Enum Consistency 

pub enum Consistency {
    None,
    One,
    Two,
    Three,
    Quorum,
    LocalQuorum,
    All,
    EachQuorum,
}

The consistency level which should be reached before a write can be returned as successful.

If the consistency level is not met then an error should be returned, but this does not mean that the operation has failed to go through on all nodes, it simply means that the target number of replicas has not been reached.

Variants

None

No other replicas will have the operation broadcast to them.

One

Broadcast the change to one replica as determined by the NodeSelector.

Two

Broadcast the change to two replicas as determined by the NodeSelector.

Three

Broadcast the change to three replicas as determined by the NodeSelector.

Quorum

A simple majority of all replicas across all data centers.

The nodes selected are determined by the node selector, this is designed to be a hint to the node selector rather than a fixed rule.

LocalQuorum

A simple majority of in the local data center.

The nodes selected are determined by the node selector, this is designed to be a hint to the node selector rather than a fixed rule.

All

The change is broadcast to all nodes as part of the cluster.

EachQuorum

A simple majority in each data center.

If no data center is provided to any nodes when they’re created, this is the same as Consistency::Quorum.

The nodes selected are determined by the node selector, this is designed to be a hint to the node selector rather than a fixed rule.

Trait Implementations

impl Clone for Consistency

fn clone(&self) -> Consistency

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Consistency

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

Formats the value using the given formatter.

impl Hash for Consistency

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for Consistency

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

Tests for self and other values to be equal, and is used by ==.

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

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

impl Copy for Consistency

impl Eq for Consistency

impl StructuralPartialEq for Consistency