotlink protection, see GitHub.
For more information about the API operation to set hotlink protection, see PutBucketReferer.
For more information about the API operation to retrieve the hotlink protection configuration, see GetBucketReferer.