Struct MetaKvBackend

pub struct MetaKvBackend {
    pub client: Arc<MetaClient>,
}

Fields

client: Arc<MetaClient>

Implementations

impl MetaKvBackend

pub fn new(client: Arc<MetaClient>) -> MetaKvBackend

Constructs a MetaKvBackend.

Trait Implementations

impl Debug for MetaKvBackend

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

Formats the value using the given formatter.

impl KvBackend for MetaKvBackend

Implement KvBackend trait for MetaKvBackend instead of opendal’s Accessor since MetaClient’s range method can return both keys and values, which can reduce IO overhead comparing to Accessor’s list and get method.

fn name(&self) -> &str

fn as_any(&self) -> &dyn Any

fn range<'life0, 'async_trait>( &'life0 self, req: RangeRequest, ) -> Pin<Box<dyn Future<Output = Result<RangeResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

fn put<'life0, 'async_trait>( &'life0 self, req: PutRequest, ) -> Pin<Box<dyn Future<Output = Result<PutResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

fn batch_put<'life0, 'async_trait>( &'life0 self, req: BatchPutRequest, ) -> Pin<Box<dyn Future<Output = Result<BatchPutResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

fn batch_get<'life0, 'async_trait>( &'life0 self, req: BatchGetRequest, ) -> Pin<Box<dyn Future<Output = Result<BatchGetResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

fn compare_and_put<'life0, 'async_trait>( &'life0 self, request: CompareAndPutRequest, ) -> Pin<Box<dyn Future<Output = Result<CompareAndPutResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

CAS: Compares the value at the key with the given value, and if they are equal, puts the new value at the key.

fn delete_range<'life0, 'async_trait>( &'life0 self, req: DeleteRangeRequest, ) -> Pin<Box<dyn Future<Output = Result<DeleteRangeResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

fn batch_delete<'life0, 'async_trait>( &'life0 self, req: BatchDeleteRequest, ) -> Pin<Box<dyn Future<Output = Result<BatchDeleteResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

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

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

fn put_conditionally<'life0, 'async_trait>( &'life0 self, key: Vec<u8>, value: Vec<u8>, if_not_exists: bool, ) -> Pin<Box<dyn Future<Output = Result<bool, Self::Error>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: Sync + 'async_trait,

Puts a value at a key. If if_not_exists is true, the operation ensures the key does not exist before applying the PUT operation. Otherwise, it simply applies the PUT operation without checking for the key’s existence.

fn exists<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 [u8], ) -> Pin<Box<dyn Future<Output = Result<bool, Self::Error>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, Self: Sync + 'async_trait,

Check if the key exists, not returning the value. If the value is large, this method is more efficient than get.

fn delete<'life0, 'life1, 'async_trait>( &'life0 self, key: &'life1 [u8], prev_kv: bool, ) -> Pin<Box<dyn Future<Output = Result<Option<KeyValue>, Self::Error>> + Send + 'async_trait>>

where 'life0: 'async_trait, 'life1: 'async_trait, Self: Sync + 'async_trait,

Returns previous key-value pair if prev_kv is true.

impl TxnService for MetaKvBackend

type Error = Error

fn txn<'life0, 'async_trait>( &'life0 self, _txn: Txn, ) -> Pin<Box<dyn Future<Output = Result<TxnResponse, Self::Error>> + Send + 'async_trait>>

where 'life0: 'async_trait, Self: 'async_trait,

fn max_txn_ops(&self) -> usize

Maximum number of operations permitted in a transaction.