estimateTrafficCost

estimateTrafficCost generates a commandId, forwards interactiveSubmissionPrepare with merged defaults (userId / actAs fall back to ledger client configuration), then delegates fee shaping to getEstimatedTrafficCost.

Requires userId (explicit or configured on LedgerJsonApiClient) and actAs parties.

Setup

import { Canton, estimateTrafficCost } from '@fairmint/canton-node-sdk';

const canton = new Canton({
  network: 'NETWORK_NAME',
  partyId: 'PARTY_ID',
});

Minimal example

const estimate = await estimateTrafficCost({
  ledgerClient: canton.ledger,
  commands: COMMAND_ARRAY_PLACEHOLDER,
  synchronizerId: 'SYNCHRONIZER_ID',
});

console.log(estimate?.totalCostWithOverhead, estimate?.costInDollars);

Parameters

EstimateTrafficCostOptions:

ledgerClient (required) — Supplies interactiveSubmissionPrepare.
commands (required) — Same CreateCommand / ExerciseCommand inputs as interactive submission.
synchronizerId (required) — Domain ID hosting the commands.
actAs, readAs, userId, disclosedContracts, packageIdSelectionPreference — Forwarded verbatim after defaults merge.

Returns

Promise<TrafficCostEstimate | undefined> — undefined when costEstimation absent from prepare response.

Errors

Throws Error when userId or actAs cannot be resolved.

Auth and party

Uses authenticated ledger credentials suitable for interactiveSubmissionPrepare.

Source

src/utils/traffic/estimate-traffic-cost.ts