Enum polkadot_node_subsystem_types::messages::ChainApiMessage

pub enum ChainApiMessage {
    BlockNumber(Hash, ChainApiResponseChannel<Option<BlockNumber>>),
    BlockHeader(Hash, ChainApiResponseChannel<Option<Header>>),
    BlockWeight(Hash, ChainApiResponseChannel<Option<BlockWeight>>),
    FinalizedBlockHash(BlockNumber, ChainApiResponseChannel<Option<Hash>>),
    FinalizedBlockNumber(ChainApiResponseChannel<BlockNumber>),
    Ancestors {
        hash: Hash,
        k: usize,
        response_channel: ChainApiResponseChannel<Vec<Hash>>,
    },
}

Chain API request subsystem message.

Variants

BlockNumber(Hash, ChainApiResponseChannel<Option<BlockNumber>>)

Request the block number by hash. Returns None if a block with the given hash is not present in the db.

BlockHeader(Hash, ChainApiResponseChannel<Option<Header>>)

Request the block header by hash. Returns None if a block with the given hash is not present in the db.

BlockWeight(Hash, ChainApiResponseChannel<Option<BlockWeight>>)

Get the cumulative weight of the given block, by hash. If the block or weight is unknown, this returns None.

Note: this is the weight within the low-level fork-choice rule, not the high-level one implemented in the chain-selection subsystem.

Weight is used for comparing blocks in a fork-choice rule.

FinalizedBlockHash(BlockNumber, ChainApiResponseChannel<Option<Hash>>)

Request the finalized block hash by number. Returns None if a block with the given number is not present in the db. Note: the caller must ensure the block is finalized.

FinalizedBlockNumber(ChainApiResponseChannel<BlockNumber>)

Request the last finalized block number. This request always succeeds.

Ancestors

Request the k ancestor block hashes of a block with the given hash. The response channel may return a Vec of size up to k filled with ancestors hashes with the following order: parent, grandparent, … up to the hash of genesis block with number 0, including it.

Fields

hash: Hash

The hash of the block in question.

k: usize

The number of ancestors to request.

response_channel: ChainApiResponseChannel<Vec<Hash>>

The response channel.

Trait Implementations

impl Debug for ChainApiMessage

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

Formats the value using the given formatter.