Object Storage Service:Descargar un archivo (SDK de C++)

Cuando se llama a la operación GetObject en un bucket, se aplica uno de los siguientes casos:

• Si la versión actual del objeto es una marca de eliminación, OSS devuelve 404 Not Found.

• Si especifica el versionId de un objeto en el parámetro de consulta, se devuelve la versión indicada. Si establece el versionId como "null", se devuelve la versión del objeto que tiene un versionId nulo.

• Si intenta recuperar una marca de eliminación al especificar su versionId, OSS devuelve 405 Method Not Allowed.

#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, such as examplebucket. */
    std::string BucketName = "examplebucket";
    /* Specify the full path of the object. The full path cannot contain the bucket name, such as exampledir/exampleobject.txt. */
    std::string ObjectName = "exampledir/exampleobject.txt";

    /* 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);

    /* Download the file to the local memory. */
    GetObjectRequest request(BucketName, ObjectName);
    request.setVersionId("yourObjectVersionId");
    auto outcome = client.GetObject(request);
    if (outcome.isSuccess()) {
        std::cout << "getObjectToBuffer" << " success, Content-Length:" << outcome.result().Metadata().ContentLength() << std::endl;
        /* Read the content of the downloaded object. */
        std::string content;
        *(outcome.result().Content()) >> content;
        std::cout << "getObjectToBuffer" << "content:" << content << std::endl;
        /* View the version ID of the downloaded object. */
        std::cout << "versionid:" << outcome.result().VersionId() << std::endl;
    }
    else {
            /* Handle the exception. */
            std::cout << "getObjectToBuffer fail" <<
        ",code:" << outcome.error().Code() <<
        ",message:" << outcome.error().Message() <<
        ",requestId:" << outcome.error().RequestId() << std::endl;
        return -1;
    }

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