Enum DigestItem 

pub enum DigestItem {
    PreRuntime([u8; 4], Vec<u8>),
    Consensus([u8; 4], Vec<u8>),
    Seal([u8; 4], Vec<u8>),
    Other(Vec<u8>),
    RuntimeEnvironmentUpdated,
}

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

Variants

PreRuntime([u8; 4], 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([u8; 4], 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([u8; 4], Vec<u8>)

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

Other(Vec<u8>)

Some other thing. Unsupported and experimental.

RuntimeEnvironmentUpdated

An indication for the light clients that the runtime execution environment is updated.

Currently this is triggered when:

1. Runtime code blob is changed or
2. heap_pages value is changed.

Trait Implementations

impl Clone for DigestItem

fn clone(&self) -> DigestItem

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DigestItem

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

Formats the value using the given formatter.

impl Decode for DigestItem

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

where I: Input,

Attempt to deserialise the value from input.

fn decode_into<I>( input: &mut I, dst: &mut MaybeUninit<Self>, ) -> Result<DecodeFinished, Error>

where I: Input,

Attempt to deserialize the value from input into a pre-allocated piece of memory.

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> Deserialize<'a> for DigestItem

fn deserialize<D>(de: D) -> Result<DigestItem, <D as Deserializer<'a>>::Error>

where D: Deserializer<'a>,

Deserialize this value from the given Serde deserializer.

impl Encode for DigestItem

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 PartialEq for DigestItem

fn eq(&self, other: &DigestItem) -> 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 Serialize for DigestItem

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

where S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for DigestItem

impl StructuralPartialEq for DigestItem