Struct KeyValue

pub struct KeyValue<K, V> { /* private fields */ }

Key Value Database

Definition:

A key-value database, or key-value store, is a data storage paradigm designed for storing, retrieving, and managing associative arrays, and a data structure more commonly known today as a dictionary or hash table. Dictionaries contain a collection of objects, or records, which in turn have many different fields within them, each containing data. These records are stored and retrieved using a key that uniquely identifies the record, and is used to find the data within the database.

– Wikipedia

Keys and Values can be arbitrary data types, as long as they can be serialized to bincode via serde. using #[derive(Serialize, Deserialize)] on your structs should suffice. Keys must implement the Eq and Hash trait.

Examples

// any datatype that can be serialized by serde works
use serde::{Deserialize, Serialize};

#[derive(Serialize, Deserialize, Debug)]
struct Value {
    num: i32,
}

// create a new db
let mut kv = wired::KeyValue::<String, Value>::new(file)?;

// insert an item
let key = String::from("some identifier");
let value = Value { num: 42 };
kv.set(key, value);

// retrieve an item
let key = String::from("some identifier");
let value = kv.get(&key)?; // Some(Value { num: 42 })

// delete an item
let key = String::from("some identifier");
kv.remove(&key)?;

Implementations

impl<K, V> KeyValue<K, V>

where for<'de> K: Serialize + Hash + Eq + Deserialize<'de>, for<'de> V: Serialize + Deserialize<'de>,

pub fn new(file: File) -> Result<Self, Box<dyn Error>>

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn keys(&self) -> Vec<&K>

pub fn get(&self, key: &K) -> Result<Option<V>, Box<dyn Error>>

pub fn set(&mut self, key: K, value: V) -> Result<(), Box<dyn Error>>

pub fn remove(&mut self, key: &K) -> Result<(), Box<dyn Error>>