bark::persist::adaptor

Trait StorageAdaptor

Source 
pub trait StorageAdaptor:
    Send
    + Sync
    + 'static {
    // Required methods
    fn put<'life0, 'async_trait>(
        &'life0 mut self,
        record: Record,
    ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn get<'life0, 'life1, 'async_trait>(
        &'life0 self,
        partition: u8,
        pk: &'life1 [u8],
    ) -> Pin<Box<dyn Future<Output = Result<Option<Record>>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;
    fn delete<'life0, 'life1, 'async_trait>(
        &'life0 mut self,
        partition: u8,
        pk: &'life1 [u8],
    ) -> Pin<Box<dyn Future<Output = Result<Option<Record>>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;
    fn query<'life0, 'async_trait>(
        &'life0 self,
        query: Query,
    ) -> Pin<Box<dyn Future<Output = Result<Vec<Record>>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;

    // Provided method
    fn incremental_id<'life0, 'async_trait>(
        &'life0 mut self,
        partition: u8,
    ) -> Pin<Box<dyn Future<Output = Result<u32>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait { ... }
}
Expand description

Storage adaptor trait for persistence backends.

This trait provides a minimal interface (4 methods) that can be efficiently implemented on various storage backends while enabling query optimization.

§Implementor’s Guide

§Simple backends (memory, file-based)

Store records in a map/list and implement query by filtering in memory.

§Database backends (Postgres, MongoDB, Firebase, IndexedDB, etc.)

Create a single table with indexes:

CREATE TABLE storage (
    pk TEXT PRIMARY KEY,
    partition TEXT NOT NULL,
    sort_key BLOB,
    data BLOB NOT NULL
);
CREATE INDEX idx_partition_sort ON storage(partition, sort_key);

Translate Query to SQL:

SELECT * FROM storage
WHERE partition = :partition
ORDER BY :sort_key DESC

Required Methods§

Source

fn put<'life0, 'async_trait>( &'life0 mut self, record: Record, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Stores a record, inserting or updating by primary key.

Source

fn get<'life0, 'life1, 'async_trait>( &'life0 self, partition: u8, pk: &'life1 [u8], ) -> Pin<Box<dyn Future<Output = Result<Option<Record>>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Retrieves a record by primary key.

Returns None if the record doesn’t exist.

Source

fn delete<'life0, 'life1, 'async_trait>( &'life0 mut self, partition: u8, pk: &'life1 [u8], ) -> Pin<Box<dyn Future<Output = Result<Option<Record>>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Deletes a record by primary key.

Returns the deleted record if it existed, None otherwise.

Source

fn query<'life0, 'async_trait>( &'life0 self, query: Query, ) -> Pin<Box<dyn Future<Output = Result<Vec<Record>>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Queries records in a partition

Results are ordered by sort key. Records without a sort key appear last.

Provided Methods§

Source

fn incremental_id<'life0, 'async_trait>( &'life0 mut self, partition: u8, ) -> Pin<Box<dyn Future<Output = Result<u32>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Increments the last partition id, then stores and returns the new id.

Implementors§