Listing mappers

The three functions that turn the listing backend’s wire JSON into the SDK’s shapes. getListingMarkets runs all of them for you, so you only reach for these when you hold a raw response yourself — a server route that proxies the backend, a fixture in a test, a cached payload you rehydrate.

import { toListingMarket, toListingMarketPage, toListingValue } from "@symmio/trading-core";

They are pure and synchronous. None of them takes a Config, touches the network, or raises a SymmError.

toListingValue

Parse one of the backend’s 18-decimal value strings into a bigint.

toListingValue("1000000000000000000"); // 1000000000000000000n  — 1.0 at LISTING_VALUE_DECIMALS
toListingValue("-25000000000000000"); // -25000000000000000n   — a negative APY
toListingValue(null); // null

Parameters

Returns

The return contract in full — three ways to get null, one to get a number:

Why the parse is lenient

The backend’s own schema types these fields as unsigned decimal strings. Live responses do not honor that on either count, so the parse handles both deviations rather than trusting the schema:

• Signs are preserved. The APY series carries negative values in practice, so a leading - survives into the bigint.
• Fractional tails are truncated toward zero. A fractional string would make BigInt() throw outright, so the digits after the decimal point are dropped rather than rounded: "1234.9" is 1234n and "-1234.9" is -1234n.

A string with no integer digits at all — ".5" — has nothing to truncate to and returns null, as does anything the pattern rejects ("n/a", "1e18").

toListingMarket

Map one raw row of the backend’s /v2/market/search response into a ListingMarket.

const market = toListingMarket(rawRow);

Parameters

Returns

What the mapping does:

• Renames the wire’s snake_case to the SDK’s camelCase (contract_address → contractAddress, open_interest → openInterest).
• Runs every money and rate string through toListingValue, so absent figures stay null.
• Folds the flat windowed columns into objects — apr_1h … apr_30d become aprByWindow.h1 … aprByWindow.d30, and the two APY series add the lifetime column they carry.
• Normalizes symbol_id and listing_time to null when the backend omits them.

chain_id and market_status are carried across as ListingDepositChainId and ListingMarketStatus. Both enums mirror the backend’s own values, so this is a naming of what arrived, not a validation of it — an unrecognized value from a newer backend passes through unchanged.

toListingMarketPage

Map the backend’s paginated envelope into a ListingMarketPage, mapping each row through toListingMarket on the way.

const page = toListingMarketPage(rawResponseBody);

Parameters

Returns

Every envelope field is defaulted rather than required because the generated schema marks them all optional — the backend declares defaults for them instead of demanding them.

Related

• getListingMarkets — the read that applies all three.
• ListingMarket — the shape they produce.
• Pools — the slice overview and the 18-decimal value contract.