Copy objects

Copy a small object

You can use CopyObject to copy an object that is up to 1 GB in size from a source bucket to a destination bucket within the same region.

• By default, the x-oss-copy-source header in a CopyObject request specifies the current version of the object to copy. If the current version of the object is a delete marker, Object Storage Service (OSS) returns 404, which indicates that the object does not exist. You can add a version ID to x-oss-copy-source to copy the specified object version. Delete markers cannot be copied.
• You can copy a previous version of an object to the same bucket. The copied previous version becomes the new version of the object. This way, the previous version of the object is recovered.
• If versioning is enabled for the destination bucket, OSS generates a unique version ID for the destination object. The version ID is returned in the response as the x-oss-version-id header value. If versioning is not enabled or is suspended for the destination bucket, OSS generates a version whose version ID is null for the destination object and the generated version overwrites the original version whose version ID is null.
• If versioning is not enabled for the destination bucket, you can copy appendable objects. If versioning is enabled or suspended for the destination bucket, you cannot copy appendable objects.

# -*- coding: utf-8 -*-
import oss2
# The AccessKey pair of an Alibaba Cloud account has permissions on all API operations. Using these credentials to perform operations in OSS is a high-risk operation. We recommend that you use a RAM user to call API operations or perform routine O&M. To create a RAM user, log on to the RAM console. 
auth = oss2.Auth('yourAccessKeyId', 'yourAccessKeySecret')
# Specify the name of the source bucket. Example: srcexamplebucket. 
src_bucket_name = 'srcexamplebucket'
# Specify the name of the destination bucket. The destination bucket must be in the same region as the source bucket. Example: destexamplebucket. 
# If you copy an object within a bucket, make sure that you specify the same bucket name for the source and destination buckets. 
dest_bucket_name = 'destexamplebucket'
# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
bucket = oss2.Bucket(auth, 'yourEndpoint', dest_bucket_name)

# Specify the full path of the source object. Example: srcexampledir/exampleobject.txt. The full path cannot contain the bucket name. 
src_object_name = 'srcexampledir/exampleobject.txt'
# Specify the full patch of the destination object. Example: destexampledir/exampleobject.txt. The full path cannot contain the bucket name. 
# If you copy an object within a bucket, make sure that you specify the same bucket name for the source and destination buckets. 
dest_object_name = 'destexampledir/exampleobject.txt'
# Specify the version ID of the source object. 
versionId = 'CAEQMxiBgICAof2D0BYiIDJhMGE3N2M1YTI1NDQzOGY5NTkyNTI3MGYyMzJm****'

# Copy the specified version of the object. 
params = dict()
params['versionId'] = versionId

# Copy the object from the source bucket to the destination bucket. 
result = bucket.copy_object(src_bucket_name, src_object_name, dest_object_name, params=params)
# View the response. If the return value is 200, the source object is copied to the destination bucket. 
print('result.status:', result.status)

For more information about how to copy small objects, see CopyObject.

Copy a large object

To copy an object that is larger than 1 GB in size, you must split the object into parts and copy the parts by using UploadPartCopy.

If versionId is not specified in the request and the current version of the source object is a delete marker, OSS returns 404 Not Found. If versionId is specified in the request and the specified version of the source object is a delete marker, OSS returns 400 Bad Request.

# -*- coding: utf-8 -*-
import os
import oss2
from oss2 import determine_part_size
from oss2.models import PartInfo

# The AccessKey pair of an Alibaba Cloud account has permissions on all API operations. Using these credentials to perform operations in OSS is a high-risk operation. We recommend that you use a RAM user to call API operations or perform routine O&M. To create a RAM user, log on to the RAM console. 
auth = oss2.Auth('yourAccessKeyId', 'yourAccessKeySecret')
# Specify the name of the source bucket. Example: srcexamplebucket. 
src_bucket_name = 'srcexamplebucket'
# Specify the name of the destination bucket. The destination bucket must be in the same region as the source bucket. Example: destexamplebucket. 
# If you copy an object within a bucket, make sure that you specify the same bucket name for the source and destination buckets. 
dest_bucket_name = 'destexamplebucket'
# Specify the endpoint of the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com. 
bucket = oss2.Bucket(auth, 'yourEndpoint', dest_bucket_name)
# If you copy an object within a bucket, comment out this line of code and change src_bucket in src_bucket_name to bucket. 
src_bucket = oss2.Bucket(auth, 'yourEndpoint', src_bucket_name)

# Specify the full path of the source object. Example: srcexampledir/exampleobject.txt. The full path cannot contain the bucket name. 
src_object_name = 'srcexampledir/exampleobject.txt'
# Specify the full path of the destination object. Example: destexampledir/exampleobject.txt. The full path cannot contain the bucket name. 
dest_object_name = 'destexampledir/exampleobject.txt'
# Specify the version ID of the source object. 
versionId = 'CAEQQhiBgMC5kZDE4RciIGZmNzdlYzRjYzRkODQwYjQ5ZDE0Njg5MWM0ODQzNDg3'

params = dict()
params['versionId'] = versionId

# Query the size of the specified version of the source object. If you copy an object within a bucket, change src_bucket to bucket. 
head_info = src_bucket.head_object(src_object_name, params=params)
total_size = head_info.content_length
print('src object size:', total_size)

# Use the determine_part_size method to determine the part size. 
part_size = determine_part_size(total_size, preferred_size=100 * 1024)
print('part_size:', part_size)

# Initiate a multipart upload task. 
upload_id = bucket.init_multipart_upload(dest_object_name).upload_id
parts = []

# Upload the parts one by one. 
part_number = 1
offset = 0
while offset < total_size:
    num_to_upload = min(part_size, total_size - offset)
    end = offset + num_to_upload - 1
    result = bucket.upload_part_copy(src_bucket_name, src_object_name, (offset, end), dest_object_name, upload_id, part_number, params=params)
    # Save the part information. 
    parts.append(PartInfo(part_number, result.etag))

    offset += num_to_upload
    part_number += 1

# Complete the multipart upload task. 
result = bucket.complete_multipart_upload(dest_object_name, upload_id, parts)
# Display the version ID of the destination object. 
print('result version id:', result.versionid)
# Query the metadata of the destination object. 
head_info = bucket.head_object(dest_object_name)
# Query the size of the destination object. 
dest_object_size = head_info.content_length
print('dest object size:', dest_object_size)
# Compare the sizes between the source and destination objects. 
assert dest_object_size == total_size

For more information about multipart copy, see UploadPartCopy.