Enum Keys 

pub enum Keys {
    One(String),
    Several(Vec<String>),
    Prefix(String),
}

What a source reads: one key, several named keys, or a prefix.

Every constructor takes one, and a bare &str or String is Keys::one — so the single-key spelling every caller already wrote keeps working unchanged.

Variants

One(String)

One key, whose value is the whole document.

Several(Vec<String>)

Several named keys, merged in the order given — later wins.

The rule a list of .file(..) calls already teaches: the caller wrote the list, so the list is the precedence. One MGET, so Redis reads the set as one operation — which is also what makes this the one multi-key shape Redis::watch accepts.

Prefix(String)

Every key under a literal prefix, merged as disjoint sections.

A caller naming a prefix is not expressing an order — SCAN returns keys in whatever order the hash table is walked in — so two keys under it supplying the same path is a deployment bug, and reported as one rather than resolved.

SCAN, never KEYS: KEYS blocks the server for the length of the whole key space. The price is that the scan is not atomic, and that price is also why a prefix cannot be watched: re-finding the keys after a notification is a cursor walked over many commands, so the set it collects can be half from before a write and half from after — a document the server never held. MGET on a named list has no such window.

Implementations

impl Keys

pub fn one(key: impl Into<String>) -> Self

One key, whose value is the whole document.

pub fn several<I, S>(keys: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Several named keys, merged in the order given — later wins.

pub fn prefix(prefix: impl Into<String>) -> Self

Every key under prefix, merged as disjoint sections.

Trait Implementations

impl Clone for Keys

fn clone(&self) -> Keys

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Keys

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

Formats the value using the given formatter.

impl Eq for Keys

impl From<&String> for Keys

fn from(key: &String) -> Self

Converts to this type from the input type.

impl From<&str> for Keys

fn from(key: &str) -> Self

Converts to this type from the input type.

impl From<String> for Keys

fn from(key: String) -> Self

Converts to this type from the input type.

impl PartialEq for Keys

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Keys