Object Storage Service:Simple download

Usage notes

Before you run the sample code in this topic, you must create an OSSClient instance by using methods such as using a custom domain name or Security Token Service (STS). For more information, see Initialization.

Permissions

By default, an Alibaba Cloud account has full permissions. RAM users or RAM roles under an Alibaba Cloud account do not have any permissions by default. The Alibaba Cloud account or account administrator must grant operation permissions through RAM Policy or Bucket Policy.

Example

You can download an object as a local file or as NSData:

OSSGetObjectRequest * request = [OSSGetObjectRequest new];

// Specify the name of the bucket. Example: examplebucket. 
request.bucketName = @"examplebucket";
// Specify the full path of the object. Example: exampledir/exampleobject.txt. Do not include the bucket name in the full path. 
request.objectKey = @"exampledir/exampleobject.txt";

// Configure optional fields. 
request.downloadProgress = ^(int64_t bytesWritten, int64_t totalBytesWritten, int64_t totalBytesExpectedToWrite) {
    // Specify the number of bytes that are being downloaded, the number of bytes that are downloaded, and the total number of bytes that you want to download. 
    NSLog(@"%lld, %lld, %lld", bytesWritten, totalBytesWritten, totalBytesExpectedToWrite);
};
// request.range = [[OSSRange alloc] initWithStart:0 withEnd:99]; // bytes=0-99. Specify that the download range is from byte 0 to byte 99. 
// request.downloadToFileURL = [NSURL fileURLWithPath:@"<filepath>"]; // If you need to directly download the object to a file, specify the path of the file. 

OSSTask * getTask = [client getObject:request];

[getTask continueWithBlock:^id(OSSTask *task) {
    if (!task.error) {
        NSLog(@"download object success!");
        OSSGetObjectResult * getResult = task.result;
        NSLog(@"download result: %@", getResult.downloadedData);
    } else {
        NSLog(@"download object failed, error: %@" ,task.error);
    }
    return nil;
}];

// [getTask waitUntilFinished];

// [request cancel];

References

• For more information about the operation that you can call to perform simple download, see GetObject.

• For more information about how to initialize an OSSClient instance, see Initialization.