Crate pallas_traverse

Expand description

A read-only, era-agnostic view over Cardano blocks and transactions.

Where pallas-primitives exposes the raw typed CBOR per era, this crate hides the era split behind MultiEra* enums so a single piece of indexing or analysis code can run against everything from Byron to Conway.

This is the read side of the ledger. For transaction construction see pallas-txbuilder; for ledger-rule validation see pallas-validate.

§Usage

use pallas_traverse::MultiEraBlock;

let block = MultiEraBlock::decode(&cbor_bytes)?;

println!("era={:?} slot={} hash={}", block.era(), block.slot(), block.hash());

for tx in block.txs() {
    for output in tx.outputs() {
        println!("  → {} lovelace", output.lovelace_amount());
    }
}

§Overview

MultiEraBlock, MultiEraTx, MultiEraHeader — top-level entry points with decode / decode_for_era constructors.
MultiEraInput, MultiEraOutput, MultiEraValue, MultiEraAsset, MultiEraPolicyAssets — per-piece views.
MultiEraCert, MultiEraRedeemer, MultiEraWithdrawals, MultiEraSigners, MultiEraMeta, MultiEraUpdate, MultiEraProposal, MultiEraGovAction — the rest of the tx surface, normalised across eras.
Era and Feature — discriminators for “which era is this” and “does this era support X” (multi-assets, smart contracts, CIP-1694, …).
Trait-driven hashing: ComputeHash and OriginalHash give a uniform way to take Blake2b digests of typed structures.
Per-aspect submodules for deeper helpers: block, tx, input, output, assets, value, cert, redeemers, witnesses, signers, hashes, fees, governance, time, header, meta, auxiliary, probe, size, withdrawals, wellknown.

§Feature flags

unstable — exposes APIs that are not yet considered stable and may change between minor releases.

§Usage as part of `pallas`

When depending on the umbrella pallas crate, this crate is re-exported as pallas::ledger::traverse.

Modules§

assets: Helpers for inspecting native and Plutus assets inside outputs and mints.
auxiliary: Helpers for transaction auxiliary data (metadata, native scripts, plutus scripts).
block: Block-level traversal: era detection, header access, transaction iteration.
cert: Helpers for inspecting on-chain certificates across eras.
era: Helpers for Cardano ledger eras and feature gating.
fees: Fee inspection and computation helpers.
governance: Helpers for Conway governance actions, votes, and proposals.
hashes: Stable hash computation for ledger entities (ComputeHash, OriginalHash).
header: Block-header traversal across era-specific header shapes.
input: Helpers for transaction inputs across eras.
meta: Helpers for transaction metadata.
output: Helpers for transaction outputs across eras.
probe: Era detection by probing CBOR shape. Lightweight inspection of block data without full CBOR decoding
redeemers: Helpers for Plutus redeemers.
signers: Helpers for required-signer hashes.
size: Size accounting helpers for transactions and blocks.
time: Slot / epoch / wall-clock conversion helpers.
tx: Transaction-level traversal: inputs, outputs, witnesses, etc.
update: Helpers for protocol-parameter update proposals.
value: Helpers for ada plus multi-asset values across eras.
wellknown: Well-known genesis hashes and parameter snapshots (will move to a genesis crate).
withdrawals: Helpers for reward-account withdrawals.
witnesses: Helpers for Plutus and native witnesses.

Structs§

OutputRef: Reference to a transaction output by transaction hash and output index.

Enums§

Era: The Cardano ledger eras in chronological order.
Error: Errors produced while traversing or decoding multi-era data.
Feature: Feature flags individual eras can be queried for.
MultiEraAsset: A single native or Plutus asset, normalized across eras.
MultiEraBlock: A block normalized across eras.
MultiEraCert: On-chain certificate normalized across eras.
MultiEraGovAction: Conway-era governance action carried by a MultiEraProposal.
MultiEraHeader: A block header normalized across eras, keeping access to its raw CBOR.
MultiEraInput: Transaction input normalized across eras.
MultiEraMeta: Transaction metadata normalized across eras.
MultiEraOutput: Transaction output normalized across eras.
MultiEraPolicyAssets: Multi-asset bundle for a single policy, normalized across eras.
MultiEraProposal: Conway-era governance proposal procedure.
MultiEraRedeemer: Plutus redeemer normalized across eras.
MultiEraSigners: Required-signer hashes normalized across eras.
MultiEraTx: A transaction normalized across eras.
MultiEraUpdate: Protocol-parameter update proposal normalized across eras.
MultiEraValue: Ada-plus-multi-asset value normalized across eras.
MultiEraWithdrawals: Reward-account withdrawals normalized across eras.

Traits§

ComputeHash: Recompute the hash of a value from its current in-memory shape.
OriginalHash: Recover the hash that the value had on the wire, preserving any encoding quirks.