Trait tantivy::directory::Directory [−][src]
pub trait Directory: DirectoryClone + Debug + Send + Sync + 'static { fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError>; fn delete(&self, path: &Path) -> Result<(), DeleteError>; fn exists(&self, path: &Path) -> bool; fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError>; fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>; fn atomic_write(&mut self, path: &Path, data: &[u8]) -> Result<()>; }
Write-once read many (WORM) abstraction for where tantivy's data should be stored.
There are currently two implementations of Directory
- The
MMapDirectory
, this should be your default choice. - The
RAMDirectory
, which should be used mostly for tests.
Required Methods
fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError>
Opens a virtual file for read.
Once a virtual file is open, its data may not change.
Specifically, subsequent writes or flushes should
have no effect on the returned ReadOnlySource
object.
fn delete(&self, path: &Path) -> Result<(), DeleteError>
Removes a file
Removing a file will not affect an eventual existing ReadOnlySource pointing to it.
Removing a nonexistent file, yields a
DeleteError::DoesNotExist
.
fn exists(&self, path: &Path) -> bool
Returns true iff the file exists
fn open_write(&mut self, path: &Path) -> Result<WritePtr, OpenWriteError>
Opens a writer for the virtual file associated with a Path.
Right after this call, the file should be created
and any subsequent call to open_read
for the
same path should return a ReadOnlySource
.
Write operations may be aggressively buffered.
The client of this trait is responsible for calling flush
to ensure that subsequent read
operations
will take into account preceding write
operations.
Flush operation should also be persistent.
The user shall not rely on Drop
triggering flush
.
Note that RAMDirectory
will panic! if flush
was not called.
The file may not previously exist.
fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError>
Reads the full content file that has been written using atomic_write.
This should only be used for small files.
fn atomic_write(&mut self, path: &Path, data: &[u8]) -> Result<()>
Atomically replace the content of a file with data.
This calls ensure that reads can never observe a partially written file.
The file may or may not previously exist.
Implementors
impl Directory for MmapDirectory
impl Directory for RAMDirectory