Struct mongodb::options::ReadPreferenceOptions

#[non_exhaustive]
pub struct ReadPreferenceOptions {
    pub tag_sets: Option<Vec<TagSet>>,
    pub max_staleness: Option<Duration>,
    pub hedge: Option<HedgedReadOptions>,
}

Specifies read preference options for non-primary read preferences.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

tag_sets: Option<Vec<TagSet>>

Specifies which replica set members should be considered for operations. Each tag set will be checked in order until one or more servers is found with each tag in the set.

max_staleness: Option<Duration>

Specifies the maximum amount of lag behind the primary that a secondary can be to be considered for the given operation. Any secondaries lagging behind more than max_staleness will not be considered for the operation.

max_staleness must be at least 90 seconds. If a max_staleness less than 90 seconds is specified for an operation, the operation will return an error.

hedge: Option<HedgedReadOptions>

Specifies hedging behavior for reads. These options only apply to sharded clusters on servers that are at least version 4.4. Note that hedged reads are automatically enabled for read preference mode “nearest”.

See the MongoDB docs for more details.

Implementations

impl ReadPreferenceOptions

pub fn builder() -> ReadPreferenceOptionsBuilder<((), (), ())>

Create a builder for building ReadPreferenceOptions. On the builder, call .tag_sets(...)(optional), .max_staleness(...)(optional), .hedge(...)(optional) to set the values of the fields. Finally, call .build() to create the instance of ReadPreferenceOptions.

Trait Implementations

impl Clone for ReadPreferenceOptions

fn clone(&self) -> ReadPreferenceOptions

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ReadPreferenceOptions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ReadPreferenceOptions

fn default() -> ReadPreferenceOptions

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for ReadPreferenceOptions

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for ReadPreferenceOptions

fn eq(&self, other: &ReadPreferenceOptions) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for ReadPreferenceOptions

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ReadPreferenceOptions