Struct CachedBackend

pub struct CachedBackend {
    be: Arc<dyn WriteBackend>,
    cache: Cache,
}

Backend that caches data.

This backend caches data in a directory. It can be used to cache data from a remote backend.

Type Parameters

• BE - The backend to cache.

Fields

be: Arc<dyn WriteBackend>

The backend to cache.

cache: Cache

The cache.

Implementations

impl CachedBackend

pub fn new_cache( be: Arc<dyn WriteBackend>, cache: Cache, ) -> Arc<dyn WriteBackend>

Create a new CachedBackend from a given backend.

Type Parameters

• BE - The backend to cache.

Trait Implementations

impl Clone for CachedBackend

fn clone(&self) -> CachedBackend

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for CachedBackend

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

Formats the value using the given formatter.

impl ReadBackend for CachedBackend

fn location(&self) -> String

Returns the location of the backend as a String.

fn list_with_size(&self, tpe: FileType) -> RusticResult<Vec<(Id, u32)>>

Lists all files with their size of the given type.

Arguments

• tpe - The type of the files to list.

Errors

• If the backend does not support listing files.

Returns

A vector of tuples containing the id and size of the files.

fn read_full(&self, tpe: FileType, id: &Id) -> RusticResult<Bytes>

Reads full data of the given file.

Arguments

• tpe - The type of the file.
• id - The id of the file.

Errors

• If the file could not be read.

Returns

The data read.

fn read_partial( &self, tpe: FileType, id: &Id, cacheable: bool, offset: u32, length: u32, ) -> RusticResult<Bytes>

Reads partial data of the given file.

Arguments

• tpe - The type of the file.
• id - The id of the file.
• cacheable - Whether the file is cacheable.
• offset - The offset to read from.
• length - The length to read.

Errors

• If the file could not be read.

Returns

The data read.

fn needs_warm_up(&self) -> bool

Specify if the backend needs a warming-up of files before accessing them.

fn warm_up(&self, tpe: FileType, id: &Id) -> RusticResult<()>

Warm-up the given file.

fn list(&self, tpe: FileType) -> RusticResult<Vec<Id>>

Lists all files of the given type.

impl WriteBackend for CachedBackend

fn create(&self) -> RusticResult<()>

Creates the backend.

fn write_bytes( &self, tpe: FileType, id: &Id, cacheable: bool, buf: Bytes, ) -> RusticResult<()>

Writes the given data to the given file.

If the file is cacheable, it will also be written to the cache.

Arguments

• tpe - The type of the file.
• id - The id of the file.
• cacheable - Whether the file is cacheable.
• buf - The data to write.

fn remove(&self, tpe: FileType, id: &Id, cacheable: bool) -> RusticResult<()>

Removes the given file.

If the file is cacheable, it will also be removed from the cache.

Arguments

• tpe - The type of the file.
• id - The id of the file.