google::cloud::storage::ObjectRewriter Class Reference

Complete long running object rewrite operations. More...

#include <google/cloud/storage/object_rewriter.h>

Public Member Functions
	ObjectRewriter (std::shared_ptr< internal::RawClient > client, internal::RewriteObjectRequest request)
StatusOr< RewriteProgress >	Iterate ()
	Perform one iteration in the rewrite. More...
StatusOr< RewriteProgress >	CurrentProgress () const
	The current progress on the rewrite operation. More...
StatusOr< ObjectMetadata >	Result ()
	Iterate until the operation completes using a callback to report progress. More...
template<typename Functor , typename std::enable_if< google::cloud::internal::is_invocable< Functor, StatusOr< RewriteProgress > >::value, int >::type = 0>
StatusOr< ObjectMetadata >	ResultWithProgressCallback (Functor cb)
	Iterate until the operation completes using a callback to report progress. More...
std::string const &	token () const
	The current rewrite token. More...

Detailed Description

Complete long running object rewrite operations.

The Client::RewriteObject() operation allows applications to copy objects across location boundaries, and to rewrite objects with different encryption keys. In some circumstances it may take multiple calls to the service to complete a rewrite, this class encapsulates the state of a partial copy.

Constructor & Destructor Documentation

ObjectRewriter()

google::cloud::storage::ObjectRewriter::ObjectRewriter	(	std::shared_ptr< internal::RawClient >	client,
		internal::RewriteObjectRequest	request
	)

Member Function Documentation

CurrentProgress()

StatusOr< RewriteProgress > google::cloud::storage::ObjectRewriter::CurrentProgress ( ) const

inline

The current progress on the rewrite operation.

Iterate()

StatusOr< RewriteProgress > google::cloud::storage::ObjectRewriter::Iterate

(

)

Perform one iteration in the rewrite.

Returns

The progress after the iteration. If the rewrite has completed the application can use Result() to examine the metadata for the newly created object.

Result()

StatusOr< ObjectMetadata > google::cloud::storage::ObjectRewriter::Result ( )

inline

Iterate until the operation completes using a callback to report progress.

Note

This operation blocks until the copy is finished. For very large objects that could take substantial time. Applications may need to persist the rewrite operation. Some applications may want to wrap this call with std::async, and run the copy on a separate thread.

Returns

the object metadata once the copy completes.

ResultWithProgressCallback()

template<typename Functor , typename std::enable_if< google::cloud::internal::is_invocable< Functor, StatusOr< RewriteProgress > >::value, int >::type = 0>

StatusOr< ObjectMetadata > google::cloud::storage::ObjectRewriter::ResultWithProgressCallback ( Functor  cb )

inline

Iterate until the operation completes using a callback to report progress.

Note

This operation blocks until the copy is finished. For very large objects that could take substantial time. Applications may need to persist the rewrite operation. Some applications may want to wrap this call with std::async, and run the copy on a separate thread.

Parameters

cb	the callback object.

Template Parameters

Functor

the type of the callback object. It must satisfy: std:is_invocable<Functor, StatusOr<RewriteProgress>>:: value == true.

Returns

the object metadata once the copy completes.

token()

std::string const & google::cloud::storage::ObjectRewriter::token ( ) const

inline

The current rewrite token.

Applications can save the token of partially completed rewrites, and restart those operations using Client::CopyObjectRestart, even if the application has terminated. It is up to the application to preserve all the other information for the request, including source and destination buckets, encryption keys, and any preconditions affecting the request.

Note

For rewrites that have not started the token is an empty string. For rewrites that have completed the token is also an empty string. The application should preserve other information (such as the RewriteProgress) to avoid repeating a rewrite.