Struct cumulus_primitives_parachain_inherent::MessageQueueChain

pub struct MessageQueueChain(/* private fields */);

This struct provides ability to extend a message queue chain (MQC) and compute a new head.

MQC is an instance of a hash chain applied to a message queue. Using a hash chain it’s possible to represent a sequence of messages using only a single hash.

A head for an empty chain is agreed to be a zero hash.

An instance is used to track either DMP from the relay chain or HRMP across a channel. But a given instance is never used to track both. Therefore, you should call either extend_downward or extend_hrmp, but not both methods on a single instance.

Implementations

impl MessageQueueChain

pub fn new(hash: RelayHash) -> Self

Create a new instance initialized to hash.

pub fn extend_hrmp( &mut self, horizontal_message: &InboundHrmpMessage, ) -> &mut Self

Extend the hash chain with an HRMP message. This method should be used only when this chain is tracking HRMP.

pub fn extend_downward( &mut self, downward_message: &InboundDownwardMessage, ) -> &mut Self

Extend the hash chain with a downward message. This method should be used only when this chain is tracking DMP.

pub fn head(&self) -> RelayHash

Return the current mead of the message queue hash chain. This is agreed to be the zero hash for an empty chain.

Trait Implementations

impl Clone for MessageQueueChain

fn clone(&self) -> MessageQueueChain

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Decode for MessageQueueChain

fn decode<__CodecInputEdqy: Input>( __codec_input_edqy: &mut __CodecInputEdqy, ) -> Result<Self, Error>

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 Default for MessageQueueChain

fn default() -> MessageQueueChain

Returns the “default value” for a type.

impl Encode for MessageQueueChain

fn size_hint(&self) -> usize

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

fn encode_to<__CodecOutputEdqy: Output + ?Sized>( &self, __codec_dest_edqy: &mut __CodecOutputEdqy, )

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

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

Convert self to an owned vector.

fn using_encoded<__CodecOutputReturn, __CodecUsingEncodedCallback: FnOnce(&[u8]) -> __CodecOutputReturn>( &self, f: __CodecUsingEncodedCallback, ) -> __CodecOutputReturn

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

fn encoded_size(&self) -> usize

Calculates the encoded size.

impl TypeInfo for MessageQueueChain

type Identity = MessageQueueChain

The type identifying for which type info is provided.

fn type_info() -> Type

Returns the static type identifier for Self.

impl EncodeLike for MessageQueueChain