mongocxx::change_stream Class Reference

Class representing a MongoDB change stream. More...

#include <change_stream.hpp>

Classes
class	iterator
	Class representing a MongoDB change stream iterator. More...

Public Member Functions
	change_stream (change_stream &&other) noexcept
	Move constructs a change_stream.
change_stream &	operator= (change_stream &&other) noexcept
	Move assigns a change_stream.
	~change_stream ()
	Destroys a change_stream.
iterator	begin () const
	A change_stream::iterator points to the beginning of any available notifications.
iterator	end () const
	A change_stream::iterator indicating stream exhaustion, meaning that no notifications are available from the stream.
bsoncxx::stdx::optional< bsoncxx::document::view >	get_resume_token () const
	Returns a resume token for this change stream.

Detailed Description

Class representing a MongoDB change stream.

Member Function Documentation

begin()

iterator mongocxx::change_stream::begin

(

)

const

A change_stream::iterator points to the beginning of any available notifications.

Each call to begin() advances to the next available notification. The state of all iterators is tracked by the change_stream itself, so advancing one iterator advances all iterators.

change_stream::begin() and the increment operators are blocking operations. They will not return until a notification is available, the max_await_time (from the options::change_stream) milliseconds have elapsed, or a server error is encountered.

When change_stream.begin() == change_stream.end(), no notifications are available. Each call to change_stream.begin() checks again for newly-available notifications.

Returns

The change_stream::iterator

Exceptions

Throws

mongocxx::query_exception if the query failed.

end()

iterator mongocxx::change_stream::end

(

)

const

A change_stream::iterator indicating stream exhaustion, meaning that no notifications are available from the stream.

Returns

The change_stream::iterator indicating exhaustion

get_resume_token()

bsoncxx::stdx::optional< bsoncxx::document::view > mongocxx::change_stream::get_resume_token

(

)

const

Returns a resume token for this change stream.

If the change stream has not been iterated, and either resume_after or start_after was specified in the options to this change stream, the specified value will be returned by this method. If neither resume_after or start_after was set on the options for this change stream, and it has not been iterated, this method will return no token.

Once this change stream has been iterated, this method will return the resume token of the most recently returned document in the stream, or a postBatchResumeToken if the current batch of documents has been exhausted.

See also

https://docs.mongodb.com/manual/changeStreams/#change-stream-resume-token

The returned document::view is valid for the lifetime of the stream and its data may be updated if the change stream is iterated after this function. The value may be copied to extend its lifetime or preserve the current resume token.

Returns

The token.

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The documentation for this class was generated from the following file:

• src/mongocxx/change_stream.hpp