Object Storage Service:Upload callbacks (C++ SDK)

Usage notes

• 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.

Sample code

The following code provides an example of how to configure an upload callback:

#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, for 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, for 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 full path of the object. The full path cannot include the bucket name. For example, exampledir/exampleobject.txt. */
    std::string ObjectName = "exampledir/exampleobject.txt";
    /* Specify the URL of your callback server. */
    std::string ServerName = "https://example.aliyundoc.com:23450";

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

    ClientConfiguration conf;
    conf.signatureVersion = SignatureVersionType::V4;
    /* Obtain access credentials from environment variables. Before you run this sample 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>();
    *content << "Thank you for using Alibaba Cloud Object Storage Service!";

    /* Set the upload callback parameters. */
    std::string callbackBody = "bucket=${bucket}&object=${object}&etag=${etag}&size=${size}&mimeType=${mimeType}&my_var1=${x:var1}";
    ObjectCallbackBuilder builder(ServerName, callbackBody, "", ObjectCallbackBuilder::Type::URL);
    std::string value = builder.build();
    ObjectCallbackVariableBuilder varBuilder;
    varBuilder.addCallbackVariable("x:var1", "value1");
    std::string varValue = varBuilder.build();
    PutObjectRequest request(BucketName, ObjectName, content);
    request.MetaData().addHeader("x-oss-callback", value);
    request.MetaData().addHeader("x-oss-callback-var", varValue);
    auto outcome = client.PutObject(request);

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

References

For more information about the API operation for upload callbacks, see Callback.