Enum ReadRequest

pub enum ReadRequest {
    Tip,
    TipPoolValues,
    Depth(Hash),
    Block(HashOrHeight),
    BlockHeader(HashOrHeight),
    Transaction(Hash),
    TransactionIdsForBlock(HashOrHeight),
    UnspentBestChainUtxo(OutPoint),
    AnyChainUtxo(OutPoint),
    BlockLocator,
    FindBlockHashes {
        known_blocks: Vec<Hash>,
        stop: Option<Hash>,
    },
    FindBlockHeaders {
        known_blocks: Vec<Hash>,
        stop: Option<Hash>,
    },
    SaplingTree(HashOrHeight),
    OrchardTree(HashOrHeight),
    SaplingSubtrees {
        start_index: NoteCommitmentSubtreeIndex,
        limit: Option<NoteCommitmentSubtreeIndex>,
    },
    OrchardSubtrees {
        start_index: NoteCommitmentSubtreeIndex,
        limit: Option<NoteCommitmentSubtreeIndex>,
    },
    AddressBalance(HashSet<Address>),
    TransactionIdsByAddresses {
        addresses: HashSet<Address>,
        height_range: RangeInclusive<Height>,
    },
    UtxosByAddresses(HashSet<Address>),
    CheckBestChainTipNullifiersAndAnchors(UnminedTx),
    BestChainNextMedianTimePast,
    BestChainBlockHash(Height),
    ChainInfo,
    SolutionRate {
        num_blocks: usize,
        height: Option<Height>,
    },
    CheckBlockProposalValidity(SemanticallyVerifiedBlock),
    TipBlockSize,
}

A read-only query about the chain state, via the ReadStateService.

Variants

Tip

Returns ReadResponse::Tip(Option<(Height, block::Hash)>) with the current best chain tip.

TipPoolValues

Returns ReadResponse::TipPoolValues(Option<(Height, block::Hash, ValueBalance)>) with the current best chain tip.

Depth(Hash)

Computes the depth in the current best chain of the block identified by the given hash.

Returns

• ReadResponse::Depth(Some(depth)) if the block is in the best chain;
• ReadResponse::Depth(None) otherwise.

Block(HashOrHeight)

Looks up a block by hash or height in the current best chain.

Returns

• ReadResponse::Block(Some(Arc<Block>)) if the block is in the best chain;
• ReadResponse::Block(None) otherwise.

Note: the HashOrHeight can be constructed from a block::Hash or block::Height using .into().

BlockHeader(HashOrHeight)

Looks up a block header by hash or height in the current best chain.

Returns

Response::BlockHeader(block::Header).

Note: the HashOrHeight can be constructed from a block::Hash or block::Height using .into().

Transaction(Hash)

Looks up a transaction by hash in the current best chain.

Returns

• ReadResponse::Transaction(Some(Arc<Transaction>)) if the transaction is in the best chain;
• ReadResponse::Transaction(None) otherwise.

TransactionIdsForBlock(HashOrHeight)

Looks up the transaction IDs for a block, using a block hash or height.

Returns

• An ordered list of transaction hashes, or
• None if the block was not found.

Note: Each block has at least one transaction: the coinbase transaction.

Returned txids are in the order they appear in the block.

UnspentBestChainUtxo(OutPoint)

Looks up a UTXO identified by the given OutPoint, returning None immediately if it is unknown.

Checks verified blocks in the finalized chain and the best non-finalized chain.

AnyChainUtxo(OutPoint)

Looks up a UTXO identified by the given OutPoint, returning None immediately if it is unknown.

Checks verified blocks in the finalized chain and all non-finalized chains.

This request is purely informational, there is no guarantee that the UTXO remains unspent in the best chain.

BlockLocator

Computes a block locator object based on the current best chain.

Returns ReadResponse::BlockLocator with hashes starting from the best chain tip, and following the chain of previous hashes. The first hash is the best chain tip. The last hash is the tip of the finalized portion of the state. Block locators are not continuous - some intermediate hashes might be skipped.

If the state is empty, the block locator is also empty.

FindBlockHashes

Finds the first hash that’s in the peer’s known_blocks and the local best chain. Returns a list of hashes that follow that intersection, from the best chain.

If there is no matching hash in the best chain, starts from the genesis hash.

Stops the list of hashes after:

• adding the best tip,
• adding the stop hash to the list, if it is in the best chain, or
• adding MAX_FIND_BLOCK_HASHES_RESULTS hashes to the list.

Returns an empty list if the state is empty.

Returns

ReadResponse::BlockHashes(Vec<block::Hash>). See https://en.bitcoin.it/wiki/Protocol_documentation#getblocks

Fields

known_blocks: Vec<Hash>

Hashes of known blocks, ordered from highest height to lowest height.

stop: Option<Hash>

Optionally, the last block hash to request.

FindBlockHeaders

Finds the first hash that’s in the peer’s known_blocks and the local best chain. Returns a list of headers that follow that intersection, from the best chain.

If there is no matching hash in the best chain, starts from the genesis header.

Stops the list of headers after:

• adding the best tip,
• adding the header matching the stop hash to the list, if it is in the best chain, or
• adding MAX_FIND_BLOCK_HEADERS_RESULTS headers to the list.

Returns an empty list if the state is empty.

Returns

ReadResponse::BlockHeaders(Vec<block::Header>). See https://en.bitcoin.it/wiki/Protocol_documentation#getheaders

Fields

known_blocks: Vec<Hash>

Hashes of known blocks, ordered from highest height to lowest height.

stop: Option<Hash>

Optionally, the hash of the last header to request.

SaplingTree(HashOrHeight)

Looks up a Sapling note commitment tree either by a hash or height.

Returns

• ReadResponse::SaplingTree(Some(Arc<NoteCommitmentTree>)) if the corresponding block contains a Sapling note commitment tree.
• ReadResponse::SaplingTree(None) otherwise.

OrchardTree(HashOrHeight)

Looks up an Orchard note commitment tree either by a hash or height.

Returns

• ReadResponse::OrchardTree(Some(Arc<NoteCommitmentTree>)) if the corresponding block contains a Sapling note commitment tree.
• ReadResponse::OrchardTree(None) otherwise.

SaplingSubtrees

Returns a list of Sapling note commitment subtrees by their indexes, starting at start_index, and returning up to limit subtrees.

Returns

• ReadResponse::SaplingSubtree(BTreeMap<_, NoteCommitmentSubtreeData<_>>))
• An empty list if there is no subtree at start_index.

Fields

start_index: NoteCommitmentSubtreeIndex

The index of the first 2^16-leaf subtree to return.

limit: Option<NoteCommitmentSubtreeIndex>

The maximum number of subtree values to return.

OrchardSubtrees

Returns a list of Orchard note commitment subtrees by their indexes, starting at start_index, and returning up to limit subtrees.

Returns

• ReadResponse::OrchardSubtree(BTreeMap<_, NoteCommitmentSubtreeData<_>>))
• An empty list if there is no subtree at start_index.

Fields

start_index: NoteCommitmentSubtreeIndex

The index of the first 2^16-leaf subtree to return.

limit: Option<NoteCommitmentSubtreeIndex>

The maximum number of subtree values to return.

AddressBalance(HashSet<Address>)

Looks up the balance of a set of transparent addresses.

Returns an Amount with the total balance of the set of addresses.

TransactionIdsByAddresses

Looks up transaction hashes that were sent or received from addresses, in an inclusive blockchain height range.

Returns

• An ordered, unique map of transaction locations and hashes.
• An empty map if no transactions were found for the given arguments.

Returned txids are in the order they appear in blocks, which ensures that they are topologically sorted (i.e. parent txids will appear before child txids).

Fields

addresses: HashSet<Address>

The requested addresses.

height_range: RangeInclusive<Height>

The blocks to be queried for transactions.

UtxosByAddresses(HashSet<Address>)

Looks up utxos for the provided addresses.

Returns a type with found utxos and transaction information.

CheckBestChainTipNullifiersAndAnchors(UnminedTx)

Contextually validates anchors and nullifiers of a transaction on the best chain

Returns ReadResponse::ValidBestChainTipNullifiersAndAnchors.

BestChainNextMedianTimePast

Calculates the median-time-past for the next block on the best chain.

Returns ReadResponse::BestChainNextMedianTimePast when successful.

BestChainBlockHash(Height)

Looks up a block hash by height in the current best chain.

Returns

• ReadResponse::BlockHash(Some(hash)) if the block is in the best chain;
• ReadResponse::BlockHash(None) otherwise.

ChainInfo

Get state information from the best block chain.

Returns ReadResponse::ChainInfo(info) where info is a zebra-state::GetBlockTemplateChainInfo` structure containing best chain state information.

SolutionRate

Get the average solution rate in the best chain.

Returns ReadResponse::SolutionRate

Fields

num_blocks: usize

The number of blocks to calculate the average difficulty for.

height: Option<Height>

Optionally estimate the network solution rate at the time when this height was mined. Otherwise, estimate at the current tip height.

CheckBlockProposalValidity(SemanticallyVerifiedBlock)

Performs contextual validation of the given block, but does not commit it to the state.

It is the caller’s responsibility to perform semantic validation. (The caller does not need to check proof of work for block proposals.)

Returns ReadResponse::ValidBlockProposal when successful, or an error if the block fails contextual validation.

TipBlockSize

Returns ReadResponse::TipBlockSize(usize) with the current best chain tip block size in bytes.

Implementations

impl ReadRequest

fn variant_name(&self) -> &'static str

pub fn count_metric(&self)

Counts metric for ReadStateService call

Trait Implementations

impl Clone for ReadRequest

fn clone(&self) -> ReadRequest

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for ReadRequest

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

Formats the value using the given formatter.

impl PartialEq for ReadRequest

fn eq(&self, other: &ReadRequest) -> 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 Service<ReadRequest> for ReadStateService

type Response = ReadResponse

Responses given by the service.

type Error = Box<dyn Error + Sync + Send>

Errors produced by the service.

type Future = Pin<Box<dyn Future<Output = Result<<ReadStateService as Service<ReadRequest>>::Response, <ReadStateService as Service<ReadRequest>>::Error>> + Send>>

The future response value.

fn poll_ready(&mut self, _: &mut Context<'_>) -> Poll<Result<(), Self::Error>>

Returns Poll::Ready(Ok(())) when the service is able to process requests.

fn call(&mut self, req: ReadRequest) -> Self::Future

Process the request and return the response asynchronously.

impl TryFrom<Request> for ReadRequest

Conversion from read-write Requests to read-only ReadRequests.

Used to dispatch read requests concurrently from the StateService.

type Error = &'static str

The type returned in the event of a conversion error.

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

Performs the conversion.

impl Eq for ReadRequest

impl StructuralPartialEq for ReadRequest