pub trait Externalities: ExtensionStore {
Show 31 methods fn set_offchain_storage(&mut self, key: &[u8], value: Option<&[u8]>);
fn storage(&self, key: &[u8]) -> Option<Vec<u8>>;
fn storage_hash(&self, key: &[u8]) -> Option<Vec<u8>>;
fn child_storage_hash(
        &self,
        child_info: &ChildInfo,
        key: &[u8]
    ) -> Option<Vec<u8>>;
fn child_storage(
        &self,
        child_info: &ChildInfo,
        key: &[u8]
    ) -> Option<Vec<u8>>;
fn next_storage_key(&self, key: &[u8]) -> Option<Vec<u8>>;
fn next_child_storage_key(
        &self,
        child_info: &ChildInfo,
        key: &[u8]
    ) -> Option<Vec<u8>>;
fn kill_child_storage(
        &mut self,
        child_info: &ChildInfo,
        limit: Option<u32>
    ) -> bool;
fn clear_prefix(&mut self, prefix: &[u8]);
fn clear_child_prefix(&mut self, child_info: &ChildInfo, prefix: &[u8]);
fn place_storage(&mut self, key: Vec<u8>, value: Option<Vec<u8>>);
fn place_child_storage(
        &mut self,
        child_info: &ChildInfo,
        key: Vec<u8>,
        value: Option<Vec<u8>>
    );
fn storage_root(&mut self) -> Vec<u8>Notable traits for Vec<u8, A>impl<A> Write for Vec<u8, A> where
    A: Allocator
;
fn child_storage_root(&mut self, child_info: &ChildInfo) -> Vec<u8>Notable traits for Vec<u8, A>impl<A> Write for Vec<u8, A> where
    A: Allocator
;
fn storage_append(&mut self, key: Vec<u8>, value: Vec<u8>);
fn storage_changes_root(
        &mut self,
        parent: &[u8]
    ) -> Result<Option<Vec<u8>>, ()>;
fn storage_start_transaction(&mut self);
fn storage_rollback_transaction(&mut self) -> Result<(), ()>;
fn storage_commit_transaction(&mut self) -> Result<(), ()>;
fn wipe(&mut self);
fn commit(&mut self);
fn read_write_count(&self) -> (u32, u32, u32, u32);
fn reset_read_write_count(&mut self);
fn get_whitelist(&self) -> Vec<TrackedStorageKey>Notable traits for Vec<u8, A>impl<A> Write for Vec<u8, A> where
    A: Allocator
;
fn set_whitelist(&mut self, new: Vec<TrackedStorageKey>); fn set_storage(&mut self, key: Vec<u8>, value: Vec<u8>) { ... }
fn set_child_storage(
        &mut self,
        child_info: &ChildInfo,
        key: Vec<u8>,
        value: Vec<u8>
    ) { ... }
fn clear_storage(&mut self, key: &[u8]) { ... }
fn clear_child_storage(&mut self, child_info: &ChildInfo, key: &[u8]) { ... }
fn exists_storage(&self, key: &[u8]) -> bool { ... }
fn exists_child_storage(&self, child_info: &ChildInfo, key: &[u8]) -> bool { ... }
}
Expand description

The Substrate externalities.

Provides access to the storage and to other registered extensions.

Required methods

Write a key value pair to the offchain storage database.

Read runtime storage.

Get storage value hash.

This may be optimized for large values.

Get child storage value hash.

This may be optimized for large values.

Returns an Option that holds the SCALE encoded hash.

Read child runtime storage.

Returns an Option that holds the SCALE encoded hash.

Returns the key immediately following the given key, if it exists.

Returns the key immediately following the given key, if it exists, in child storage.

Clear an entire child storage.

Deletes all keys from the overlay and up to limit keys from the backend. No limit is applied if limit is None. Returns true if the child trie was removed completely and false if there are remaining keys after the function returns.

Note

An implementation is free to delete more keys than the specified limit as long as it is able to do that in constant time.

Clear storage entries which keys are start with the given prefix.

Clear child storage entries which keys are start with the given prefix.

Set or clear a storage entry (key) of current contract being called (effective immediately).

Set or clear a child storage entry.

Get the trie root of the current storage map.

This will also update all child storage keys in the top-level storage map.

The returned hash is defined by the Block and is SCALE encoded.

Get the trie root of a child storage map.

This will also update the value of the child storage keys in the top-level storage map.

If the storage root equals the default hash as defined by the trie, the key in the top-level storage map will be removed.

Append storage item.

This assumes specific format of the storage item. Also there is no way to undo this operation.

Get the changes trie root of the current storage overlay at a block with given parent.

parent expects a SCALE encoded hash.

The returned hash is defined by the Block and is SCALE encoded.

Start a new nested transaction.

This allows to either commit or roll back all changes made after this call to the top changes or the default child changes. For every transaction there cam be a matching call to either storage_rollback_transaction or storage_commit_transaction. Any transactions that are still open after returning from runtime are committed automatically.

Changes made without any open transaction are committed immediately.

Rollback the last transaction started by storage_start_transaction.

Any changes made during that storage transaction are discarded. Returns an error when no transaction is open that can be closed.

Commit the last transaction started by storage_start_transaction.

Any changes made during that storage transaction are committed. Returns an error when no transaction is open that can be closed.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Wipes all changes from caches and the database.

The state will be reset to genesis.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Commits all changes to the database and clears all caches.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Gets the current read/write count for the benchmarking process.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Resets read/write count for the benchmarking process.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Gets the current DB tracking whitelist.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Benchmarking related functionality and shouldn’t be used anywhere else! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Adds new storage keys to the DB tracking whitelist.

Provided methods

Set storage entry key of current contract being called (effective immediately).

Set child storage entry key of current contract being called (effective immediately).

Clear a storage entry (key) of current contract being called (effective immediately).

Clear a child storage entry (key) of current contract being called (effective immediately).

Whether a storage entry exists.

Whether a child storage entry exists.

Trait Implementations

Tries to find a registered extension and returns a mutable reference.

Register extension ext. Read more

Deregister and drop extension of T type. Read more

Implementors