Deriving keys and ids locally

Every id shield_swap_v3.aleo computes by hashing a struct is computable client-side, without the network. The helpers hash the exact preimage the contract hashes (BHP256 over the struct literal), so a locally derived value always matches the chain's. All of them load the optional @provablehq/sdk peer on first use; they are otherwise pure — no network, no signing.

The actions already fill these ids into their returns wherever the preimage is known — a local-signer swap or mint returns them from the transition outputs, and wallet-path actions derive them best-effort when the peer is installed. Reach for the helpers directly when reconstructing an id after the fact, or when addressing state you have not touched yet.

derivePoolKey

const poolKey = await derivePoolKey({ token0, token1, fee: 3000 })

BHP256(PoolKey { token0, token1, fee }), with the pair sorted ascending as the contract does — order-independent in the token arguments. The key every pool read and swap takes.

deriveTickKey

const tickKey = await deriveTickKey({ pool: poolKey, tick: -600 })

BHP256(TickKey { pool, tick }) — the ticks mapping key getTick reads.

deriveSwapId

const swapId = await deriveSwapId({
  poolKey, zeroForOne, amountIn, sqrtPriceLimit, blindedAddress, nonce,
})

BHP256(SwapKey) exactly as the swap transition computes it, with the blinded address occupying both the recipient and caller slots. The SwapHandle carries every preimage field, so a wallet-path id is computable from a persisted handle once the blinded address is known.

derivePositionTokenId

const positionTokenId = await derivePositionTokenId({ request, recipient, nonce })

BHP256(TokenIDPreimage { request, recipient, nonce }) exactly as mint computes it. Every preimage field is client-known before submission — including on the wallet path — so the id a mint will produce is computable ahead of confirmation.

deriveMultiHopSwapId

const swapId = await deriveMultiHopSwapId({
  tokenInId, tokenOutId, amountIn, amountOutMin,
  blindedAddress, hops, nonce, deadline,
})

BHP256(SwapMultiHopRequest) exactly as swap_multi_hop computes it — unused hop slots zero-padded, and, unlike the single-hop preimage, the deadline included.