Struct MigrationContext 

pub struct MigrationContext { /* private fields */ }

Context passed to migration functions. Provides put/get/delete against the module’s schema tree and access to the database for opening other trees.

Migrations run locally in the module process. Use put/get/delete for schema metadata. For application data migrations, use open_tree to open and migrate other trees.

Implementations

impl MigrationContext

pub fn new(tree: Arc<dyn Tree>, db: Arc<dyn Database>) -> Self

Create a new MigrationContext wrapping the schema tree and database.

pub fn put(&self, key: &[u8], value: &[u8]) -> Result<()>

Insert a key-value pair into the schema tree.

pub fn get(&self, key: &[u8]) -> Result<Option<Vec<u8>>>

Get a value by key from the schema tree.

pub fn delete(&self, key: &[u8]) -> Result<()>

Remove a key from the schema tree.

pub fn open_tree(&self, name: &str) -> Result<Box<dyn Tree>>

Open a named tree for application data migrations.

Trait Implementations

impl Clone for MigrationContext

fn clone(&self) -> MigrationContext

Returns a duplicate of the value.

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

Performs copy-assignment from source.