mongocxx::v1::read_preference Class Reference

#include <mongocxx/v1/read_preference.hpp>

Description

Options related to a MongoDB Read Preference.

Supported fields include:

• hedge
• max_staleness ("maxStalenessSeconds")
• mode
• tags ("tag_sets")

See also

• Read Preference (MongoDB Manual)

Attention

This feature is experimental! It is not ready for use!

Public Types
enum class	read_mode
	The read preference mode. More...

Public Member Functions
	read_preference ()
	Default initialization.
	read_preference (read_preference &&other) noexcept
	Move constructor.
	read_preference (read_preference const &other)
	Copy construction.
	~read_preference ()
	Destroy this object.
bsoncxx::v1::stdx::optional< bsoncxx::v1::document::view >	hedge () const
	Return the current "hedge" field.
read_preference &	hedge (bsoncxx::v1::document::view v)
	Set the "hedge" field.
bsoncxx::v1::stdx::optional< std::chrono::seconds >	max_staleness () const
	Return the current "maxStalenessSeconds" field.
read_preference &	max_staleness (std::chrono::seconds v)
	Set the "maxStalenessSeconds" field.
read_mode	mode () const
	Return the current "mode" field.
read_preference &	mode (read_mode v)
	Set the "mode" field.
read_preference &	operator= (read_preference &&other) noexcept
	Move assignment.
read_preference &	operator= (read_preference const &other)
	Copy assignment.
bsoncxx::v1::array::view	tags () const
	Return the current "tag_sets" field.
read_preference &	tags (bsoncxx::v1::array::view v)
	Set the "tag_sets" field.
read_preference &	tags (bsoncxx::v1::document::view v)
	Set the "tag_sets" field.

Friends
bool	operator== (read_preference const &lhs, read_preference const &rhs)
	Compare equal when all supported fields compare equal.
bool	operator!= (read_preference const &lhs, read_preference const &rhs)
	Compare equal when all supported fields compare equal.

Member Enumeration Documentation

read_mode

enum class mongocxx::v1::read_preference::read_mode

strong

The read preference mode.

See also

• Read Preference (MongoDB Manual)

Attention

This feature is experimental! It is not ready for use!

Enumerator
k_primary	Primary member only (default).
k_primary_preferred	Primary member when available, secondary otherwise.
k_secondary	Secondary members only.
k_secondary_preferred	Secondary members when available, primary otherwise.
k_nearest	A random eligible member based on a specified latency threshold.

Constructor & Destructor Documentation

~read_preference()

mongocxx::v1::read_preference::~read_preference

(

)

Destroy this object.

read_preference() [1/3]

mongocxx::v1::read_preference::read_preference ( read_preference && other )

noexcept

Move constructor.

Postconditions:

• other is in an assign-or-destroy-only state.

read_preference() [2/3]

mongocxx::v1::read_preference::read_preference

(

read_preference const &

other

)

Copy construction.

read_preference() [3/3]

mongocxx::v1::read_preference::read_preference

(

)

Default initialization.

Postconditions:

• All supported fields are "unset" or zero-initialized.

Member Function Documentation

hedge() [1/2]

bsoncxx::v1::stdx::optional< bsoncxx::v1::document::view > mongocxx::v1::read_preference::hedge

(

)

const

Return the current "hedge" field.

Deprecated

Deprecated in MongoDB Server version 8.0.

hedge() [2/2]

read_preference & mongocxx::v1::read_preference::hedge

(

bsoncxx::v1::document::view

v

)

Set the "hedge" field.

Deprecated

Deprecated in MongoDB Server version 8.0.

max_staleness() [1/2]

bsoncxx::v1::stdx::optional< std::chrono::seconds > mongocxx::v1::read_preference::max_staleness

(

)

const

Return the current "maxStalenessSeconds" field.

Returns

An empty optional if the option is unset.

max_staleness() [2/2]

read_preference & mongocxx::v1::read_preference::max_staleness

(

std::chrono::seconds

v

)

Set the "maxStalenessSeconds" field.

Parameters

v	-1 is equivalent to "unset".

mode() [1/2]

read_mode mongocxx::v1::read_preference::mode

(

)

const

Return the current "mode" field.

mode() [2/2]

read_preference & mongocxx::v1::read_preference::mode

(

read_mode

v

)

Set the "mode" field.

Parameters

v	One of: read_mode::k_primary read_mode::k_primary_preferred read_mode::k_secondary read_mode::k_secondary_preferred read_mode::k_nearest

See also

• Read Preference Use Cases

operator=() [1/2]

read_preference & mongocxx::v1::read_preference::operator= ( read_preference && other )

noexcept

Move assignment.

Postconditions:

• other is in an assign-or-destroy-only state.

operator=() [2/2]

read_preference & mongocxx::v1::read_preference::operator=

(

read_preference const &

other

)

Copy assignment.

tags() [1/3]

bsoncxx::v1::array::view mongocxx::v1::read_preference::tags

(

)

const

Return the current "tag_sets" field.

tags() [2/3]

read_preference & mongocxx::v1::read_preference::tags

(

bsoncxx::v1::array::view

v

)

Set the "tag_sets" field.

tags() [3/3]

read_preference & mongocxx::v1::read_preference::tags

(

bsoncxx::v1::document::view

v

)

Set the "tag_sets" field.

Friends And Related Symbol Documentation

operator!=

bool operator!= ( read_preference const & lhs, read_preference const & rhs )

friend

Compare equal when all supported fields compare equal.

operator==

bool operator== ( read_preference const & lhs, read_preference const & rhs )

friend

Compare equal when all supported fields compare equal.

---

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

• mongocxx/v1/read_preference.hpp