Struct fedimint_core::db::Database

pub struct Database { /* private fields */ }

A public-facing newtype over IDatabase

Notably carries set of module decoders (ModuleDecoderRegistry) and implements common utility function for auto-commits, db isolation, and other.

Implementations

impl Database

pub fn new( raw: impl IRawDatabase + 'static, module_decoders: ModuleDecoderRegistry ) -> Self

Creates a new Fedimint database from any object implementing IDatabase.

See also Database::new_from_arc.

pub fn new_from_arc( inner: Arc<dyn IDatabase + 'static>, module_decoders: ModuleDecoderRegistry ) -> Self

Create Database from an already typed-erased IDatabase.

pub fn with_prefix(&self, prefix: Vec<u8>) -> Self

Create Database isolated to a partition with a given prefix

pub fn with_prefix_module_id( &self, module_instance_id: ModuleInstanceId ) -> Self

Create Database isolated to a partition with a prefix for a given module_instance_id

pub fn with_decoders(&self, module_decoders: ModuleDecoderRegistry) -> Self

pub fn is_global(&self) -> bool

Is this Database a global, unpartitioned Database

pub fn ensure_global(&self) -> Result<()>

Err if Self::is_global is not true

pub fn ensure_isolated(&self) -> Result<()>

Err if Self::is_global is true

pub async fn begin_transaction<'s, 'tx>( &'s self ) -> DatabaseTransaction<'tx, Committable>where 's: 'tx,

Begin a new committable database transaction

pub async fn begin_transaction_nc<'s, 'tx>( &'s self ) -> DatabaseTransaction<'tx, NonCommittable>where 's: 'tx,

Begin a new non-committable database transaction

pub async fn autocommit<'s, 'dbtx, F, T, E>( &'s self, tx_fn: F, max_attempts: Option<usize> ) -> Result<T, AutocommitError<E>>where for<'r, 'o> F: Fn(&'r mut DatabaseTransaction<'o>, PhantomBound<'dbtx, 'o>) -> BoxFuture<'r, Result<T, E>>, 's: 'dbtx,

Runs a closure with a reference to a database transaction and tries to commit the transaction if the closure returns Ok and rolls it back otherwise. If committing fails the closure is run for up to max_attempts times. If max_attempts is None it will run usize::MAX times which is close enough to infinite times.

The closure tx_fn provided should not have side effects outside of the database transaction provided, or if it does these should be idempotent, since the closure might be run multiple times.

Lifetime Parameters

The higher rank trait bound (HRTB) 'a that is applied to the the mutable reference to the database transaction ensures that the reference lives as least as long as the returned future of the closure.

Further, the reference to self ('s) must outlive the DatabaseTransaction<'dt>. In other words, the DatabaseTransaction must live as least as long as self and that is true as the DatabaseTransaction is only dropped at the end of the loop{}.

Panics

This function panics when the given number of maximum attempts is zero. max_attempts must be greater or equal to one.

pub async fn wait_key_check<'a, K, T>( &'a self, key: &K, checker: impl Fn(Option<K::Value>) -> Option<T> ) -> (T, DatabaseTransaction<'a, Committable>)where K: DatabaseKey + DatabaseRecord + DatabaseKeyWithNotify,

Waits for key to be notified.

Calls the checker when value of the key may have changed. Returns the value when checker returns a Some(T).

pub async fn wait_key_exists<K>(&self, key: &K) -> K::Valuewhere K: DatabaseKey + DatabaseRecord + DatabaseKeyWithNotify,

Waits for key to be present in database.

Trait Implementations

impl Clone for Database

fn clone(&self) -> Database

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Database

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

Formats the value using the given formatter.

impl<T> From<T> for Databasewhere T: IRawDatabase,

fn from(raw: T) -> Self

Converts to this type from the input type.