Enum Request

pub enum Request {
    Echo(Echo),
    Flush,
    Info(Info),
    SetOption(SetOption),
    InitChain(InitChain),
    Query(Query),
    BeginBlock(BeginBlock),
    CheckTx(CheckTx),
    DeliverTx(DeliverTx),
    EndBlock(EndBlock),
    Commit,
    ListSnapshots,
    OfferSnapshot(OfferSnapshot),
    LoadSnapshotChunk(LoadSnapshotChunk),
    ApplySnapshotChunk(ApplySnapshotChunk),
}

All possible ABCI requests in CometBFT 0.34.

Variants

Echo(Echo)

Echoes a string to test an ABCI implementation.

ABCI documentation

Flush

Indicates that any pending requests should be completed and their responses flushed.

ABCI documentation

Info(Info)

Requests information about the application state.

ABCI documentation

SetOption(SetOption)

Undocumented, non-deterministic, was removed from Tendermint in 0.35.

InitChain(InitChain)

Called on genesis to initialize chain state.

ABCI documentation

Query(Query)

Queries for data from the application at current or past height.

ABCI documentation

BeginBlock(BeginBlock)

Signals the beginning of a new block.

Called prior to any DeliverTxs. The header contains the height, timestamp, and more – it exactly matches the Tendermint block header.

ABCI documentation

CheckTx(CheckTx)

Check whether a transaction should be included in the mempool.

CheckTx is not involved in processing blocks, only in deciding whether a transaction should be included in the mempool. Every node runs CheckTx before adding a transaction to its local mempool. The transaction may come from an external user or another node. CheckTx need not execute the transaction in full, but can instead perform lightweight or statateful validation (e.g., checking signatures or account balances) instead of more expensive checks (like running code in a virtual machine).

ABCI documentation

DeliverTx(DeliverTx)

Execute a transaction against the application state.

ABCI documentation

EndBlock(EndBlock)

Signals the end of a block.

Called after all transactions, and prior to each Commit.

ABCI documentation

Commit

Signals the application that it can write the queued state transitions from the block to its state.

ABCI documentation

ListSnapshots

Asks the application for a list of snapshots.

ABCI documentation

OfferSnapshot(OfferSnapshot)

Offers a list of snapshots to the application.

OfferSnapshot is called when bootstrapping a node using state sync. The application may accept or reject snapshots as appropriate. Upon accepting, Tendermint will retrieve and apply snapshot chunks via ApplySnapshotChunk. The application may also choose to reject a snapshot in the chunk response, in which case it should be prepared to accept further OfferSnapshot calls.

Only app_hash can be trusted, as it has been verified by the light client. Any other data can be spoofed by adversaries, so applications should employ additional verification schemes to avoid denial-of-service attacks. The verified app_hash is automatically checked against the restored application at the end of snapshot restoration.

See also the Snapshot data type and the ABCI state sync documentation.

ABCI documentation

LoadSnapshotChunk(LoadSnapshotChunk)

Used during state sync to retrieve snapshot chunks from peers.

ABCI documentation

ApplySnapshotChunk(ApplySnapshotChunk)

Applies a snapshot chunk.

The application can choose to refetch chunks and/or ban P2P peers as appropriate. Tendermint will not do this unless instructed by the application.

The application may want to verify each chunk, e.g., by attaching chunk hashes in Snapshot::metadata and/or incrementally verifying contents against app_hash.

When all chunks have been accepted, Tendermint will make an ABCI Info request to verify that last_block_app_hash and last_block_height match the expected values, and record the app_version in the node state. It then switches to fast sync or consensus and joins the network.

If Tendermint is unable to retrieve the next chunk after some time (e.g., because no suitable peers are available), it will reject the snapshot and try a different one via OfferSnapshot. The application should be prepared to reset and accept it or abort as appropriate.

ABCI documentation

Implementations

impl Request

pub fn kind(&self) -> MethodKind

Get the method kind for this request.

Trait Implementations

impl Clone for Request

fn clone(&self) -> Request

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Request

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

Formats the value using the given formatter.

impl From<ConsensusRequest> for Request

fn from(req: ConsensusRequest) -> Self

Converts to this type from the input type.

impl From<InfoRequest> for Request

fn from(req: InfoRequest) -> Self

Converts to this type from the input type.

impl From<MempoolRequest> for Request

fn from(req: MempoolRequest) -> Self

Converts to this type from the input type.

impl From<Request> for Request

fn from(request: Request) -> Request

Converts to this type from the input type.

impl From<SnapshotRequest> for Request

fn from(req: SnapshotRequest) -> Self

Converts to this type from the input type.

impl PartialEq for Request

fn eq(&self, other: &Request) -> 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 Protobuf<Request> for Request

fn encode<B>(self, buf: &mut B) -> Result<(), Error>

where B: BufMut,

Encode into a buffer in Protobuf format.

fn encode_length_delimited<B>(self, buf: &mut B) -> Result<(), Error>

where B: BufMut,

Encode with a length-delimiter to a buffer in Protobuf format.

fn decode<B>(buf: B) -> Result<Self, Error>

where B: Buf,

Constructor that attempts to decode an instance from a buffer.

fn decode_length_delimited<B>(buf: B) -> Result<Self, Error>

where B: Buf,

Constructor that attempts to decode a length-delimited instance from the buffer.

fn encoded_len(self) -> usize

Returns the encoded length of the message without a length delimiter.

fn encode_vec(self) -> Vec<u8>

Encodes into a Protobuf-encoded Vec<u8>.

fn decode_vec(v: &[u8]) -> Result<Self, Error>

Constructor that attempts to decode a Protobuf-encoded instance from a Vec<u8> (or equivalent).

fn encode_length_delimited_vec(self) -> Vec<u8>

Encode with a length-delimiter to a Vec<u8> Protobuf-encoded message.

fn decode_length_delimited_vec(v: &[u8]) -> Result<Self, Error>

Constructor that attempts to decode a Protobuf-encoded instance with a length-delimiter from a Vec<u8> or equivalent.

impl TryFrom<Request> for ConsensusRequest

type Error = Error

The type returned in the event of a conversion error.

fn try_from(req: Request) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Request> for InfoRequest

type Error = Error

The type returned in the event of a conversion error.

fn try_from(req: Request) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Request> for MempoolRequest

type Error = Error

The type returned in the event of a conversion error.

fn try_from(req: Request) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Request> for Request

type Error = Error

The type returned in the event of a conversion error.

fn try_from(request: Request) -> Result<Self, Self::Error>

Performs the conversion.

impl TryFrom<Request> for SnapshotRequest

type Error = Error

The type returned in the event of a conversion error.

fn try_from(req: Request) -> Result<Self, Self::Error>

Performs the conversion.

impl Eq for Request

impl StructuralPartialEq for Request