Enum ShardingStrategy 

pub enum ShardingStrategy {
    Hash,
    Range,
    Date,
    Enum {
        mapping: HashMap<String, String>,
        default: Option<String>,
    },
    List {
        keys: HashSet<String>,
        target: String,
        default: Option<String>,
    },
    Directory {
        table: HashMap<String, String>,
    },
    Composite {
        primary: Box<ShardingStrategy>,
        primary_shards: Vec<String>,
        secondary: Box<ShardingStrategy>,
        secondary_shards: Vec<String>,
    },
}

Sharding strategy.

Note: from v0.3.0 this is extended to a non-Copy enum (with new Enum/List/Directory/Composite variants that carry data). The routing behavior of the three original variants Hash/Range/Date remains backward compatible.

Variants

Hash

Hash sharding: hash the key and select a shard by modulo.

Range

Range sharding: select a shard by the byte-value range of the key.

Date

Date sharding: select a shard by the date information (YYYY-MM-DD) in the key.

Enum

Enum sharding: explicit key → shard mapping; unmatched keys go to the default shard.

Fields

mapping: HashMap<String, String>

Explicit mapping table.

default: Option<String>

Default shard when no match.

List

List sharding: route to target if the key is in the predefined set, otherwise default.

Fields

keys: HashSet<String>

Predefined key set.

target: String

Target shard on hit.

default: Option<String>

Default shard on miss.

Directory

Directory sharding: dynamically query a routing table (key → shard).

Fields

table: HashMap<String, String>

Dynamic routing table.

Composite

Composite sharding: first route by primary to obtain a group, then route “group:key” with secondary for the second-level routing.

Fields

primary: Box<ShardingStrategy>

Primary strategy (decides the group).

primary_shards: Vec<String>

Shard list used by the primary strategy (i.e. the set of group labels).

secondary: Box<ShardingStrategy>

Secondary strategy (routes within the group).

secondary_shards: Vec<String>

Shard list used by the secondary strategy (final shard).

Trait Implementations

impl Clone for ShardingStrategy

fn clone(&self) -> ShardingStrategy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ShardingStrategy

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ShardingStrategy

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for ShardingStrategy

impl PartialEq for ShardingStrategy

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for ShardingStrategy

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 ShardingStrategy