Enum DigestItem

pub enum DigestItem<Hash> {
    ChangesTrieRoot(Hash),
    PreRuntime(ConsensusEngineId, Vec<u8>),
    Consensus(ConsensusEngineId, Vec<u8>),
    Seal(ConsensusEngineId, Vec<u8>),
    ChangesTrieSignal(ChangesTrieSignal),
    Other(Vec<u8>),
}

Digest item that is able to encode/decode ‘system’ digest items and provide opaque access to other items.

Variants

ChangesTrieRoot(Hash)

System digest item that contains the root of changes trie at given block. It is created for every block iff runtime supports changes trie creation.

PreRuntime(ConsensusEngineId, Vec<u8>)

A pre-runtime digest.

These are messages from the consensus engine to the runtime, although the consensus engine can (and should) read them itself to avoid code and state duplication. It is erroneous for a runtime to produce these, but this is not (yet) checked.

NOTE: the runtime is not allowed to panic or fail in an on_initialize call if an expected PreRuntime digest is not present. It is the responsibility of a external block verifier to check this. Runtime API calls will initialize the block without pre-runtime digests, so initialization cannot fail when they are missing.

Consensus(ConsensusEngineId, Vec<u8>)

A message from the runtime to the consensus engine. This should never be generated by the native code of any consensus engine, but this is not checked (yet).

Seal(ConsensusEngineId, Vec<u8>)

Put a Seal on it. This is only used by native code, and is never seen by runtimes.

ChangesTrieSignal(ChangesTrieSignal)

Digest item that contains signal from changes tries manager to the native code.

Other(Vec<u8>)

Some other thing. Unsupported and experimental.

Implementations

impl<Hash> DigestItem<Hash>

pub fn dref<'a>(&'a self) -> DigestItemRef<'a, Hash>

Returns a ‘referencing view’ for this digest item.

pub fn as_changes_trie_root(&self) -> Option<&Hash>

Returns Some if the entry is the ChangesTrieRoot entry.

pub fn as_pre_runtime(&self) -> Option<(ConsensusEngineId, &[u8])>

Returns Some if this entry is the PreRuntime entry.

pub fn as_consensus(&self) -> Option<(ConsensusEngineId, &[u8])>

Returns Some if this entry is the Consensus entry.

pub fn as_seal(&self) -> Option<(ConsensusEngineId, &[u8])>

Returns Some if this entry is the Seal entry.

pub fn as_changes_trie_signal(&self) -> Option<&ChangesTrieSignal>

Returns Some if the entry is the ChangesTrieSignal entry.

pub fn as_other(&self) -> Option<&[u8]>

Returns Some if self is a DigestItem::Other.

pub fn try_as_raw(&self, id: OpaqueDigestItemId<'_>) -> Option<&[u8]>

Returns the opaque data contained in the item if Some if this entry has the id given.

pub fn try_to<T: Decode>(&self, id: OpaqueDigestItemId<'_>) -> Option<T>

Returns the data contained in the item if Some if this entry has the id given, decoded to the type provided T.

Trait Implementations

impl<H> CheckEqual for DigestItem<H>

where H: Encode + PartialEq + Eq + Debug,

fn check_equal(&self, other: &Self)

Perform the equality check.

impl<Hash: Clone> Clone for DigestItem<Hash>

fn clone(&self) -> DigestItem<Hash>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<Hash> Debug for DigestItem<Hash>

where Hash: Debug,

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

Formats the value using the given formatter.

impl<Hash: Decode> Decode for DigestItem<Hash>

fn decode<I: Input>(input: &mut I) -> Result<Self, Error>

Attempt to deserialise the value from input.

fn skip<I>(input: &mut I) -> Result<(), Error>

where I: Input,

Attempt to skip the encoded value from input.

fn encoded_fixed_size() -> Option<usize>

Returns the fixed encoded size of the type.

impl<'a, Hash: Decode> Deserialize<'a> for DigestItem<Hash>

fn deserialize<D>(de: D) -> Result<Self, D::Error>

where D: Deserializer<'a>,

Deserialize this value from the given Serde deserializer.

impl<Hash: Encode> Encode for DigestItem<Hash>

fn encode(&self) -> Vec<u8>

Convert self to an owned vector.

fn size_hint(&self) -> usize

If possible give a hint of expected size of the encoding.

fn encode_to<T>(&self, dest: &mut T)

where T: Output + ?Sized,

Convert self to a slice and append it to the destination.

fn using_encoded<R, F>(&self, f: F) -> R

where F: FnOnce(&[u8]) -> R,

Convert self to a slice and then invoke the given closure with it.

fn encoded_size(&self) -> usize

Calculates the encoded size.

impl<Hash> MallocSizeOf for DigestItem<Hash>

where Hash: MallocSizeOf,

fn size_of(&self, ops: &mut MallocSizeOfOps) -> usize

Measure the heap usage of all descendant heap-allocated structures, but not the space taken up by the value itself. If T::size_of is a constant, consider implementing constant_size as well.

fn constant_size() -> Option<usize>

where Self: Sized,

Used to optimize MallocSizeOf implementation for collections like Vec and HashMap to avoid iterating over them unnecessarily. The Self: Sized bound is for object safety.

impl<Hash: PartialEq> PartialEq for DigestItem<Hash>

fn eq(&self, other: &DigestItem<Hash>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<Hash: Encode> Serialize for DigestItem<Hash>

fn serialize<S>(&self, seq: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<Hash: Encode> EncodeLike for DigestItem<Hash>

impl<Hash: Eq> Eq for DigestItem<Hash>

impl<Hash> StructuralPartialEq for DigestItem<Hash>