buildPayload

Encodes a structured input object into a binary Uint8Array using the field layout from the ABI.

Signature

buildPayload(
  fields: BinaryField[],
  structs: Record<string, NamedStruct>,
  input: Record<string, unknown>,
  identityToPublicKey: (id: Identity) => Uint8Array,
): Uint8Array

Purpose

Encodes a structured input object into binary using the field layout from the ABI. The result is a Uint8Array ready to pass as inputPayload to transaction builders.

import { getAbi, getProcedure, buildPayload } from "@qubic.org/registry"
import { identityToPublicKey } from "@qubic.org/crypto"
import registry from "@qubic.org/registry/registry.json"
import type { ContractRegistry } from "@qubic.org/registry"

const reg = registry as ContractRegistry
const { version } = getAbi(reg, 9, 212) // Qearn at epoch 212
const proc = getProcedure(version, 6)   // lock_input

const payload = buildPayload(
  proc.inputFields,
  version.structs ?? {},
  { amount: 10_000_000n },
  identityToPublicKey,
)
// Returns Uint8Array — pass to wallet.buildScTransaction as inputPayload

Parameters

Name	Type	Description
`fields`	`BinaryField[]`	Field definitions from `procedure.inputFields` or `fn.inputFields`
`structs`	`Record<string, NamedStruct>`	Named structs from `version.structs`. Pass `{}` if unused.
`input`	`Record<string, unknown>`	Input object with keys matching the field names
`identityToPublicKey`	`(id: Identity) => Uint8Array`	From `@qubic.org/crypto`. Used to encode `id`-type fields.

Returns

Uint8Array — the binary-encoded payload.

Throws

PayloadBuildError — on type mismatch, missing required fields, or overflow.

identityToPublicKey and publicKeyToIdentity are passed as parameters rather than imported directly, keeping @qubic.org/registry tree-shakeable for server-side registry browsing that does not need the crypto library.